# Bomber escort logistics?



## nincomp (Apr 19, 2013)

What were the logistics of fighter relays that escorted bombers?

First of all, when did allied bombers start getting fighter escorts in the ETO?

The first leg is easy, but it is the other legs that I wonder about. For example, did the fighters simply fly from airbases closer to the bombing target? Where were these airbases when the escorting missions started? 

In another thread, someone suggested the possibility of fighters escorting fighters. In this case, one set of fighters flew top-cover at "battle ready" speed, protecting the long-range fighters. The long-range might carry additional drop tanks, and/or fly at a relatively low cruise speed to conserve fuel for their leg of the bomber escort. 

I am open to the possibility that the real answer is obvious, and I just do not see it.

Thanks,


----------



## davebender (Apr 19, 2013)

If your fighter aircraft have adequate range and loiter time then you don't need as many. In any case you must have enough escort fighters with the bombers at all times to form a loose protective umbrella above them. Too few fighter escorts and they have no choice but to fly close escort.


----------



## tyrodtom (Apr 19, 2013)

No one group of fighters stayed with the bombers all the way to and from the target. 
One group might escort half way to the target, then they're replaced by another group. Which is then replaced by another, and so on.

You may have 1000 fighters escorting the bombers total, but only 200 fighters with them at any one time. That was why it was such a catastrophe if one of the scheduled rendevous of the escorting fighters were late, or navigated so far off they couldn't find the bombers.
And the fighters zig-zaged over the flight path of the bombers, that way they could stay at their higher cruise speed, and not outpace the bombers, but still be closer to their own combat speed.


----------



## nincomp (Apr 20, 2013)

tyrodtom said:


> No one group of fighters stayed with the bombers all the way to and from the target.
> One group might escort half way to the target, then they're replaced by another group. Which is then replaced by another, and so on.
> 
> You may have 1000 fighters escorting the bombers total, but only 200 fighters with them at any one time. -
> ...



Thanks,
I guess that I am still confused about where the later fighter relays were based in order for them to have enough fuel to stay with the bombers near the target.
Since the escorting fighters stayed at combat speed by performing S-turns above the bombers, they would, of course, burn more fuel than another group of similar fighters flying at their most economical cruise speed.

Did the second and later relays fly slower to the hand-off point in order to conserve fuel, or did they come from a base closer to the target?
If one set of fighters flew slower and/or had additional drop tanks, it would be logical for them to need the same kind of zig-zagging escorts as the bombers. It seems logical to me, but that does not mean that it actually happened, of course.


----------



## GregP (Apr 20, 2013)

This will be interesting and poke holes in the Hellcat in Europe naysayers. Yep, they cruised at economy settings and didn't fly over known flak locations or known figher opposition or heavily-defended targets at lower altitudes. It will work for numerous types, not just the ones who did it.

If you takeoff, climb to altitude at rather lazy rates, and cruise at lean economy settings, you can conserve a lot of fuel, which is why I think other types could also have done it. The types they used weren't much longer-ranged than proposed types in the "what if." The P-51 was a game changer because of its unrefueled range, but suffered from longitudinal instability when loaded past the aft CG limit (naturally!) as it was when all the starting fuel was aboard the aircraft including normal internal fuel, the fuselage tank, and the two drop tanks. Yes, the P-51 could DO it, but the plane wasn't exactly happy about it and would bite if mistreated, as will ANY aircraft past the aft CG limit.

They would takeoff on mains, switch to fuselage, burn that down until stablity returned, then switch to drop tanks until empty or attacked. Then jettison, fight ... and continue. If the Germans ever knew how unmaneuverable the P-51's were when full of fuel plus drop tanks, the main fighter opposition probably would have been as near to the P-51 airfield as they could get in order to attack when the P-51's were at a serious disadvantage. They never really knew and seemingly never tried for the same strategem themselves.

But their leadership was seemingly more interested in stealing priceless works of art in France than beating RAF Fighter Command ... maybe they just liked the food ...


----------



## Shortround6 (Apr 20, 2013)

nincomp said:


> Thanks,
> I guess that I am still confused about where the later fighter relays were based in order for them to have enough fuel to stay with the bombers near the target.
> Since the escorting fighters stayed at combat speed by performing S-turns above the bombers, they would, of course, burn more fuel than another group of similar fighters flying at their most economical cruise speed.
> 
> ...



Drgondog knows a lot more about this but I don't believe they ever bothered to use fighters to escort other fighters with large drop tanks. 

There seems to be lot of talk about "cruising speeds".







Please note that EVERY SPEED on this chart is a "Cruising speed". So you _could_ cruise an early P-47 at 300mph at 12,000ft burning 160 gallons an hour and fly 450 miles *OR* you fly at about 220-225mph ( there is a difference between true airspeed and indicated airspeed) at 12,000ft and burn 65 gallons an hour and fly 880 miles on the same fuel. Or pick speeds in between or at different altitudes. 

Second and later relays could fly slower up to a point, they also took off later. Escorts for the homeward legs might take-off a number of hours after the bombers and initial escorts took off.


----------



## davebender (Apr 20, 2013)

> as near to the P-51 airfield as they could get in order to attack when the P-51's were at a serious disadvantage.


P-51s didn't arrive until spring 1944 and P-51D didn't arrive until summer 1944. 

By summer 1944 1st and 2nd SS Panzer Korps were holding by their fingernails just south of Caen and Army Group Center was fighting for it's life (and losing) in Belarus. Under such circumstances sending intruder missions over England or English Channel was a low priority. Small scale intruder operations over England April to June 1944 came to a screeching halt after June 1944.

Perhaps things would have been different if P-51 bomber escorts had shown up a year sooner.


----------



## tomo pauk (Apr 20, 2013)

Locating LW fighters close to the P-51 bases would've been a major boon to the Allies. Here they can bring to the table Spitfires, Typhoons, Tempests, P-47s, along with decent number of the 2-engined bombers and wreak havoc with LW fighters. That would make the fighter opposition (vs. USAF) above Germany a non-issue, too.
The P-51B was a major player during the Big Week (February 20–25, 1944), the 73 P-51s taking part in it during the 1st day, only one lost in combat, claiming 37 LW planes. The initial operations in ETO were conducted in Dec 1943/Jan 1944. So it was still the winter when the P-51 made it's mark.


----------



## syscom3 (Apr 20, 2013)

davebender said:


> P-51s didn't arrive until spring 1944 and P-51D didn't arrive until summer 1944.



P51's began operations in Dec 1943 (in addition to a single P38 group). By the end of Feb 1944, there were four P51 groups and two P38 groups. By the end of March 1944, there were three P38 groups and five P51 groups.



> Perhaps things would have been different if P-51 bomber escorts had shown up a year sooner.



The same could be said about the P38's being operational in the summer of 1943.


----------



## tomo pauk (Apr 20, 2013)

I'd like to state that LW was ill able to do much about, in case the Allies introduced a 500 mile fighter during the summer of 1943. LW needed fighters to cover the preparation, execution and retreat from Battle of Kursk, while already being greatly outnumbered vs. Allies during the invasion of Sicily and, later Italy. The pressure in the ETO was growing every day, too, the absence of long-range fighter sweeps escorts giving the LW the much needed breathing space.


----------



## drgondog (Apr 20, 2013)

davebender said:


> P-51s didn't arrive until spring 1944 and P-51D didn't arrive until summer 1944.
> 
> *354th FG operational in ETO with Full compliment of P-51Bs in November 1943 and flew first combat mission under leadership of Lt,Col Blakeslee, the Gp Ops of 4th FG on December 1 to Knocke area.
> 
> ...



????


----------



## davebender (Apr 20, 2013)

RAF probably had more Mustangs then that operating over France and Norway. Not to mention hundreds of Spitfires participating in Circus raids on a regular basis. American P-51s would not get anyones attention until they starting showing up over places such as Berlin and Polesti.


----------



## drgondog (Apr 20, 2013)

GregP said:


> This will be interesting and poke holes in the Hellcat in Europe naysayers. Yep, they cruised at economy settings and didn't fly over known flak locations or known figher opposition or heavily-defended targets at lower altitudes. It will work for numerous types, not just the ones who did it.
> 
> *Between assembly and climb to altitude, the settings were fast cruise to R/V point..consistent with a.) extending total range, and b. Catching up to their assigned bomber wing somewhere in Germany for the deep Penetration/Target escort/Withdrawal leg. Essing with tanks was around 280mph TAS at 26,000+ while maintaining pace of 200mph TAS bombers until leaving escort or engaging in a fight.
> 
> ...



Maybe in the case you just cited, they weren't as smart as you and couldn't figure out how to beat RAF screen to catch P-51s in most vulnerable time (and correct place)?


----------



## Airframes (Apr 20, 2013)

RAF Mustangs at that time were the Mk1, Mk1A, and MkII - Allison engined, and used in Army Cooperation squadrons or Photo Recce, not as fighters or escorts.


----------



## drgondog (Apr 20, 2013)

nincomp said:


> Thanks,
> I guess that I am still confused about where the later fighter relays were based in order for them to have enough fuel to stay with the bombers near the target.
> 
> *All 8th and 9th AF Fighter Bases were north of London in East Anglia. Most P-47 bases were closer to Channel because of range limitations.*
> ...



Bombers didn't 'zig zag'. Nobody enjoyed keeping up in the turns and truly hated mid air collisions. The primary reason for Essing over the bombers was two fold. One to maximize coverage laterally over the bomber stream, and two to provide defensive cover. Escorts flew in two flight sections with one flight trailing and above the other to keep leader free of 6 o'clock bounce. One section crosses over toward the right side while the section crosses back to the left.

The bomber boxes of up to two BG's had a couple mile separation bewteen the leading box ahead, and the trailing box behind.

If a Mustang FG was covering 3 boxes over 15-20 miles, one Squadron would be out in front or high front of the leading box, one squadron would be in trail above the last box and one would be high center. Variations might include one squadron sweeping from front to back 5-10 miles off to one side, with one out in front and one high toward the rear box... and other variations


----------



## drgondog (Apr 20, 2013)

Airframes said:


> RAF Mustangs at that time were the Mk1, Mk1A, and MkII - Allison engined, and used in Army Cooperation squadrons or Photo Recce, not as fighters or escorts.



Terry - I have seen reference to RAF mark III's providing escort to some max effort 8th AF missions. IIRC none of the Mk III's prior to May 1944 had any internal fuselage tanks but I know that on April 24, 1944 Munich raid, some provided Withdrawal from Hildesheim back past Frankfort before being relived by P-47's


----------



## Airframes (Apr 20, 2013)

Yes Bill, you are correct. I was referring to the period between end of 1943 and March 1944. And yes, the fuselage tanks were a retro-fit, from around May '44 on, although some aircraft continued without them.


----------



## davebender (Apr 20, 2013)

Don't think that's the problem.

In the real world you don't get the benefit of hindsight with complete access to friendly and enemy historical records. Determining effectiveness of newly introduced enemy equipment and tactics is little more then guesswork. You don't even know effectiveness of your own newly introduced weapons for a few months. 

With the benefit of hindsight major nations such as Germany, Britain, France and USA would have nukes by 1939. They'd all be very polite to each other or else Europe (including Britain) gets blown off the map.


----------



## nincomp (Apr 20, 2013)

drgondog said:


> Bombers didn't 'zig zag'. Nobody enjoyed keeping up in the turns and truly hated mid air collisions. The primary reason for Essing over the bombers was two fold. One to maximize coverage laterally over the bomber stream, and two to provide defensive cover.



I did not mean to imply that bombers zigged or zagged. They were already going slower than the fighter cover.

It seems odd to me that even during the time when the range of the fighters was insufficient to escort the bombers all the way to the target, the fighters still burned up extra fuel to travel at a relatively fast cruise. 

I am more familiar with the P-38 than with the other fighters. The information that I have seen for the P-38 is that its maximum range was at about 185 MPH with the engines turning at 1600 RPM (at what altitude, I do not know). In this case, it would seem that to maximize escort distance, the fighters for the longer escort legs would lumber along at a low speed to save fuel until needed to climb and speed up to assume their escort duties. 
Of course the low and slow portion of the flight would need to be where there was little or no chance of being bounced by enemy fighters or being hit by flak. If enemy fighters could attack all the way along the planned route, it would make sense for the fighters to fly faster and at higher altitude.

I find it surprising that Mustangs would have their maximum range at such a high speed. At the moment, I can think of only a few reasons that this would be so: 
-The merlins unable to run well at low RPM
- the propeller is unable to operate at the required steep pitch
- some strange artifact of the mechanical superchargers 
- the wing is not efficient at the lower speed


----------



## Shortround6 (Apr 20, 2013)

It is not any of the first 3 and even the 4th isn't right. 

It isn't that P-51 _has_ it's maximum range at high speed. It doesn't. It is just that it is low enough in drag that it CAN cruise at those speeds AND cover the required distance with the available fuel. 

From Zeno's






Note the last column. 232mph at 5,000ft at 1600rpm and 28.5lbs manifold pressure while burning 42 gallons and hour. Close to the same speed and height as an Early P-47 and both can cover about 880 miles except the P-51 requires about 100 gallons less fuel. Or to put it another way the P-51 can fly 80-90 faster than the P-47 using the same amount of fuel per hour at 25,000ft and over 300mph. 

It can take plane several minutes to go from a low cruise (200mph or under) to top speed and if "bounced" at such a low speed it is at a very large disadvantage. It is at a very large disadvantage even with 15-20 seconds warning.


----------



## nincomp (Apr 21, 2013)

Shortround6 said:


> It is not any of the first 3 and even the 4th isn't right.
> 
> It isn't that P-51 _has_ it's maximum range at high speed. It doesn't. It is just that it is low enough in drag that it CAN cruise at those speeds AND cover the required distance with the available fuel.



Thanks for the info. This makes much more sense than my silly-assed theories.

To be honest, I was grabbing at straws because something had to be really bizzare with the P-51 if it was more efficient at higher speeds. The only thing that made sense to me was some very strange artifact from the engine or propeller.

I am new to this forum, so I do not know yet where to find the references to check on something that doesn't seem right to me. As you can tell, when something does not make sense to me, I am very good at coming up with half-baked theories.


----------



## GregP (Apr 21, 2013)

Well Drgondog, as unbelievable as it may sound, we have different opinions. But since you aren't willing to even try it, we wouldn't know unless I was commanding. Unlikely since I'm not old enough, and I would not care to continue the argument, if you can let it go. I can, and I still think it could be done, like some current Hellcat pilots do. I understand that you and other don't, but it won't be settled in here by words ... just with an aircraft flying the distance and profile that was required. 

I don't own one and that isn't likely, so we left with letting it go, OK?

Cheers. If you won't let it go, I decline to participate further in that argument, but understand quite well where you are coming from. It might well go either way but, if all you had were Hellcats, you might have to try.


----------



## barney (Apr 21, 2013)

It is my understanding that for long range missions and before escorting Mustangs, Spitfires would take the bombers across the channel, to be relieved by P-47's that were then relieved by P-38's. A second group of P-38's would be waiting for the bombers to come off target and into P-38 range to be then relieved by yet another group of P-47's and finally by Spitfires. So, with the murky weather over Europe it is easy to see how this could go wrong.

With Mustang escort a single group of Mustangs still didn't escort the bombers all the way to Berlin. The weaving patten they flew over bombers used too much fuel. Also, I think one of the reasons for the weaving was that the fighters had trouble flying at bomber speed at high altitude.


----------



## Shortround6 (Apr 21, 2013)

nincomp said:


> Thanks for the info. This makes much more sense than my silly-assed theories.
> 
> To be honest, I was grabbing at straws because something had to be really bizzare with the P-51 if it was more efficient at higher speeds. The only thing that made sense to me was some very strange artifact from the engine or propeller.
> 
> I am new to this forum, so I do not know yet where to find the references to check on something that doesn't seem right to me. As you can tell, when something does not make sense to me, I am very good at coming up with half-baked theories.



There are no dumb questions, only dumb answers. Stay and learn, sometimes a "half-baked theory" makes some of the "experts" here dig a little to find the right answer.


----------



## drgondog (Apr 21, 2013)

barney said:


> It is my understanding that for long range missions and before escorting Mustangs, Spitfires would take the bombers across the channel, to be relieved by P-47's that were then relieved by P-38's. A second group of P-38's would be waiting for the bombers to come off target and into P-38 range to be then relieved by yet another group of P-47's and finally by Spitfires. So, with the murky weather over Europe it is easy to see how this could go wrong.
> 
> *The 55th FG first flew combat in ETO on October 15, 1943. The second P-38 FG, the 20th FG first flew combat op on 28 December, 1943. The first P-51B FG, the 354th flew first combat op four weeks earlier. No more long range escorts until Feb 11 when second P-51FG, 357th, flew ops on Feb 11, 1944.
> 
> ...



The first belly tank mission and range to Holland/German border was July 28, 1943. The first P38 group (55th) would pick up the lead box of one bomb division near the German border and escort it to target and back to Holland area wher P-47s would provide Withdrawal.. because of the losses and subsequent rebuilding of crew strength the 8th didn't make penetrations deep into Germany - only a few as far as Brunswick and Halberstadt - until Big week.

Net - there was a span of six weeks in which the only long range fighter escort was P-38..in mid February there were two P-38 and two Mustang groups just in time for Big Week. All four could provide target support to Berlin but only the Mustang could go to Munich, for example.

Very little target coverage for 700 bombers over a 60-80 mile stream and always 'branching' to attack different targets.

Lot of gaps in target coverage and even gaps between Penetration support by P-47s, which then turn back near German border leaving the bombers alone until near the target when the P-38 or P-51 Group would pick up a box or two short of the target and return about 100-150miles if it was a deep target - then leave for home (no fuselage tank in Mustang until mid March 1944) leaving the bombers unprotected again until R/V with Withdrawal Support near German/Holland border.


----------



## drgondog (Apr 21, 2013)

GregP said:


> Well Drgondog, as unbelievable as it may sound, we have different opinions. But since you aren't willing to even try it, we wouldn't know unless I was commanding. Unlikely since I'm not old enough, and I would not care to continue the argument, if you can let it go. I can, and I still think it could be done, like some current Hellcat pilots do. I understand that you and other don't, but it won't be settled in here by words ... just with an aircraft flying the distance and profile that was required.
> 
> *Actually - it could be reasonably settled with a.) fuel consumption at 60% power while climbing to 26000 feet, then b.)fuel consumption for cruise power to achieve >250KTS at 26000 feet.
> 
> ...



Greg - Shortround nailed your 'beliefs' and assumptions to the barn door. I provided a mission profile which was standard ETO method for escorts and invited you to provide fuel consumption for the Hellcat to demonstrate that your assumptions for escort distances were reasonable.

Your only response seemed to be ad hominem flailing regarding our 'inability' to 'think out of the box'.

It is a simple math problem Greg and one every pilot knows by heart if planning a long IFR flight - which BTW is the Easiest of flight planning when compared to the escort problem.

So man up - dive into your references on R-2800-10W cruise speed fuel consumption with minimum 250KTS at 26000 feet. You can't use the Navy Flight Handbook simply because they didn't 'do' 26000 and probably would wonder why anybody would fly that profile in a Hellcat. Further, as it has been pointed out, the optimal cruise for the F6F was around 170kts for long range... at 12000 feet. You can't use that data or profile for this comparison against P-47 ops in ETO.

I would be delighted if you could just show near partity with P-47D prior to the -25.

As Tomo Pauk pointed out, you have a distinct tendency to shy away from solid sources for your imaginative assumptions.


----------



## nincomp (Apr 21, 2013)

Believe it or not, one of the reasons that I started this thread was to get info and avoid the F6F debate going on elsewhere on this site.
Oh well, another half-baked idea.


----------



## VBF-13 (Apr 21, 2013)

nincomp said:


> Believe it or not, one of the reasons that I started this thread was to get info and avoid the F6F debate going on elsewhere on this site.


I wouldn't have guessed.


----------



## Shortround6 (Apr 21, 2013)

nincomp said:


> Believe it or not, one of the reasons that I started this thread was to get info and avoid the F6F debate going on elsewhere on this site.
> Oh well, another half-baked idea.




Sometimes you do have sort the wheat from the chaff 

Drgondog is very knowledgeable about the 8th Air Force Missions. If he can't tell you how it was done (tactics, groups, spacing of flights) and when (dates tactics/procedures changed or specific missions) I am not sure who can. I would certainly not argue with him on those subjects.


----------



## Aozora (Apr 22, 2013)

Just for interest here's an interesting article comparing "Big Week" and the Battle of Britain:

View attachment Battle of Britain and Big Week Comparison.pdf




> During five days of attacks on German aircraft factories, the American Eighth Air Force flew 3,300 bomber and 2,548 fighter escort sorties, supplemented by 712 escort sorties by the Ninth Air Force. In the same period, the Fifteenth Air Force, based in Italy, flew just over 500 four-engine bomber sorties over Germany and 413 fighter escort sorties.10





> Before “Big Week,” Lt. Gen. James Doolittle, the Eighth Air Force’s commander, had informed his subordinates that the mission of the fighters was not to bring the bombers back safely, as had been official U. S. Army Air Forces doctrine since before Pearl Harbor, but simply to shoot down Germans.21 In a sense bombers served accompanying fighters as bait: and the more bait there was, the more the defending fighters exposed themselves to counter-attacks by fighter escorts. It also seems that the more bombers there were, the more frustrated, and eventually demoralized, the defending fighter pilots felt if the escorts made it impossible to get at them.22
> 
> 21. Lowell Thomas and Edward Jablonski, Bomber Commander: the Life of James Doolittle (London, 1977) p. 267. See also Richard G. Davis, Carl A. Spaatz: and the Air War in Europe (Washington, 1993) p. 359-60.
> 
> 22. See for example Heinz Knoke’s diary entry for 22 February 1944 in Heinz Knoke, I Flew For the Führer: the Story of a German Airman (London, 1953) p. 143.


----------



## syscom3 (Apr 23, 2013)

Interesting file you found there. Thanks!


----------



## Xjrtaz (Apr 25, 2013)

Here is a quote directly from my fathers memoirs which is in the process of being turned into a book for publication early next year, it explains the 56th's escort method from may 1944:
"the manner of providing the necessary cover for bombers was as follows:- The route of the bombers flight path was sectioned off into blocks. separate fighter groups covered the bombers through their particular block (approx. 45mins flight time for each block). Each fighter group knew from whom they were taking over and who was to take over from them. Only the group commander and his deputy had a channel to confer directly with the bomber commander in the air. each separate days cover meant a different sector from the last to provide escort, this meant that each group in turn had the opportunity to escort the bombers right to the target itself. in their particular sector the fighter escorts diverted the flak from the bombers where possible by flying a few seconds ahead, weaving to and fro (to avoid being hit) attracting the flak towards them enabling the bombers to take their straight course over the target as untroubled as possible.
I always looked forward to covering the last sector for it gave the opportunity to see the actual results of the bombing raid. The bombers were able to bomb through the clouds using the latest radar bomb site but this was dreary for us fighter pilots as the jerries would never attempt to intercept us in the air in bad weather and it was too dangerous and difficult for us to go hunting in such conditions.
The normal operational height of the bombers was around 24-25,000 feet so we flew between 27 - 32,000 feet. after providing our block of cover we were free (weather permitting) to either return to base or go hunting which most of the time we did..!"
As quoted by Witold `Lanny' Lanowski, I hope this helps as it is straight from the horses mouth (so to speak!!)
remember also , that the 56th had been experimenting with the `Zemke fan' from 1943 to fly ahead of the bomber stream to intercept the fighter as they rose to attack, this was done with the other squadrons not involved in the fan providing top cover against the main fan fighters being bounced.

I hope this helps and shed some light..

Krys


----------



## drgondog (Apr 25, 2013)

Un fortunately for the 56th, they were denied the opportunity to make the very deep penetrations so the only target busting the 56th saw was within 400 miles of Haleworth.

The 355th had a slightly different doctrine. The Gp leader and each of the other two squadron leaders had a crystal tuned to "C" channel - connected to the bombers, and depending on location in the escort stream, had the latitude to take his squadron to Help.

One other note. During the Briefing, the Division and Tail symbols for each Bomb Group that the fighters were assigned to were in order of position in that Division. Thus if the CO made R/V point and the first batch of bombers were identified as in the 'middle' but the fighters were assigned the Trailing boxes, then they would peel back along the stream until they found 'their' bombers.


----------



## Xjrtaz (Apr 25, 2013)

When the 56th moved to Boxted in 1944 from Halesworth and were subsequently given drop tanks, the range of the thunderbolt greatly increased giving them deeper range into Germany. Attached is a paper cutting from February 1945 when the 61st were over Berlin!!!


----------



## drgondog (Apr 25, 2013)

By that time Tempests and Jugs and Typhoons were deep into Germany. 

BTW, the 56th FG started flying with drop tanks late July 1943/early August 1943. They got P-47D-25's with 370 gallons of internal fuel and 2x150 gallons external fuel in August 1944 - and still couldn't get to Berlin until February 1945.

The 56th was flying the P-47M then and having serious problems with the engine electrical harness - with many aborts - which didn't get fixed until April, 1945.


----------



## OldSkeptic (May 1, 2013)

Basically as some have said here it was layered.

The composition of the layers changed over time. At the beginning the RAF did the short range protection (there and back). The P-47s and P-38s rendezvoused at different points and escorted to the limits of their range.
Later on the US had enough fighters to handle all the layers themselves (most of the time, sometimes they did call in the RAF).

As numbers built up the Mustangs took over more and more of all the layers (rather, than at first only the furthest ones) and the P-47s and P-38s moved to ground support.

The planning and logistics were complicated indeed, there could be 3 or 4 rendezvous points in a mission, sometimes more for very long range missions.

Price has some good examples in some of his books (forgot the ones right now but a google search will bring them up).

For a particular escort phase there usually was a group of fighters for top cover, to prevent bounces, a forward cover sweeping ahead and others pacing the bomber formation (at a distance). The idea being that they could intercept whatever direction the Germans came from.

At the beginning fighter cover tended to be too close, as time went on and hard experience taught lessons, it was loosened. Naturally the further away from the bombers the fighters engage the better.


----------



## stug3 (May 3, 2013)

May,3 1943 No. 487 Squadron RNZAF wiped out in daylight raid on Dutch power station

London Gazette March 1, 1946-

In 1943 daylight bombing raids on Germany and occupied Europe were mostly left to the USAAF. However the RAF mounted smaller attacks using their medium aircraft. The Mosquito was well suited to this role, given its speed. Less suitable were Ventura aircraft, which were heavily dependent on a fighter escort to give them protection. They did not last long in RAF frontline service and this raid was one of the reasons why. 

On the 3rd May, 1943, Squadron Leader Trent No. 487 Squadron RNZAF, was detailed to lead a formation of Ventura aircraft in a daylight attack on the power station at Amsterdam.

This operation was intended to encourage the Dutch workmen in their resistance to enemy pressure. The target was known to be heavily defended. The importance of bombing it, regardless of enemy fighters or anti-aircraft fire, was strongly impressed on-the air crews taking part in the operation.

Before taking off, Squadron Leader Trent told the deputy leader that he was going over the target, whatever ‘happened.

2. All went well until the Venturas and their fighter escort were nearing the Dutch coast. Then one bomber was hit and had to turn back. Suddenly large numbers of enemy fighters appeared. Our escorting fighters were hotly engaged and lost touch with the bombing force. The Venturas closed up for mutual protection and commenced their run up to the target. Unfortunately, the fighters detailed to support them over the target had reached the area too early and had been recalled.

3. Soon the bombers were attacked. They were at the mercy of 15 to 20 Messerschmitts which dived on them incessantly. Within four minutes six Venturas were destroyed. Squadron Leader Trent continued on his course with the 3 remaining aircraft.

4. In a short time 2 more Venturas went down in flames. Heedless of the murderous attacks and of the heavy anti-aircraft fire which was now encountered, Squadron Leader Trent completed an accurate bombing run and even shot down a Messerschmitt at point-blank range. Dropping his bombs in the target area, he turned away.

The aircraft following him was shot down on reaching the target. Immediately afterwards his own aircraft was hit, went into a spin and broke up. Squadron Leader Trent and his navigator were thrown clear and became prisoners of war. The other two members of the crew perished.


No. 487 Squadron RNZAF grouped in front of a Lockheed Ventura Mark II at Methwold, Norfolk






Armourers load 250-lb GP bombs into a Lockheed Ventura Mark II of No. 487 Squadron RNZAF at Methwold, Norfolk


----------



## stug3 (Sep 27, 2013)

From Heinz Knoke: I flew for the Fuhrer: Story of a German Airman

_Heinz Knoke was already an accomplished Luftwaffe pilot by 1943, well on his way to his final tally of 52 aircraft. He and his flight had mastered the right approach to taking on the B-17s. Today, however, there was a surprise:

27th September, 1943.

Enemy concentrations in map reference sector Dora-Dora. Once again the time has come. . . . 1030 hours: stand by. 1045 hours : all set.

I have a new aircraft. Arndt has been polishing it until it shines like a new mirror: no doubt that will add another ten miles per hour to the speed.

1055 hours: the call to action blares as usual from the loudspeakers round the field: “ All Flights take off! All Flights take off! ”

The sky is completely overcast. We come out above the clouds at 10,000 feet, and at the same moment sight our Fortresses directly overhead. We climb on a parallel course, heading east up to 20,000 feet. That is as high as they are flying today.

The reserve tanks are still almost full when I order my Flight to jettison them. We swing quickly in to attack with our rockets. As we get into position, the Fortresses split up into separate groups of some thirty or forty aircraft each, and keep on constantly altering course. The moisture-trails above the cloudbank leave a zigzag pattern in the blue sky.

I order all our rockets to be discharged when we are in formation at a range of 2,000 feet. The next moment a simply fantastic scene unfolds before my eyes. My own two rockets both register a perfect bull’s-eye on a Fortress. Thereupon I am confronted with an enormous solid ball of fire. The bomber has blown up in mid-air with its entire load of bombs. The blazing, smoking fragments come fluttering down.

Wenneckers also scores a direct hit. His victim goes down in flames. My wingman, Sergeant Reinhard, has discharged his rockets to explode beside another Fortress.

The fuselage appears to be damaged, too, and it swerves away off to the left. I observe how Reinhard chases off merrily after it, blazing away with his guns. He fastens on to the tail of the American.

My attention just then is attracted by the rather peculiar appearance overhead of double moisture trails, apparently emanating from very fast aircraft.

Messerschmitts and Focke-Wulfs, as far as I know, have been sent into action from our side. The peculiar-looking planes keep circling above the bombers. If they are German why do they not attack? I climb up alone for a closer look at them. Lightnings! Twelve or fourteen aircraft: the Yank has brought a fighter escort. I radio the warning to my comrades. Since I cannot undertake operations against them by myself alone, I decide to swoop down once more upon the Fortresses.

Then suddenly four other peculiar-looking single-engine aircraft dive past. They have the white star and broad white stripes as wing markings. Blast! They are Thunderbolts. I have not seen them before.

I immediately dive down after them. They swing round in a steep spiral to the left, heading for a lone Flying Fortress whose two outside engines have stopped. There is a Messerschmitt on its tail: it is Reinhard. The bloody fool has eyes only for his fat bomber, and is unaware of the enemy fighters coming up behind. keeps on firing at his victim.

But now the leading Thunderbolt is a perfect target in my sights. A single burst of fire from my guns is all that is needed. It bursts into flames and goes down spinning like a dead leaf into the depths below. It is my second kill today.

Then there is a sudden hammering noise in my crate. I turn round. There is a Thunderbolt hard on my tail, and two others are coming down to join it. I push the stick right forward with both hands, diving for cover in the clouds.

Too late: my engine is on fire. I can feel the heat: it quickly becomes unbearable.

Knoke survived by parachuting out and was uninjured. Many of the fellow pilots in his Squadron were less fortunate. In one flight of twelve aircraft nine pilots were killed and the three other planes crashed or the pilot had to bale out._


Knoke was flying the Messerschmitt Me 109 G or ‘Gustav’. Seen here in 1944 equipped with cannon. 






Luftwaffe ground-crew (“black men”) positioning a Bf 109 G-6 “Kanonenvogel” equipped with the Rüstsatz VI underwing gondola cannon kit. Note the slats on the leading edge of the port wing. JG 2, France, autumn of 1943.






P-38F-1-LO over California during factory test flights (U.S. Air Force)






The Republic P-47 Thunderbolt which was now reaching the USAAF in England in numbers.


----------



## drgondog (Sep 27, 2013)

davebender said:


> P-51s didn't arrive until spring 1944 and P-51D didn't arrive until summer 1944.
> 
> *Dave - you have been corrected on this numerous times and references have been provided. In the ETO, discounting the RAF Mustang I and II, the first Combat operations for the P-51B was December 1, 1943. By March 21 (spring), 1944 there were four more P-51B groups operational. Total = 354, 357, 363, 4 and 355 before March 8, 1944. The 352nd was in transition before 'Spring 1944'. The P-51A and A-36 were flying combat Ops in April through June 1943. A-36 and P-51A in CBI in July 1943.
> 
> ...



P-51A's were flying relatively long range escort to MTO bombers in July, 1943 - combined with the P-38 - but only escorting medium bombers at medium altitudes. Essentially the same range as the P-51B-1 and P-51B-5 before the fuselage tank additions.


----------



## GregP (Sep 28, 2013)

Just got back to this after a long time and noticed Bill's post #26. You sure drip friendliness when you're on, Bill. On the surface, you're a typical nay-sayer. It was already obvious that the standard profile wasn't going to work. How many other profiles did you try to see if it could be done before you started the sarcasm? None?

Maybe you wouldn't have planned the Yamamoto mission either since it was "out of normal range?"

The Hellcats wouldn't have to cruise at 250 knots and they don't have to match your profile or any profile. My "what if" was to find a profile to make it work because that's all you had to do it with at the time ... and you still don't seem to get that part. We already know it wasn't the case, but that's the way it is with all "what ifs," not just this one.

The challenge is to find a profile by which the F6F could provide escort there and back. If you can't, then you can't. Obviously you and Shortround can't think of a way to make it work, so we'll just say you both decline the mission and we proceed on that basis.

The bombers are on their own. All those Hellcats and nobody can figure out a way to make them useful. Seems like waste of Hellcats to me. Ah well, war is hell.


----------



## OldSkeptic (Sep 28, 2013)

I missed that one Greg. Why would you put a plane with roughly the performance of a Spit V on an escort mission in '44? 
Whether or not it had the range is irrelevant, it just didn't have the performance to live in that environment at that time.

I'm all for 'thought experiments' and all that (do them myself), but that one seems a bit silly to me.


----------



## Shortround6 (Sep 28, 2013)

GregP said:


> The challenge is to find a profile by which the F6F could provide escort there and back. If you can't, then you can't. Obviously you and Shortround can't think of a way to make it work, so we'll just say you both decline the mission and we proceed on that basis.
> 
> Ah well, war is hell.



Why don't you _show_ us the flight profile then??

You keep saying we are wrong or can't think out side the box or some other flip phrase/put down. 

Come up with a valid flight plane profile. And cruising at 180mph at 5,000ft _TO_ a rendezvous point over land with patches of 37mm AA guns is not a good plan. 

What is the fuel burn of the F6F at the Altitudes and speeds _needed_ to do the B-17/B-24 escort mission in Europe?

Or are you going to cast insults/aspersions at us and then hide behind "lets agree to disagree" when we ask you for facts.


----------



## nuuumannn (Sep 28, 2013)

Very interesting discussion, just as an aside, StuG3, good info about Trent and 487 Sqn, but a little correction; 487 was not an RNZAF unit, it was a New Zealand unit of the RAF - there is a difference. the Kiwi Article XV squadrons in the 400 series were on the order of battle of the RAF, not RNZAF.


----------



## stug3 (Sep 28, 2013)

Then why is it always identified as RNZAF? It was an RNZAF unit under operational command of the RAF.


----------



## drgondog (Sep 28, 2013)

GregP said:


> Just got back to this after a long time and noticed Bill's post #26. You sure drip friendliness when you're on, Bill. On the surface, you're a typical nay-sayer. It was already obvious that the standard profile wasn't going to work. How many other profiles did you try to see if it could be done before you started the sarcasm? None?
> 
> *Ah, Greg are your feelers hurt because I pointed out the obvious and in another thread dealt you the mission parameters that an F6F would have to fly to hang with B-17s in escort role. It is you that avoids putting your brain to work and demonstrate that either Shortround or I misjudged the parameters. If you think the post wasn't 'friendly' or oozed sarcasm I have reposted below for you to revisit.
> 
> ...



*To revisit what I said in post 26*
_Greg - Shortround nailed your 'beliefs' and assumptions to the barn door. I provided a mission profile which was standard ETO method for escorts and invited you to provide fuel consumption for the Hellcat to demonstrate that your assumptions for escort distances were reasonable.

Your only response seemed to be ad hominem flailing regarding our 'inability' to 'think out of the box'.

It is a simple math problem Greg and one every pilot knows by heart if planning a long IFR flight - which BTW is the Easiest of flight planning when compared to the escort problem.

So man up - dive into your references on R-2800-10W cruise speed fuel consumption with minimum 250KTS at 26000 feet. You can't use the Navy Flight Handbook simply because they didn't 'do' 26000 and probably would wonder why anybody would fly that profile in a Hellcat. Further, as it has been pointed out, the optimal cruise for the F6F was around 170kts for long range... at 12000 feet. You can't use that data or profile for this comparison against P-47 ops in ETO.

I would be delighted if you could just show near partity with P-47D prior to the -25.

As Tomo Pauk pointed out, you have a distinct tendency to shy away from solid sources for your imaginative assumptions._


----------



## nuuumannn (Sep 28, 2013)

> Then why is it always identified as RNZAF?



Because those who do identify it as RNZAF unit don't understand the relationship between the RNZAF and the Article XV squadrons.

This from the RNZAF's own website:

"Many New Zealanders served in the seven "New Zealand" RAF Squadrons Nos. 485– 490, established under Article XV of the BCATP Agreement, to ensure a continued linkage of airmen with the nations that formed the British Commonwealth."

This is slightly incorrect; there were only six.

RNZAF - RNZAF in World War II



> It was an RNZAF unit under operational command of the RAF.



No, it was not. It was an RAF unit. 487 was one of the Article XV squadrons of the British Commonwealth Air training Plan.

This from the Wiki entry on 487 Sqn, which is incorrectly titled 'RNZAF':

"Administratively the "Article XV squadrons" were an integral part of the RAF, with all command appointments being made by the RAF."

...and:

"There is some debate about the naming conventions of the New Zealand Article XV Squadrons. Some authors such as Bill Gunston have used designations like "485 Squadron RNZAF", because that is how it is presented on their unit crests, but others believe that this is misleading as *the Article XV Squadrons were part of the RAF*. Gerard Morris has stated that the anomaly "...carried over into the naming of the six New Zealand squadrons...It was impractical, for operational and administrative reasons to establish and maintain RNZAF squadrons in Britain. So, although the squadron badges carried the name Royal New Zealand Air Force, the squadrons were in fact receiving their pay cheques from the British government and official records such as the Operations Record Book acknowledged this. For example, 485 Squadron was referred to informally as 485 (New Zealand) or 485 (NZ) and *never as "485 Squadron, RNZAF"*."

https://en.wikipedia.org/wiki/No._487_Squadron_RNZAF


----------



## syscom3 (Sep 28, 2013)

The Hellcat would have been a failure as a high altitude bomber escort. It was designed for naval aviation mission profiles and nothing else. It was good at what it was built for, so leave it at that.


----------



## drgondog (Sep 28, 2013)

Syscom - by definition any idea or concept that Greg is passionate about is a 'good idea'. It is dolts like you, Shortround and me that can't see it because we can't think out of the box..

I suppose Greg will finally decide that 8th AF had it all wrong and needed to focus on 12,000 altitude, 150mph TAS, to adapt to the F6F best cruise specs. Having said that, the first mission is likely to encounter a large force of very good aircraft with a 200+ mph speed and altitude advantage, and if the remaining F6F's goes all the way to Berlin, none of them come back. Surviving naval aviators captured somewhere between Dummer Lake and Osnabruck.

Problem solved. Next up, F4F.


----------



## Aozora (Sep 28, 2013)

stug3 said:


> Then why is it always identified as RNZAF? It was an RNZAF unit under operational command of the RAF.



Ditto nuuuumann - the true RNZAF squadrons were either based in NZ or the Pacific: RNZAF - RNZAF in World War II the distinctions between the two can be hazy to "foreigners" and even to many New Zealanders, but it is very clear - the article XV squadrons were RAF units with New Zealand personnel: same applies to Australian 450 - 460 series squadrons in the RAF (so 450(Aust) Sqn.) and Canadian 400 - 430-440 series squadrons.

The Article XV RAF units were:

400 to 443(Canadian) Squadrons;
460 to 467(Aust) Squadrons;
485 to 490(NZ) Squadrons.


----------



## nuuumannn (Sep 28, 2013)

The Aussies and Canadians had different identities and maintained their own loyalties far stronger than the Kiwi Article XV squadrons; the Canadian Article XV squadrons were units of the RCAF under RAF control; indeed, the Canucks had their own Group in Bomber Command, but the Aussies and Kiwis did not. 

https://en.wikipedia.org/wiki/Article_XV_squadrons

Some of the Aussie units were also formed in Australia and were also RAAF squadrons under British jurisdiction, like the Canadian units, but the New Zealand units were distinctly RAF units and all, with the exception of 488 and 490 - in Jui North West Africa, were formed in the UK. 488 Sqn, although formed in Wellington recived its aircraft in Singapore, RAF Brewster Buffaloes; the RNZAF never operated the type. Once Singapore fell, the remaining squadron personnel returned to New Zealand and requested that the squadron be reactivated, but the British stated that 488 was an RAF unit and that number could not be used. 488 was reformed on Beaufighters in the UK in 1942.


----------



## nuuumannn (Sep 28, 2013)

JHust to add fuel to the fire and to ask the question, which seems to have eluded some people, why _would_ you use a aircraft carrier based naval interceptor to carry out long range escort of bombers over Europe, when there were far better suited aircraft with better performance in theatre to do that job? Its like stating that the Avro Anson made a good fighter because one shot down two Bf 109s and damaged a third (I've used this example before, but it's entirely fitting, I think).

It has been demonstrated in people's mind that it was certainly possible and that it _could_ be done, but the question has to be asked, why _would_ you?


----------



## GrauGeist (Sep 28, 2013)

As far as Hellcats and such goes in the ETO...

If the Allies thought that a certain type of aircraft would be superior for bomber escort/protection, they would most certainly use it and not waste time/lives/assets experimenting.

As it turns out, they found the correct aircraft and used those aircraft to the fullest of extent of thier capabilities.

Obviously, the Hellcat wasn't one of them...


----------



## mhuxt (Sep 29, 2013)

This also gets back to the scans of RAF strength Neil posted recently, and why some Mossies and Spits (among others?) appear unaccounted for in Australia. There were Mosquitos in the Far East under direct RAAF control (for example No. 1 Attack Squadron), which were in a chain of command quite distinct from RAF control over squadrons like 456 and 464.


----------



## GregP (Sep 29, 2013)

Drgondog and Shortround, first, here is a,link: http://www.history.navy.mil/branches/hist-ac/f6f-5.pdf

I see Drgondog is as polite as ever above, so here goes:

Berlin is 580 air miles from London. So, round trip is twice that or 1,160 miles.

Attached above is a document about the F6F Hellcat. It is accurate. According to the document, the F6F-3 and -5 have clean ranges of 1,090 and 1,130 miles respectively. So, with NO reserve the Hellcat falls 30 miles short. With a 160 gallon centerline tank, the range goes to 1,590 miles and 1,650 miles respectively. That covers it all by itself with combat range, no problem.

However, note later in the document that the combat range with a single 150 gallon centerline fuel tank is 950 nautical miles or 1,093 statute miles. So it is really VERY simple. Launch with two or more external tanks and you have the range as long as you can get 200 -300 miles in before dropping one of them. At ANY point in the mission, you can drop tanks are return even with combat allowances and fight most of the way back. 

To preclude the possibility of failure, launch with more Hellcats than you need and if they have to drop all tanks before 200 – 300 miles, then THEY fight the first attack wave and return home. The rest follow behind and continue the escort at best range cruise speed. I guarantee the B-17’s would rather cruise at the Hellcat’s best cruise speed than do without escort. If they don’t want to do that, order them to do it. Simple, effective, and possible.

If they upped the manifold pressure a bit and dropped the RPM like Lindberg did with the P-38’s in the Pacific, I bet they could do it without the second tank.

You guys are so negative and so opposite can-do that it is comical. It just isn't that tough.

Of course, we didn't deploy Hellcats to the ETO in any numbers (that happens in a what-if), but it COULD have been made to work if there were no alternatives. 

Since we can't seem to have a polite "what if" or, indeed, polite almost anything, I won't ask you to engage further in what ifs. That's a shame since we could have some fun if only you could find a way to be civil.

For some reason, you just don't want to play nicely in the sandbox. If you get around Chino, drop in and we can be nasty face to face while we tour the museum. Maybe share a beer afterwards.

Cheers.


----------



## OldSkeptic (Sep 29, 2013)

GregP said:


> Drgondog and Shortround, first, here is a,link: http://www.history.navy.mil/branches/hist-ac/f6f-5.pdf
> 
> I see Drgondog is as polite as ever above, so here goes.....



Precisely. What a lot of people don't get is that the *combat* range depends on how much fuel is left after external tanks are dropped (and CoG affecting rear tanks emptied) *and *you have combat and an escape. Fairly reasonable to assume you return basically unaffected (if you want) at a high altitude at most economical cruise.
For shorter missions, and you haven't shot off all your ammo, then you can shoot up things on the way home too.

In my LR Spit calcs I assumed 15 mins combat at max power, then economical cruise for return home after that and got to Berlin easily with a rear tank (plus a reserve). The same is for true any other plane.

The Mustang was no different, except in that, even with the rear tank empty it had a lot of fuel and an efficient engine (plus low drag of course), hence it was really a VLR fighter (if you define LR as Berlin and onwards as VLR). 

As for that 15 mins, that is a lot of combat time at full power. Even in combat full power (and maximum consumption) was used only sparingly. Thus the actual combat time could have been longer, with much of it at more reduced power settings. Basically you would have ran out of ammo fairly quickly as well.


----------



## bob44 (Sep 29, 2013)

GregP said:


> Drgondog and Shortround, first, here is a,link: http://www.history.navy.mil/branches/hist-ac/f6f-5.pdf
> 
> I see Drgondog is as polite as ever above, so here goes:
> 
> ...



In that report, it states the combat radius as 340nm with 150g drop tank, and combat range of 950nm. Both at a 15000ft altitude.


----------



## Rufus123 (Sep 29, 2013)

This is off topic but I am curious. 

The talk of the Hellcats being used in Europe has made me wonder.

If the war for some reason ended in the Pacific quickly do to pure brilliance on the part of the allies and incompetence of Japan or I guess the Japanese see the writing on the wall and come to terms. What happens to all this naval airpower?

You have the pilots and planes. Do you have more carriers than are needed for Europe with the Pacific war complete? Do some of the Naval assets become land based? Clearly from what I have read they are not going to do the long range escort but there might be plenty of jobs they could do?


----------



## OldSkeptic (Sep 29, 2013)

Now this is going to piss some people off, but realistically none of the US carrier planes were competitive in the European theatre on a *like by like* basis. 
Translated it is no use comparing a Bearcat vs a '42 109, because they were years apart.

Therefore it would be a Hellcat vs a late 43/44 109 or 190 ... they would be slaughtered. A Hellcat had basically the same performance as a Spit V .. and it was obsolescent in 42...

So, apart from some CAS stuff, which the Allies had heaps of anyway with the Typhoon, -47 and so on what could they do?

By their very nature carrier planes have lower performance than land ones. They have to be heavier (arrester equip, stronger construction for the landings and so on) therefore they will be slower.
They have a requirement for a slow landing speed, which means a low wing loading and hence (unless you are really clever, like for the Spitfire) draggier.

The combination of all those (and this applies even now) means lower performance. You go for sheer performance and then you get the issue with the early Seafires (the later ones were far better), too delicate.

Take an example from the time (it is a good one because there were direct comparisons), the DH Hornet vs the DH Sea Hornet. Same plane, same engines, but configured for carriers it was 20mph slower and lot heavier. (hence lower climb rate as well). A land Hornet version would have ran rings around a Sea Hornet version.

So they would have effectively, except for some niche operations, useless.


----------



## Rufus123 (Sep 29, 2013)

OldSkeptic said:


> Now this is going to piss some people off, but realistically none of the US carrier planes were competitive in the European theatre on a *like by like* basis.
> Translated it is no use comparing a Bearcat vs a '42 109, because they were years apart.
> 
> Therefore it would be a Hellcat vs a late 43/44 109 or 190 ... they would be slaughtered. A Hellcat had basically the same performance as a Spit V .. and it was obsolescent in 42...
> ...



I was guessing that the naval planes would be given a ground attack role. 

Is it remotely possible (inter service problem maybe) that many of these trained naval aviators would get a transfer to the Air Corps and be put into land based aircraft? Seems like a faster way to get the trained pilot body count up in Europe. Maybe able to slow down recruiting and training new pilots as there could be a surge in new aviators.


----------



## drgondog (Sep 29, 2013)

GregP said:


> Drgondog and Shortround, first, here is a,link: http://www.history.navy.mil/branches/hist-ac/f6f-5.pdf
> 
> I see Drgondog is as polite as ever above, so here goes:
> 
> ...



Greg - your scholarship and analytical approach to this question is pedantic. You find the standard USN data on the Internet which does not include really important data for the following:
1. Fuel consumption for boost and rpm for different cruise speeds at different altitudes.
2. Fuel consumption for Take off, orbit for formation assembly and climb to 25000 feet
3. Fuel consumption for WEP and MP at any altitude.
4. Cruise speeds for clean and for external stores as a function of altitude 

You are pedantic at pointing to tabular range radius tables which do not reflect real life for US bomber escort in the ETO.

Here is food for thought. The Brits did a combat range calc for 20,000 feet but didn't state the speeds... suspect the speed is around 244mph which is quoted as 'best/most economical" cruise speed to get 420 miles.
http://www.wwiiaircraftperformance.org/f6f/hellcat-II-ads-b.jpg 


If you have the energy to at least look at one set of CALCULATED comparisons using .5gallons/HP for cruise, Oswald factor=.85, propeller efficiency = .8 - INTERNAL Fuel only for all a/c compared. The data also assume no take off or climb, no combat, and uses best cruise speeds at best altitudes. These calcs also assume start at altitude, mid air refuel to top off tanks and fly until you drop out of the sky..using Brequet equations to calc weight loss due to fuel consumption. 

From Tables 98 and 99, page 598 America's Hundred Thousand 

A/C -------Fuel (Gallons)----Range miles (NOT Radius)
P-47D-25 370 ----------------1135
P-47D-5 305-----------------1020
P-51D-10 269-----------------1443
F6F-5---- 250-------------------849

Note: The P-47D-5 had the R-2800-21,with same SFC, at same throttle/rpm as the F6F-5 R-2800-18

BTW - the P-47D-25 had approximately 7% better max L/D and 7% less profile drag than the F6F-5 and it Could Not be assigned to escort to Berlin with 26% more internal fuel than the F6F-5

As a side note go look up the P-47D-1 through -23 which had 55 gallons more internal fuel, cruised efficiently at faster speeds at any altitude and operated efficiently at 30,000 feet. The tables in America's Hundred Thousand, for example, place the P-47D-25 with 370 gallons internal and 300 external at 670 mile combat radius (with no altitude or cruise speed stated) and yet no P-47s went to Berlin until February 1945 with the P47M. 

A last note - from the same reference. Where Combat Radius tables are prepared with the assumptions for takeoff, climb, best cruise to target, combat, return at best cruise have a 30 minute reserve, the P-47 and P-51 both had 7% better radius at 10,000 feet than at 25,000 feet.


The specific fuel consumptions for the R-2800's used in the P-47 and F6F were the same

The P-47D-25 with 370 gallons internal and no external tank had a combat radius of 225 miles in the same table.

Once again Greg - trot out real data relevant to ETO conditions and show us what ya got.


----------



## drgondog (Sep 29, 2013)

http://www.wwiiaircraftperformance.org/p-47/p-47-differences.jpg

Note - the P-47D-30 which never went to Berlin has a tactical combat radius of 600 miles with 370 gallons internal fuel, 330 gallons external fuel. The P-47D-5 could go 225miles combat radius with 305 gallons internal fuel

Greg - one more time. 

Why do you think the Hellcat with just over half the fuel with standard 150 gallons external fuel (410gallons) can go to Berlin and back with reasonable expectation of getting them back to England? Even at best cruise conditions of 12,000 feet and 200 mph?

Repeat - assuming you carried 3000 gallons of external fuel (a joke), made it to East Berlin with all 250 gallons of internal fuel remaining, fought for 20 minutes at 360+ gallons per hour to reduce your internal fuel to 160 gallons and had to return in a straight line with no reserve the 580 miles back. 

Good luck when you consider a P-47D-30 can't do it when it starts with 370 internal, loses 90 gallons in the same scenario down to 280 gallons - or 75% more than your F6F-5


----------



## Shortround6 (Sep 29, 2013)

OldSkeptic said:


> Precisely. What a lot of people don't get is that the *combat* range depends on how much fuel is left after external tanks are dropped (and CoG affecting rear tanks emptied) *and *you have combat and an escape. Fairly reasonable to assume you return basically unaffected (if you want) at a high altitude at most economical cruise.
> For shorter missions, and you haven't shot off all your ammo, then you can shoot up things on the way home too.
> 
> In my LR Spit calcs I assumed 15 mins combat at max power, then economical cruise for return home after that and got to Berlin easily with a rear tank (plus a reserve). The same is for true any other plane.



A problem is that you _cannot_ use "economical cruise for return home" from many targets in Germany. If you get "bounced" by German fighters while flying at economical cruise it takes way to long to accelerate up to a combat speed. Return speeds need to be at or close to max lean cruise. 

For instance (and just because it is the first data sheet I ran across) a Spitfire MK XIV has a top speed of 448mph at 26,000, an economical cruise of 245mph at 20,000ft and a maximum weak mixture cruise of 362mph at 20,000ft. Now the return might not be made at 362mph but flying at 245mph over Germany is like flying towing a big *kick me* sign. 




OldSkeptic said:


> As for that 15 mins, that is a lot of combat time at full power. Even in combat full power (and maximum consumption) was used only sparingly. Thus the actual combat time could have been longer, with much of it at more reduced power settings. Basically you would have ran out of ammo fairly quickly as well.



In a lot of fights the planes lost altitude fairly quickly and could wind up with the fighters thousands of feet, if not over 10,000ft below the desired altitude. Do the fighters break off and return home or with ammo remaining try to climb back up to the bombers height or above? It depends on where they are ( how close to the next fighter rendezvous), fuel remaining, ammo remaining and how far below/behind the bombers they wind up.


----------



## Neil Stirling (Sep 29, 2013)

Figures in nautical miles, kts and imperial gallons.














Neil.


----------



## drgondog (Sep 29, 2013)

Thank you Neil.. once again RN and RAF a little more thorough in laying out great detail regarding performance than USN published documents that I have been able to find.


----------



## Milosh (Sep 29, 2013)

Am I reading the graphic correctly in that the combat radius is 237nm (272mi)? If so, that would not get the F6F even half way to Berlin.


----------



## bob44 (Sep 29, 2013)

Rufus123 said:


> This is off topic but I am curious.
> 
> The talk of the Hellcats being used in Europe has made me wonder.
> 
> ...



If the Pacific war ended early, I would think the US Navy aircraft would stay in the Pacific as part of an occupation. However, this would free up industry and manpower for the war in Europe.


----------



## Shortround6 (Sep 29, 2013)

Basically the F6F had less internal fuel than a P-47, more drag and a less efficient engine at altitude. If the P-47 was lacking in radius then unless you repeal the laws of physics the F6F will have even less combat radius.
Combat radius being defined by the amount of fuel *after* the tanks are dropped unless " thinking outside the box" means fighting with a fuel tank still attached.


----------



## Neil Stirling (Sep 29, 2013)

Milosh you are 

Neil.


----------



## GregP (Sep 29, 2013)

Here's one back at you: http://www.wwiiaircraftperformance.org/f6f/hellcat-II-ads-a.jpg

You might note this is courtesy of Neil Sterling ...

Note that in column 3, about 2/3 or the way down the page on the left side, with only 333 gallons carried the Hellcat has a range of 1,430 miles (statute miles). I would remind you that Berlin is only 580 air miles (statute miles) from London and is thus WELL within range, unless m y math is wrong, carrying about half of the fuel it CAN carry, so you are coming off as quite disingenuous by continuing to insist the Hellcat couldn't perform escort duties.

I never said it would be optimum or even a good idea ... I said it could be done, and it can, unless you want to refuse to believe the facts. It seems that is exactly what you want to to do, so go ahead. Makes no difference, but you seem to be arguing for the position you took initially without looking at what is possible, which was my "what-if."

It IS possible and could easily be done, using factory specs ... not that they did or even SHOULD have. It was just a damned "what-if" that turns out to be possible.


----------



## Jabberwocky (Sep 30, 2013)

I'd say that part of the problem is the extra conditions that the FAA/RN had when determining combat radius of the Hellcat, and how that differed from the RAF and USAAF’s processes.

If you look at the figures, the Hellcat’s radius is given as only about 20-25% of max endurance range. Not only are there the standard allowances for warm-up, climb to altitude and combat, but there is also a 20 minute allowance loitering around waiting to land on a carrier and 15% allowance for wind, formation flying ect, ect.

On land, these range penalties would not be as severe. The RAF estimated that the low altitude combat radius of the Tempest II/V and P-47 was about 40% of still air cruising range. Allowances were 5 min at take-off power, climb power for 2 minutes, combat power for 5 minutes, fast cruise for 15 minutes, balance at best economy and then subtract a 20% safety margin. 

If we apply the RAF’s range calculations (~40% of still air range) to the F6F, we get a combat radius of up to 470 miles, but for low altitude only. 

I think that’s overgenerous.

Here’s my reasoning:

You’re going to need another 10 minutes or so at higher power levels to get to 25,000 ft. The RAF has only a 5 minute allowance at combat power, rather than the 15 minutes for the RN/FAA. Thus, we might cut the land-based combat radius calculation back to 33-35%.

This would give you a practical radius of about 405-415 miles. That’s better than anything the RAF had and much better than the early P-47s. 

It’s still not enough to get you to Berlin though.

Even if we assume a best-case range of 1430 miles and the (generous) 40% range allowance, then Hellcat’s best combat radius will be 570 miles. With the same calculations, the RAF reckoned that the ‘Thunderbolt II’ could go to a 795 mile combat radius with 2 x 138 gal external tanks, and the Mustang III was good for 725 miles with 2 x 75 gal external tanks. Thus, the Mustang and late P-47Ds have a clear range advantage over the Hellcat.


----------



## drgondog (Sep 30, 2013)

GregP said:


> Here's one back at you: http://www.wwiiaircraftperformance.org/f6f/hellcat-II-ads-a.jpg
> 
> You might note this is courtesy of Neil Sterling ...
> 
> ...



LOL. No.

Go find the SFC for the following for the R-2800-10 or -18.

1. Take Off Power for 2 minutes and then rich for about 25 minutes while 52 other Hellcats take off in pairs (4 spares) and assemble into formation. 
2. Climb to 25000 Feet, level off and throttle up to approximately 330 mph true (you have to be able to catch the Bombers somewhere around Dummer Lake with a 150 gallon tank (extra drag thingy) or if you propose more find the SFC for the equivalent throttle position (increased to overcome the extra drag) to still maintain 330.
3. At RV point Ess at no less than 300mph while flying over a bomber stream at 200mph TAS between Dummer Lake and Berlin. 
4. Engage with LW at Gardlingen or Celle east of Dummer Lake, drop tanks. Explain how much internal fuel you have at this moment. 
5. Fight for 20 minutes at Military and War Power
6. Rejoin bombers from Steinhuder Lake to Berlin assume 330 will still catch up at 25000 feet
7. Return to Dummer Lake where P-47s can RV with you
8. Return to England at least 300mph TAS
OOPs, can't make it past Osnabruck. 

Answer the following questions:
How much internal fuel is used, if at all, while warming up, taxiing, taking off and climbing? What were the SOP for the use of internal versus siphon from tanks for safety reasons. That will impact your already dicey situation when you punch tanks and go Internal fuel of 250 less whatever may have been used during warm up and takeoff.

What was the SFC for Take Off and Climb for a three tank configuration if you propose Ferry Tank configuration for combat escort in ETO.

Greg - you look like a fish flopping in a mud puddle when you keep going back to handbook range tables. Apply the same approach to the P-47D series with 150 gallon tanks in 1943 and ask, if Range divided by two is greater than Berlin radius, then why couldn't it go past Dummer Lake.

Go look up the same info that USAAF provided for Combat Radius for P-40, P-51, P-38 and P-47. They all lay out Lab assumptions based on warm up, take off, climb, cruise, combat, return, 30 minute reserve.

You may miss a couple of really important details regarding USN mission profiles vs ETO/MTO. A couple that come to mind is that Hellcat optimum cruise speed and altitude is around the same figure for SBD/TBF and you rarely ever see them Essing above the navy bombers. Simply because the chances of being intercepted until the target was rare. The courses were straight line, unlike ETO wher huge flak concentrations broke up most routes to target AND the planners were always ziging and sagging on the way to the target to make the LW guess and make mistakes regarding interception.

You keep whining that SR and I are 'not thinking out of the box', that we are bullheaded and refuse to see the crystal clarity of your intellect when you claim 'it CAN be done' but you simply don't know how to prove your thesis. You only resort to published tables for Range when you clearly do not understand the assumptions made for even those figures, nor do you seem to comprehend what must change in your assumptions and calculations to get to a logical fact based argument.

So PROVE your thesis with realistic flight/operations characteristics of an R-2800-10/-18 engine Hellcat as far as Fuel consumption based on climb, high speed cruise at 25000 feet, combat for 30 minutes, high speed cruise back with only the fuel remaining internally from engagement in combat, let down over the Channel, fish around for 30 minutes looking for home because of bad weather.

I've done it, Hop has done it for you in the past as two examples for Mustang and Spitfire. You could at least use the same assumptions for the F6F profile.

Go for it. Quit complaining that we don't get it. 



'


----------



## Shortround6 (Sep 30, 2013)

I would be happy to see even 10 minutes at combat power _or_ 5 minutes WEP and 5 minutes military and 300mph (or 297mph at 20,000ft) to the Dutch/Belgian coast. He can drop 15,000ft crossing the Channel while flying 200mph at that point. Still won't make it.


----------



## drgondog (Sep 30, 2013)

Jabberwocky said:


> I'd say that part of the problem is the extra conditions that the FAA/RN had when determining combat radius of the Hellcat, and how that differed from the RAF and USAAF’s processes.
> 
> If you look at the figures, the Hellcat’s radius is given as only about 20-25% of max endurance range. Not only are there the standard allowances for warm-up, climb to altitude and combat, but there is also a 20 minute allowance loitering around waiting to land on a carrier and 15% allowance for wind, formation flying ect, etc.
> 
> ...



There is another complication to the profile as you have presented it. In the ETO the take off and assembly for a Group sized force took approximately 30 minutes from Start Engine time, through warm up, taxi, military power take off in pairs for 24 to 26 pairs, assembly as each pair joins up, climb out to 25000 feet with max gross weight for another 15 plus minutes, then throttle back to fast cruise. The typical escort cruise was 300 to 330mph TAS at 26000 to 30000 feet or about 3000 to 5000 feet above the bombers for the high escort. Returning to base was dictated by fuel but typically it was the same until let down over the Channel. The 30 minute reserve to land was not conservative for all 48-52 aircraft in good weather and optimistic for bad weather.

The key is how much fuel does your aircraft burn at max boost/rpm for 15 to 20 minutes and how much of your internal tank drain before turning back for home from the air battle location of Berlin (in these discussions). The Hellcat burned a lot more (as P-47) than the Spitfire/Mustang. I have seen data ranging from 400 gallons per hour for the R-2800 at Military Power and 240 gph for the Merlin 1650-7. 

Neither the RN nor the USN subscribed to USAAF bomber/escort Procedures for large, fast and high flying bombers.

Comparing Range and Combat Radius always begs the assumptions made to each step in the profile. When you peruse through Mike and Neil's website you will notice how much more detailed test plans at USAAF and RAF/RN test facilities map out differences in cruise speed settings, miles per gallon at different fuel weights and ordnance loads at different altitudes and the affect on power to maintain different cruise speeds based on external loads.

The USN does not seem to have spent as much time. For escort I assume that the range of a Hellcat with 150 gallon external tank is much the same as a SBD/TBF carrying 1000 pound or more of ordnance and were Ok with same cruise speed as the a/c they were escorting in a straight line - which is far different for ETO escort fighter ops.

Your points are well made.


----------



## syscom3 (Sep 30, 2013)

Even if the Hellcat could fly to Berlin, its just dogmeat on a platter. It wont hold up to repeated attacks from -109's and -190's. Not to mention flak batteries that will be in its way from having to fly straight lines.

Now if we were talking about Corsairs, this might be a more logical debate.


----------



## Shortround6 (Sep 30, 2013)

Using the cube law as a rough estimate it takes nearly twice the power to fly at 297mph as it does to fly at 237mph. Assuming a near identical specific fuel consumption that changes the miles per gallon to about 5/8ths what the 237mph will give you. 

The F6F also has a situation with the supercharger. at 20,000ft is possible to get a bit over 800hp from the engine in low blower lean mixture and no ram? but that drops to 625-650hp at 25,000ft. Kicking the supercharger into high gear can give over 900hp max lean at 25,000ft at 34in and a lower rpm but you do need to figure in the extra power/fuel (change is spc) needed to drive the supercharger. 

There is no doubt that a Hell cat could fly with enough drop tank fuel from England to Berlin and back in calm air. But fighting and making it back at a reasonable speed( *NOT* a speed that it might take two minutes to accelerate to full speed from) on reaming internal fuel is another story. 

Using the USAAC radius conditions the extra 65 gallons of fuel in the later P-47DS was worth about 175 miles of radius on a drop tank equipped P-47. (two 150 gallon drop tanks in both cases) 425 miles compared to 600 miles for the bigger internal tank. Now cut the P-47 to just 250 gallons internal instead of 305. Anybody want to guess what the radius might be? 250-275 miles even with the drop tanks? 
Remember the drop tanks ONLY work going in NOT getting out.


----------



## drgondog (Sep 30, 2013)

Mike Williams has an abundance of performance/fuel consumption, miles per gallon data for P-47.
The extract below is for a P47C-1 with R-2800-18 which is close in SFC to both the -10 and -18 for the F6F-3 and -5
For 305 gallons and standard performance calc - namely warm up, Take off at Military Power, climb to altitudes (10, 15, 20, 25 and 30K), level off and cruise at MAXIMIM cruise range settings (2280 rpm/31.5 "Hg) with provision for 20 minutes Combat at Military Power (2700 rpm /52" Hg) then return at Maximum Cruise distance settings of 2280/31.5 and land with 15 gallon reserve. Start with 305 Gallons.

http://www.wwiiaircraftperformance.org/p-47/p-47c-tactical-inc2.jpg

Greg - take note that this table with the above set of assumptions yields the following:
170 miles Combat Radius at 25 K with 305 at take off. Clean, no external tanks for extra drag, no formation take off and assembly for extra 25 minutes of Normal Rated Power orbit. No provision for throttle jockeying for every body flying formation except Group CO. Everything you see below has the the P-47C and F6F-5 using same fuel consumption as the P-47N in the Williams presented tests. It follows pretty well with the P-47C-1 range as I run the numbers below.

Bring your own data and show how SR and I are complete Naysayers who can't think out of the box.

Note - when you dig further, you will see that Maximum Cruise settings of 1700/33" for P-47N yields a speed of 185 IAS which, at 25K is 260mph TAS which is at least 40-50mph* too slow for ETO escort*. If you can't catch 'em you can't cover 'em.

1. The typical profile would be to fast cruise at 2400/36.0" which would yield 230 IAS/335 TAS. That fuel consumption is about 115gph for the P-47N tables. 

2. Combat fuel consumption = Military Power at 2700rpm (Not WEP) at 52" hg = 290 gph. 20 Minutes of MP = 1/3 od 290 = 97 gallons

3. Warm up, take off, assembly = assume 30 minutes at Rated Power = 162 gallons per hour = 81 gallons

4. Climb to 25K at Rated Power = 18 minutes for a P-47C/Hellcat = .30 x 162 = 19 gallons. Travel approximately (conservative) @160mph x .3 hr at 45 degrees = 48.6 gallons to get to 25,000 feet at rated power*NOTE -at 18 minutes to climb 25000 feet the actual climb angle is about 1:10 so the P-47C/F6F travels about 45 miles toward Zwolle*

5. Set course for Zwolle Hooland ~ 200 miles away, to RV, at 115 gph. 200/335 = .6 hrs at 115 gph = 68 gallons

At this point 380 miles from Berlin the P-37C-1/Hellcat is essing over the bombers travelling 205-210 mph. The bombers will reach Berlin 380/210 in 1.8 hours. Fuel = 1.8 x 115gph = 208 gallons.

Pause for a moment. Assume a 250 gallon external tank, not one drop of the 250 gallon internal tank was used to warm up, take off and climb - all external. 97 plus 81 plus 67 means that the F6F/P-47C with 150 gallon tank ran out between the English Coast and Zwolle Holland. Between Dutch coast and Zwolle the P-47C and F6F dropped external 150 gallon tank and by the time they reached Osnabruck they have consumed 70+ gallons of their internal fuel (250-70 for Hellcat, 305-70 for P-47C). 

So - at Osnabruck in weast Germany the Hellcat/P-47C with similar R-2800 engines have 180 and 235 gallons remaining assuming they used 150 gallon external tanks at 25000 feet. The F6F and P-37C used 220 gallons each to get to Osnabruck.

At this point if the Hellcat turns for home it might make it by leaning all the way back to 2280/31.5", but the B-17s will be unescorted fro the next 280 and back.

I did this pretty fast and welcome corrections to the math, but Greg

IF you want to take shots go get the facts on sfc for the Power Ratings at each stage.


----------



## OldSkeptic (Sep 30, 2013)

Neil Stirling said:


> Figures in nautical miles, kts and imperial gallons.
> 
> Neil.



Thanks Niel, backs up the reasonableness of my LR Spit calcs, ie allowance for takeoff, climb and 15 mins combat.

As for SR comments, well even at economical cruise a LR Spit (VIII variant) could easily catch the bombers again and climb back up again. You are probably talking about a 1-1.5 hour escort phase (after rendezvous), of which a 15 mins combat allowance is a lot...

As for return to base at MEC, the calc I used was at 20,000ft, ideally you'd climb to that (or even a bit above) then lean out and slow down for the return. Pretty immune, plus the Luftwaffe (correctly) is focusing on the bombers and is not going to waste planes and time climbing up to do an intercept with a bunch of fighters. At that altitude, even if getting a bit short on fuel, all they have to do is go into a shallow dive to pick up speed and leave the intercepting fighters behind (which have their own fuel issues). Plus you have a 100 mile reserve allowance for just this sort of eventuality and can, for a short time, crank up the speed if necessary. So, for example, a shallow dive and move to fastest economical cruise for say 5-10 mins, until you have left them behind and can slow down again.

Don't forget, another bunch of fighters have now taken over the escort position, which the defending fighters also have to deal with.

Now my calcs show that Berlin was about the limit for a Spit VIII LR variant (unless you maybe drop the 0.303s and add more fuel there* and/or have a slightly bigger rear tank and leave about 10-15 gals in it as a reserve, CoG would still be ok at that, I conservatively assumed *all *rear tank fuel being used), but still doable with careful planning and training, tight though. But for shorter missions (which were by far the majority, say around the 400-450 mile radius) it could be done easily with a much larger reserve for all those eventualities.

* If you delete the 0.303's and add even just 7 gals in each wing in that space (less room there) then the reserve fuel goes to 29 gals, or 198 miles at MEC. Add 10 gals left in the rear and it is now 39 gals or 268 miles at MEC. All gals UK ones of course.


----------



## Shortround6 (Sep 30, 2013)

Please note that it takes the P-47 25 gallons of fuel and 7 minutes to climb from 15,000ft to 25,000ft using 2550rpm and 42" map.( max continuous 1625hp=210 gal an hour) Granted that is at 12,500lbs. Climbing slower actually burns more fuel because it takes longer to get to altitude ( see fuel used in "ferry" climb). Time will be quicker using military power but fuel burn increases by about 1 gallon *per minute*. 
A P-47D (early) could take about 5 minutes to climb from 15,000ft to 25,000ft using 2700rpm and 52-50in map burning 275 gallons an hour or 4.58 gallons a minute. 

A fighter _can_ use a fair amount of fuel just getting back into position or back into the fight without actually engaging in _constant_ combat for 15-20 minutes.

Again, thanks to Zeno's for the chart.


----------



## OldSkeptic (Oct 1, 2013)

Yep, which an issue in combat for the P-47, especially close to its max range. One dive and you are out basically..


----------



## GregP (Oct 1, 2013)

Hi Drgondog,

I already did. It's in the posts.

You seem to forget that Naval ranges are VERY conservative. The carrier moves around, often without the knowledge of the WWII aviator. So the Navy has a requirement for a LOT of reserve fuel. The fighter must fly the misson, come back, look around for 30 - 45 minutes and then spend 15 - 45 or more minutes in the pattern to land while the other guys recover.

It is trite to say, but land bases don't move around much and the reserves are therefore much less. 

The specs SAY it, the Hellcat CAN fly a 1,200 mile trip with adequate reserves if flown from a gound base, and I won't revisit this again. It absolutely CAN be done.

Your analysis is very flawed ... ask any Hellcat pilot. I have.


----------



## wuzak (Oct 1, 2013)

GregP said:


> The specs SAY it, the Hellcat CAN fly a 1,200 mile trip with adequate reserves if flown from a gound base, and I won't revisit this again. It absolutely CAN be done.



At _Most Economic Cruise_ speed.

Which will:

not allow you to catch the bombers unless you leave at the same time
leave you at a disadvantage against the defenders
and since you will be flying lower than the bombers you might want to look up near the target zone in case one of the bombs has your name on it!


----------



## wuzak (Oct 1, 2013)

Shortround6 said:


> For instance (and just because it is the first data sheet I ran across) a Spitfire MK XIV has a top speed of 448mph at 26,000, an economical cruise of 245mph at 20,000ft and a maximum weak mixture cruise of 362mph at 20,000ft. Now the return might not be made at 362mph but flying at 245mph over Germany is like flying towing a big *kick me* sign.



If I were in a bomber needing escort, I would prefer that the brass is spending their time working out how to get a Spitfire XIV over target rather than a Hellcat!

And would RJ Mitchell have ever conceived that his Spitfire would, in but a few years, be able to cruise faster than it was originally able to do in all-out level flight?


----------



## GregP (Oct 1, 2013)

Hi Wuzak, I came back because YOU were here only.

I specifically say that if Hellcats were the only option, it could be done. I would NOT choose the Hellcat for the mission but, if it were the only option, it absolutely COULD be done.

The Hellcat COULD takeoff with 600 US gallons of fuel if required, and that bis WAY more than required. Combat and return can be debated a small bit but, if the Hellcat were the only option, it could have been done easily, agreement from any of you or not. I've spoken with WWII Hellcat pilots who flew 1,5000 miiles WITH guns loaded, and THEY weren't part of this discussion and had no axe to grind.

Sorry for all you nay-sayers, but it IS possible for a Hellcat. I have not and WILL not figure it for a P-47/ This discussion is much too ridiculous for me to want to continue.

Hell, they loaded the P-51 beyond aft CG and flew it that way for a few YEARS. You think they would not have done so to the F6F ?

Get real.


----------



## wuzak (Oct 1, 2013)

If Hellcats were the *only* option they may have been able to make it work. Not sure it would have been much better than no escort (or more properly, no escort over the target area, but escort part of the way there).


----------



## OldSkeptic (Oct 1, 2013)

Agree Greg, if it was absolutely necessary they would have done it ...though the losses would have been terrible.

Wuzak is correct, better to trick up the MK VIII (or IX) or even XIV Spit first, or bring on the DH Hornet sooner if for some reason the Mustang is not available.
The superiority in performance (plus the lower fuel consumption, hence the extra fuel load required is less) make it a better platform for that sort of mission.

You are dead correct to bring up the CoG issue (an issue the anti=-Spit crowd bang on and on about all the time), but that applied to lots of aircraft in wartime. For example Mossie (and possibly PR ones) bombers were often starting off with poor CoG, which of course improved as they burned off fuel.

If you are in non-contested airspace to burn off enough fuel to stabilise the aircraft it is not (with good training of course) such an issue as some people think.
It is hard work as the aircraft can 'hunt' all the time and you must be very careful in turns (or pulling out of dives) so you won't do excessive G, as it wants to tighten up.

But training helps a lot, plus things like bob weights and the like.

Plus take off and climb to 20,000 ft on a Spit LF IX took alone (at full LR weight) about 24 gals, a Mustang IV about 30 UK ones). Who knows what a P-47 was*, 50% more at least (maybe double?).
So you were starting to get back to normal well before you got into enemy territory.

Form what I read the Mustang got much better after half the rear tank was ran down, the Spit once you got down to about 20 gals (a third of a 66 gal tank) in the Merlin 60 series with the elevator horn balance fixes (and the XIV was probably a little bit better due to the greater weight in the front). So the Mustang was better (and had more fuel anyway in the main tanks), but fully fueled up it was severely out of CoG balance on take off.

Added: Found it, P-47 normal climb with drop tanks a whipping 70 UK gals.... ouch. 84 gals with the belly tank as well... double ouch.


----------



## tomo pauk (Oct 1, 2013)

Anyone contemplated how good/bad would be the the Spit VIII, when fitted with 29 imp gal rear tank, as per Spitfire V used for deployment in the Med? Almost 180 US gals total - what would be realistic combat radius? Either 90 or 170 imp gal slipper tank attached, or maybe 126 imp gal tank from P-38s?


----------



## drgondog (Oct 1, 2013)

Greg - you keep flailing because a.) you don't know how to get the data, and b.) you don't know how to calculate a mission profile when you have the data.

Now - the P-47C-1 had EXACTLY the same R-2800-10 engine (*Incorrect thanks to Wuzak - it was a -21 with single speed/single stage and supercharger but the sfc was still close - in favor of the P-47 at altitudes above 25,000 feet*), as the F6F with very close sfc. Redo my analysis using your assumptions for fuel to mile consumption based on climb to 26,000 (non conservative), fast cruise to R/V, slow down to escort at 300+ mph, combat at MP for 20 minutes, return at same cruise as escort. 15 minutes of fuel left as reserve at your airfield (bonus - the P-47C-1 Combat radius of 170 miles with no external tanks - or additional drag - was with only15 minutes reserve) 

Remember the R2800-10 at MP burns 280-300 gph at MP at 25000 feet so the Very best case is that you drain 100 gallons of internal fuel and have no drop tanks over 600 miles from home. You have 150 gallons left minus whatever you used for warm up, taxi and formation assembly minus 15 minutes at auto lean ~ 115gph or say 30 gallons.

*Net - show what ya got for the R2800-10 to go 600 miles on 120 gallons of fuel.*

BTW - collar your WWII Hellcat vet and have him tell you what mission he flew, or heard of, to escort ANY aircraft flying 150IAS/210TAS at 25000 feet for some 600 miles out and 600 miles back with a fight over the target. Report back with That story and maybe supply a name and contact - or invite him to join us and put me in my place?


----------



## drgondog (Oct 1, 2013)

tomo pauk said:


> Anyone contemplated how good/bad would be the the Spit VIII, when fitted with 29 imp gal rear tank, as per Spitfire V used for deployment in the Med? Almost 180 US gals total - what would be realistic combat radius? Either 90 or 170 imp gal slipper tank attached, or maybe 126 imp gal tank from P-38s?



Tomo - somewhere back in time we did one of these with the 170 imp gal tank with assumptions that the extra drag would require a cruise setting higher than Max Range setting - IIRC offhand it could get 600+ with no combat.


----------



## Shortround6 (Oct 1, 2013)

GregP said:


> I specifically say that if Hellcats were the only option, it could be done. I would NOT choose the Hellcat for the mission but, if it were the only option, it absolutely COULD be done.



Not with the escort mission profiles as done historically. 

which leaves us with........

Have the bombers fly at lower altitudes so the F6F can fly top cover. Of course this puts then into more flak. but hey, lets think outside the box. 

Use scads more F6Fs so some F6Fs are escorting other F6Fs which won't drop their tanks until later. 



> The Hellcat COULD takeoff with 600 US gallons of fuel if required, and that bis WAY more than required. Combat and return can be debated a small bit but, if the Hellcat were the only option, it could have been done easily, agreement from any of you or not.



You don't seem to grasp the idea that that the amount of fuel you take off with is irrelevant, it is the amount you have after you drop the tanks that counts, otherwise your escorts are flying one way, semi suicide missions. _outside the box_ but hardly effective in the long run. Lets look at the P-47 _because_ we have figures for it. 

305 gallons = 125 mile radius
370 gallons = 225 mile radius
605 gallons = 425 mile radius ( two 150 gallon drop tanks) 
670 gallons = 600 mile radius ( two 150 gallon drop tanks) 

Please note that an extra 235 gallons of fuel extends the radius 200 miles with the smaller internal tank ( or 300 gallons got an extra 300 miles) while the extra 65 gallons internal extended the radius 100 miles with no drop tanks and is good for 175 miles with the drop tanks. 

Also please note that a P-47 could fly 830 miles on 250 US gallons _after_ warm up, take off and climb to 5,000ft at _economical_ cruise. 
USAAC planners were trying to figure out how to get the pilots and planes *back* to use on future missions. 



> I have spoken with WWII Hellcat pilots who flew 1,5000 miiles WITH guns loaded, and THEY weren't part of this discussion and had no axe to grind.



Great, now ask them if they flew that distance at 20-25,000ft doing 210mph IAS or 300 mph true. 



> Sorry for all you nay-sayers, but it IS possible for a Hellcat


.

Somehow it is only possible on your "say so". you have offered *NO* proof that is was possible at the speeds and altitudes needed for the ETO escort mission. 
No disrespect to the veterans that flew the F6F but if you don't ask the right question you will not get the right answer. 
Sorry Greg, without "Pixie dust" or anti-gravity paint it is NOT possible. 



> This discussion is much too ridiculous for me to want to continue.



Something we agree on, you bring NO facts to the table. No charts, NO tables, No flight plans, NO historic missions _flown_ at the altitudes and speeds needed. 



> Hell, they loaded the P-51 beyond aft CG and flew it that way for a few YEARS. You think they would not have done so to the F6F ?



well, finally a somewhat valid suggestion. Lets just _ADD_ 120 gallons behind the CG to get the the return profile close to the P-47s ( and ignore that the P-51s seldom, if ever, fought with the rear tank more than about 25-33% full).
Now what does an extra 720lbs of fuel + weight of the self sealing tank) do to the performance of the Hellcat at 20-25,000ft? 



> Get real



If the shoe fits..........


----------



## Shortround6 (Oct 1, 2013)

drgondog said:


> Now - the P-47C-1 had EXACTLY the same R-2800-10 engine as the F6F with very close sfc.



I beleive there is a difference and not in Hellcats favor. 

The engine in the P-47 can supply 1200hp at 2250rpm/32in at 25,000ft burning 105 US gallons an hour and/or
1100hp at 2150rpm/31" at 25,000ft burning 95 US gallons an hour

The engine in the F6F needs to turning 2250rpm at 35" to deliver just under 1100hp to the prop at 25,000ft in high gear and about the same in low blower, 25,000ft being sort of a crossover point at this level of power. But slightly more rpm and more MAP for the same power to the prop can hardly be the same spc can it? 

Add to that the engine chart for the F4U (P&W R-2800-8 differed from the -10 in the F6F in the type of carburetor used) 

Gives max cruise ratings of 970hp at 2150rpm/34" at 20500ft and 93 US gallons an hour low blower and 930-950hp( chart is a bit fuzzy) at 2050rpm/34" at 26000ft in high blower at 82 gallons an hour. 

With my math it seems the navy engines and the P-47 engine are either very close or a the Navy engines are a few percent behind.


----------



## drgondog (Oct 1, 2013)

OldSkeptic said:


> Agree Greg, if it was absolutely necessary they would have done it ...though the losses would have been terrible.
> 
> *So far - lots of arm waving but no facts. The F6F-3 had the same engine as the P-47 but not turbo supercharged nor perform as well above 25000 feet, nearly the same weight and I presented the calculated Combat ranges for 25000 and 30000 feet. The P-47C calcs used only 15 minutes of reserve for landing whereas the USN had an hour IIRC and the P-47C-1 used a 20 minute combat at MP only (no WEP) and had 305 gallons internal to the F6F 250. Combat Radius 160 to 170 miles. F6F-3 will be no better on 305 gallons internal fuel and far worse on 250 gallons. Discount external fuel because on remaining internal fuel will get you home once you engage in a fight - unless you are a very stupid fighter pilot choosing to fight slow and sluggish against a 109 over Berlin.
> 
> ...



Add another 30 minutes at 115gph+ to assemble a 52 ship formation and you will get to 126 gallons - I calculated 129+ above.


----------



## drgondog (Oct 1, 2013)

Shortround6 said:


> I beleive there is a difference and not in Hellcats favor.
> 
> The engine in the P-47 can supply 1200hp at 2250rpm/32in at 25,000ft burning 105 US gallons an hour and/or
> 1100hp at 2150rpm/31" at 25,000ft burning 95 US gallons an hour
> ...



The differences are miniscule. The hidden factor for these discussions is the question "What is the most economical rpm/boost setting to maintain 325-340 mph TAS at 26000 to 30000 feet?"

That is how I got to 2400/36" and 115 gph.


----------



## wuzak (Oct 1, 2013)

drgondog said:


> Now - the P-47C-1 had EXACTLY the same R-2800-10 engine as the F6F with very close sfc.



From Graham White, _R-2800, Pratt Whitney's Dependable Masterpiece_ the P-47C-1 was fitted with the R-2800-21. This was, of course, a single stage, sigle speed engine, whose altitude performance was due to the turbocharger.

The F6F used the R-2800-10, which was a 2 stage 3 speed (low, high and neutral) supercharged engine.

Since the F6F's engine required a higher pressure a ratio from its mechanically driven supercharger at altitude than the P-47's did it would have worse fuel consumption, I would think. So that would make the comparison worse for the F6F.


----------



## drgondog (Oct 1, 2013)

GregP said:


> Hi Drgondog,
> 
> I already did. It's in the posts.
> 
> ...



My analysis is sound - I don't have to ask a Hellcat pilot. You have no analysis and you can't find one in USN records to perform an ETO escort to Berlin on a rational basis... the way those nasty old generals would insist on.

Go find your analysis - that you claim to have posted - so that we may bask in the light of your brilliance. I know you must have uncovered the 'thing' that neither SR or I have failed to discern..


----------



## drgondog (Oct 1, 2013)

wuzak said:


> From Graham White, _R-2800, Pratt Whitney's Dependable Masterpiece_ the P-47C-1 was fitted with the R-2800-21. This was, of course, a single stage, sigle speed engine, whose altitude performance was due to the turbocharger.
> 
> The F6F used the R-2800-10, which was a 2 stage 3 speed (low, high and neutral) supercharged engine.
> 
> Since the F6F's engine required a higher pressure a ratio from its mechanically driven supercharger at altitude than the P-47's did it would have worse fuel consumption, I would think. So that would make the comparison worse for the F6F.



Wuzak - you are correct. I misread my own notes. All the P-47B and C models tested at Eglin had the R-2800-21.


----------



## OldSkeptic (Oct 1, 2013)

tomo pauk said:


> Anyone contemplated how good/bad would be the the Spit VIII, when fitted with 29 imp gal rear tank, as per Spitfire V used for deployment in the Med? Almost 180 US gals total - what would be realistic combat radius? Either 90 or 170 imp gal slipper tank attached, or maybe 126 imp gal tank from P-38s?



Plugging the numbers into my spreadsheet and using a 90 gal drop tank) you get about 450miles radius. That includes
(1) Allowance for take off an climb to 20,000ft (using rear tank).
(2) Cruise to target (MEC) at 20,000ft (using drop tank).
(3) 15 mins Combat (internal fuel)
(4) Return (internal Fuel)
(5) Reserve of 22 gals (enough for 151 miles at MEC or another 10 mins at combat).

Obviously higher altitudes, etc will reduce that, say for a 25,000ft mission then 400 miles.

No need for a larger drop tank, what matters is what is left in (non CoG affecting) internal fuel after getting there and combat (15 mins = 35 gals) which on a Mk VIII is 87 gals.

You want to improve the combat radius then you need more internal fuel that does not affect performance, say some more in the wings (take out the 0.303s) or 10 gals left in the rear tank (probably acceptable with a bob weight). Even the option, used in some PR versions, of an under the seat tank (10-20 gals perhaps).

You take off, climb and cruise to target (or escort rendezvous) on the rear tank and the drop tank. Hold the drop tank until combat (SOP), then fight and return on what is left.



Edited to add: For the sheer heck of It I set up the Mustang with the same formulas (based on the aircraft data sheet) and it is interesting.

Now, for comparison I set up a 500 mile combat radius for a LR Spit MK VIII vs P-51D. Same assumptions.

For return the Spit has 87 gals and the Mustang 114 (UK of course) only 27 gals diff.

But, the Spit has only 101 miles (at MEC) as reserve, while the Mustang has 343 miles up its sleeve.

The reason is the lower drag (despite its higher cruise speed gives a lower fuel consumption.

On the way out the consumption is about the same in total, the Spit uses less in the climb but more on the cruise there. The Spit uses a bit less for combat.
But on the way back (and in a clean configuration) the Mustang has about 7% lower fuel consumption. Over 500 miles return that adds up to a much larger reserve left (or a longer return range).

Even on the same internal and external fuel load (though how you'd fit it into and on the Spit ...) the Mustang has a longer range. 
When you take into account it's actual larger internal then on a realistic basis (and same assumptions) the Mustang has a larger reserve left for a 700 mile radius mission than a LR Spit VIII at 500 miles. Plus that faster MEC cruise speed for the Mustang doesn't hurt either (253 mph vs 220).

As for forming up, etc on the way there, in neither case is than an issue affecting max range, since it is done on the rear tanks and the drop tank. 
For the Spit, even for a 500 mile mission with a 90 gal drop tank, only 37 gals from the drop tank is used on the cruise, leaving plenty for forming up, etc and (of course) the actual escort phase where you will be zig zagging, etc (eg you might rendezvous at the 300 mile point and escort for 200 miles). 

The Mustang is naturally even better with it's larger drop tanks and lower consumption.


----------



## drgondog (Oct 1, 2013)

OldSkeptic - if your mission is escort there is the factor for formation assembly for both Mustang and Spitfire.

The Spit and Mustang III frequently had 12 ship assignments whereas the US Mustang had 48 aircraft in a Fighter Group mission (plus spares0.

That would add at least 10 minutes for the Spit and 30+ minutes for P-51B/D at combination Rated and military power.

You also should reserve 25+ gallons in the rear tank unless the mission is relatively short like to Brunswick or Mulhausen.


----------



## OldSkeptic (Oct 1, 2013)

drgondog said:


> OldSkeptic - if your mission is escort there is the factor for formation assembly for both Mustang and Spitfire.
> 
> The Spit and Mustang III frequently had 12 ship assignments whereas the US Mustang had 48 aircraft in a Fighter Group mission (plus spares0.
> 
> That would add at least 10 minutes for the Spit and 30+ minutes for P-51B/D at combination Rated and military power.



All done on rear and drop tank. Even in a 700 mile mission the Mustang has 61 (UK) gals free in its drop tanks for that sort of thing (after takeoff, climb and cruise). 
There are 196 gals in its rear and drop tanks, more than enough for takeoff, climb, forming up, cruise, zig zagging, etc, before you hit the internal wing tanks for combat and return.


----------



## drgondog (Oct 1, 2013)

Not arguing your point about fuel to say, Berlin. But going to Posnan or Stettin or Piryatin, Ukraine sets different operating procedures for both uses of aft fuselage fuel and cruise settings. My only point is that for your spread sheet that you start using internal fuel on assembly and climb and check when it is near 30 gallons - then switch to External fuel. 

The experienced guys had to be constantly aware of the use of the externals to try to balance the usage as much as possible.

I know my father kept 50 gallons in his aft tank for the last shuttle mission, confident in his ability to fly the Mustang on the ragged edge of stability - just to make sure he had enough fuel. His directive to the shooters were to hit 'em but don't chase 'em if they broke for the deck in order to reduce the combat allowance.

He touched down after 8 hrs with 35 gallons left primarily because of confusion with Bomb Wings who reported being late, then 30 minutes later ahead of schedule so the group had to speed up the cruise to get to R/V point Nw of Warsaw.


----------



## OldSkeptic (Oct 1, 2013)

Oh yes, that's why I call the Mustang a VLR fighter. And agree about leaving some rear tank fuel. 20-30 gals for a Mustang was quite possible and done for those very long range missions.

My spreadsheet can take account of that, for a 700 mile mission (eg) of you run the rear totally down at the beginning you have only 19 gals (or 143 miles at MEC) in reserve, not a lot. 
But if you leave 20 gals in the rear tank then you have 39 gals (291 miles) which is a lot more comfortable. Even doing that you still don't use all the drop tank fuel in pure cruise, with 41 gals up your sleeve for formatting, zig zagging, etc.


----------



## Milosh (Oct 2, 2013)

OT

All this talk of drop tanks has me thinking about the internals of the drop tank. Was there any kind kind of baffling inside the tank to stop the fuel from sloshing around?


----------



## drgondog (Oct 2, 2013)

Milosh said:


> OT
> 
> All this talk of drop tanks has me thinking about the internals of the drop tank. Was there any kind kind of baffling inside the tank to stop the fuel from sloshing around?



I don't recall that either the 75 or 160 gallon metal tanks had baffles. The 110 was made of reinforced impregnated paper made in UK and I just don't know.


----------



## Greyman (Oct 2, 2013)

The Hurricane's drop tanks had baffles. Unsure about other types.


----------



## bobbysocks (Oct 2, 2013)

i dont see where baffles would have come into play. not saying they did or didnt have them..just trying to rationalize this out. the only sloshing back and forth would occur on the ground taxiing or during take off and they were filled to capacity and wouldnt slosh then anyways. when flying you didnt do violent or quick maneuvers while they were attached...turns were shallow...etc. rough air after the drop tanks were partially emptied could give you a little shift but how much??


----------



## Aozora (Oct 2, 2013)

For interest here is an Australian report on the drop tank used on the A6M series up to the early A6M5 (probably from an A6M3):

































What's interesting is how well constructed it was and the fact that the feed pipe was deemed to be to small to feed an engine developing full power.


----------



## tyrodtom (Oct 2, 2013)

Any droppable fuel tank in the 50-100 gal range is going to have some type of inner structure, that at a side benefit would also function as baffles.
You can't just have a thin metal skin, or any other material, fill it with 400 lbs and up of liquid, just put lugs on it and hang it under a wing. There has to be some kind of inner construction in that tank to transfer the load to the lugs.

Even the napalm tanks I assembled in the USAF had pretty substantial bulkheads internally, they would have functioned somewhat as baffles, though cured napalm has no need of baffles in the tank.


----------



## Aozora (Oct 2, 2013)

tyrodtom said:


> Any droppable fuel tank in the 50-100 gal range is going to have some type of inner structure, that at a side benefit would also function as baffles.
> You can't just have a thin metal skin, or any other material, fill it with 400 lbs and up of liquid, just put lugs on it and hang it under a wing. There has to be some kind of inner construction in that tank to transfer the load to the lugs.
> 
> Even the napalm tanks I assembled in the USAF had pretty substantial bulkheads internally, they would have functioned somewhat as baffles, though cured napalm has no need of baffles in the tank.


 
Definitely; baffles of some description would be needed because there was never any guarantee that flight manouevres would be gentle enough to prevent the petrol slopping around in large quantities. Try filling (say) a five gallon container with 3 gallons of petrol, swing it gently from side to side until the petrol sets up a momentum of its own, then try holding the container steady while gripping the handle in one hand. Once unbaffled liquid starts moving it can be very hard to stop.


----------



## drgondog (Oct 2, 2013)

Greg has been pretty quiet since Shortround nailed him for umpteenth time on the difference between Range vs Combat Radius and my pointed remarks about the difference in fuel consumption for a Hellcat at 30000 feet and 340mph to escort ETO bombers vs 15000 feet and 205 mph True escorting SBD's.

Wonder if he has recovered yet. Wonder if he has decided to do some research and applied math. Wonder if he can do either and apply to the question he posed?


----------



## bobbysocks (Oct 2, 2013)

with the paper tanks... they broke down after awhile due to the fuel in them. any baffle would have to be a different material or you risk contaminating the fuel with the adhesive and construction material as it particalizes. those would, of course, be caught by the fuel filter but could/would probably clog it up. were the main tanks...wing and fuse baffled? i know they had a bladder of self-sealing rubberized material that acted to seal up holes...... but once fuel had been run down in those tanks and the bladder was smaller than the inside area of the tank...what kept it from it from rolling around inside that metal tank? and if they werent baffled...what would make it neccessary to baffle drop tanks?

my light sport ac has 2 wing tanks that arent baffled. its a really light ac and is more at the mercy of thermals and winds aloft than a heavy ww2 fighter so if that was going to affect flight i imagine they would have baffled them.


----------



## Njaco (Oct 2, 2013)

Lets not start looking for a fight.


----------



## syscom3 (Oct 3, 2013)

Lets just leave it at this. The Hellcat was a great naval aircraft that did what it was supposed to do. Namely escort naval strike missions over the ocean. It was never intended to escort heavy bombers over heavily defended airspace.

The Hellcat would have been chopped up and spit out as an afterthought had it gone up against LW units.

Now, if we are talking about the Corsair doing heavy bomber escorts; well now that's something that's believable and quite possible.


----------



## drgondog (Oct 3, 2013)

I agree - although the fight had been in progress for some time. Enough is enough


----------



## Shortround6 (Oct 3, 2013)

How the Hellcat would have fared in combat is a different question. 

The Corsair, _unmodified_ has the same problem as the Hellcat. Insufficient "protected" internal fuel capacity for the escort mission. 

It doesn't matter what drop tanks you can hang on it. What matters is the 237 gal internal tank. The wing tanks (57 gallons each) were protected "historically"' by a carbon dioxide purge system which kept them from catching fire (or greatly reduced the fire risk) but did nothing to stop them from leaking if hit by small caliber bullets/fragments. Fuel leaks out=plane doesn't get home. 
Now, perhaps, smaller self sealing tanks could have been put in the same spaces to increase the internal fuel a substantial amount and get the radius for the Bomber escort mission up to a usable number. An extra 80-100 gallons depending on tank shape, thickness of self sealing, weight of tanks,etc?
It doesn't seem like that a big a deal, space is there, it is on or near the CG. The Plane is supposed to have a bit less drag than the F6F which helps.


----------



## drgondog (Oct 3, 2013)

The Corsair had a dramatic drop off in power at 25000 feet, although not much worse than the P-51D, but significantly more than the P-51B with critical altitude at 29000 feet.

The F4U like the F6F cruised best much lower altitudes than P-38, P-47 and P-51. Most of the reports I have just looked at for F4U-1 show max endurance at 179.5 mph at 5,500 feet with 237 gallons internal fuel. The F4U-1D however had 361 gallons of internal fuel so it was directly comparable to the P-47D-25 and later models.

The question between the F4U-1D is the difference between cruise fuel consumption when it moves 20,000 feet higher than optimum and boosts to at least 120mph more airspeed at that altitude. Both models I looked at had WI R-2800-8W two speed, two stage superchargers.

I conclude that with 111 more gallons of internal fuel and higher speed at same Rpm and boost that all versions of F4U were superior choice for ETO consideration. That is just with respect to range, much less survivability against the Fw 190 and Me 109 above 20,000 feet.


----------



## Shortround6 (Oct 3, 2013)

Could you check your sources?

In one manual it says that the F4D-1D did NOT have the wing tanks the earlier versions did but could carry TWO drop tanks instead of one. 

Manual says wing tanks were 63 gallons each instead of the 57 gallons each in Deans "AHT" but that may be usable vs total or design vs actual? 12 gallons not enough to get exited about out of 350gals+. 

Range chart in manual also makes NO allowance for warm-up, take-off, or climb to even 5,000ft.


----------



## drgondog (Oct 3, 2013)

SR - America's One Hundred Thousand was my 'quick' one stop reference. Page 507 with discussion of migration from 271 gal (wing only) in XF4U-1.. 

Then F4U-1, -1A, -1C went 273 fuselage only, plus two 62 gallon internal wing tanks for the 361 plus 175 centerline. It looks like the D dropped back to 237 internal (as you noted) plus two 150 gallon external. I misread the table on page 508

So, I stand corrected. Only the F4U-1, -1A and -1C could be tasked for same mission as P-47D-25 and still have enough internal fuel as the 370 gallons in the late model Jug. The F4U-1D would have less than either Hellcat internally.

On USN Range - I agree. Many Range estimates for different combat orgs assumed taxi, takeoff and climb to altitude then throttle back to maximum range throttle and rpm - but I have seen some that make no reference to 'how' the ship got to altitude and seemed to assume some mid air refueling.

ALL USAAF Combat Range profiles have warm up, taxi, take off, climb and throttle back plus 20 minutes combat power - but even those do not have an ETO style group assembly before climb..


----------



## Shortround6 (Oct 3, 2013)

drgondog said:


> Then F4U-1, -1A, -1C went 273 fuselage only, plus two 62 gallon internal wing tanks for the 361 plus 175 centerline. It looks like the D dropped back to 237 internal (as you noted) plus two 150 gallon external. I misread the table on page 508
> 
> So, I stand corrected. Only the F4U-1, -1A and -1C could be tasked for same mission as P-47D-25 and still have enough internal fuel as the 370 gallons in the late model Jug .



As "issued" the wing tanks were protected against fire by a CO2 dilution system to displace the flammable vapor in the tanks. The wing tanks were not protected against leakage. Had it been wanted I would guess the the wing tanks could have been replaced with self-sealing fuel tanks at some drop in capacity but still giving between the 305 and 370 gallons of the P-47s. 
High speed cruise at 25,000ft and performance at 25,000 is still up for question.


----------



## tomo pauk (Oct 3, 2013)

US Navy tested the Fw-190A-4 vs Hellcat Corsair. At 25000 ft, the 190 was found to be faster 6 mph vs. F4U and 19 mph vs. F6F - the F6F really has nothing to offer with F4U around. The 190 was with 2 cannons and 2 LMGs aboard. Here.


----------



## drgondog (Oct 3, 2013)

Here is an encapsulation of the debate: 

Postulate - F6F-3 could have performed the bomber escort role in the ETO during WWII as far as Berlin.

Given:
F6F-3 with R2800-10, 250 Gallons of fuel internally, two 150 gallon tanks externally is the proposed 
Mixture of two US Bomber Types. B-17s with average altitude of 26,000 feet (TAS ~210 @ 150 mph IAS) or B-24s at 22,000 feet (TAS at 237 mph @ 180 IAS)
Assumptions:
1. Bomber course - East Anglia to Zwolle, Zwolle to Celle, Stendal and Berlin in straight line. Total = 580 miles.
2. Fighter R/V for final Target escort after Penetration Support turns for home. R/V just north of Hannover, west of Celle.
3. Fighter Route - East Anglia toward Amsterdam to Zwolle, (~270 miles), Zwolle to Hannover (~150 miles), Hannover to Berlin (~155 miles).
4. Combat Radius Profile
a.Warm up for 5 minutes 
b. 1 minute take Off (MP) power - Combined warm up/take off equivalent to 5 minutes Rated Power ~ 25 minutes while all 48-52 ships form up into Group formation
c. Climb to 25,000 feet at 160 IAS and proceed along bomber course (there is a reason for this, except for some unique missions) at 210 IAS 
d. At R/V climb to 30,000 feet and Ess over bombers at 210 IAS .
e. Escort to Berlin and back to same R/V point to hand off to Withdrawal Support
f. Cruise Home
g. Orbit for 30 minutes as rest of the Group lands.
h. Be Non Conservative - No Reserve - Land on fumes or display how much fuel you have left

Options 
Cruise at any speed you choose but a.) must be able to R/V with bombers traveling at 210 mph at 26,000 feet from point halfway between East Anglia and Amsterdam all the way to Berlin, b.) Cruise above the bombers in central escort 4000 feet above them, c.) Cruise in Ess or straight line if you choose to drop your airspeed to bomber speed but be conscious of grave threat to your ability to protect against fighters entering at 390 mph+ TAS with altitude advantage. d.) Drop tanks for Combat at Combat Power (not WEP) for 20 minutes. e.) cruise home any way you can at any altitude and power settings you choose.
5. Reserve 30 minutes of fuel for circling airfield while the rest of the group lands.

Required:

1. Power settings, rpm, fuel rate of consumption, altitude and airspeed for each stage of the mission profile
2. Fuel remaining in external tanks (if any) at Berlin
3. Fuel usage from internal 250 gallon tank during taxi, TO and Formation assy
4. Internal fuel remaining over Berlin when entering Combat.

Argument(s) against the F6F-3 or -5 achieving suitable USAAF ETO Bomber escort to and from Berlin.
1. Altitude and ETO cruise requirements for the F6F vs P-47C, as one example, force the F6F from a Max Range profile of 12,000 feet at 200mph TAS to 30,000 feet and at least 300 mph TAS.
2. The Engine performance of the F6F is lower than the P-47C as far as Fuel consumption at equivalent speeds and altitudes and far less than either the P-38 or P-51. Additionally the profile drag of the F6F is 8+% higher than P-47 and 54% higher than the P-51
3. The internal fuel of the F6F is 18% less (55 gallons) than the 305 gallon P-47C internal tank
4. A twenty minute fight over Berlin reduces the internal reserve of fuel for the F6F from 250 to 160 for 20minute Combat Power engine settings - assuming zero internal fuel is used during take off and assembly process (not SOP in ETO)

If you choose any other parameter or profile to make your escort case, please explain your reasons.


----------



## OldSkeptic (Oct 3, 2013)

Good summary DR, just the distance (for the fighters) is a little long. Typically they would fly out of closer airfields, eg Norwich to Berlin is only 508 miles.
Plus the bombers cruise speed was more like 180mph (for B-17s, B24s were a bit faster)

You are dead right about altitude being an important consideration, if your max economy is at a far lower height than needed for escorting then you either cruise at a non optimum height and use more fuel, or have to climb up after rendezvous cruise ... using more fuel. Plus you don't want to cross enemy territory too low as you are vulnerable to the medium AA as well as the high altitude stuff.

I just can't see how you can trick up an F-6 to do it. Maybe a Corsair with some work (and perhaps accepting CoG issues initially). Definitely a Spit (though Berlin would be the limit) and of course the later P-47s.
Those big radials really guzzled the gas.


----------



## OldSkeptic (Oct 3, 2013)

drgondog said:


> The Corsair had a dramatic drop off in power at 25000 feet, although not much worse than the P-51D, but significantly more than the P-51B with critical altitude at 29000 feet.



There was reason for that, the 51D used the -7 engine, which was equivalent to the Merlin 66, the middle altitude version, compared to the -3 on the 51B which was the high altitude one. That was (as for the LF Spits) because most combat took place at those altitudes and having that better performance at the middle altitudes (as opposed to the high ones) was more useful, especially against the 190s.


----------



## drgondog (Oct 3, 2013)

OldSkeptic said:


> There was reason for that, the 51D used the -7 engine, which was equivalent to the Merlin 66, the middle altitude version, compared to the -3 on the 51B which was the high altitude one. That was (as for the LF Spits) because most combat took place at those altitudes and having that better performance at the middle altitudes (as opposed to the high ones) was more useful, especially against the 190s.



To be totally accurate the P-51B-1 and -5 had the 1650-3 'high altitude' merlin with Critical Altitude at 29000 feet. The P-51B-7 and -10 and -15 all had the P-51D 1650-7 which had CA at 24000 feet.


----------



## wuzak (Oct 3, 2013)

Regarding the escorts forming up, could they not do that on the way to target?

In other words, their climb out is heading towards the RV point, and not orbiting the home airfield to join up with squadron mates.


----------



## davparlr (Oct 3, 2013)

prior to 1944, both the F4U and F6F will not be able to control the air above 25k. While they can fight reasonably well at bomber altitudes, 20-25k, it would be difficult for them to deal with the Luftwaffe diving through the bomber formations. The P-47D could control the high road. A better solution to the pre '44 escort problem would be to add internal fuel to the P-47, if possible, not send in F4Us and F6Fs, in my opinion.


----------



## drgondog (Oct 4, 2013)

Regarding the escorts forming up, could they not do that on the way to target?

*Practically speaking - no, for a variety of reasons. First is the necessity to count the flock with respect to disposition of spares. Second is the integrity of the Group with respect to navigating through cloud cover and bad weather. Third is entrustment of navigation to the Group leader and ensure highest probability of getting the force intact to the R/V*

In other words, their climb out is heading towards the RV point, and not orbiting the home airfield to join up with squadron mates.[/QUOTE]

The SOP for bombers was essentially the same except for the necessity of positioning the large group gaggle within a division bomber stream. The fighter group task was to be at the right place and time for the right box within a long trail. The fighter group challenge, once intact, was easier because the fighter is much faster and has the flexibility to navigate away from the stream - while checking over the tail symbols to make sure they had the 'right' group. 

Whether Fighter or bomber group, the single most important aspect of the strike was to assemble all the pieces per plan and navigate to the target.


----------



## tomo pauk (Oct 4, 2013)

Indeed, P-47 looks like a better tool for ETO, 1943-45. 
Not just that it was faster some 40-30 mph between 25 and 30 kft, it was carrying more of protected fuel. What it was lacking in 1943 were drop tanks to extend the range (though a 65 gal increase gave handsome addition to the escort radius). 8th AF tried half-full ferry tank (~100 gals) that was to be dropped when the plane is at 15000 ft, as well as with standard 75 or 110 gal drop tank. Even with a 205 gal tank, made of resinated paper, that was found as unfit for use. Such early P-47s were good for some 375 miles of escort radius. The 5th AF seem to have had more success, with 200 gal belly tank made in Brisbane, Australia, by Ford IIRC; produced from Aug 1943.
Interestingly enough, some P-47s were flown in the Aug 1943 in the UK via Island, with 2 x 150 gal drop tanks attached. With such amount of fuel (305 + 300 gals), AHT gives 425 miles of combat radius for the P-47Ds; it's 600 miles for P-47Ds that have had 370 + 300 gals.


----------



## davparlr (Oct 4, 2013)

tomo pauk said:


> Indeed, P-47 looks like a better tool for ETO, 1943-45. ....


 
I am not sure there was sufficient drive in the AAF to provide long range escorts in '42-'43. If there were, as there was in Fall of '43, I think they could have provided an extended range P-47 earlier.


----------



## Milosh (Oct 4, 2013)

Crowded skies


----------



## OldSkeptic (Oct 5, 2013)

Good one Milosh, yep there were quite a few collisions. Esecially given the (usually rotten) weather.


----------



## Milosh (Oct 5, 2013)

Theoretically the Tempest could have provided long range escort when fitted with 90gal d/ts but would have the same problem regarding altitude as did the F6F and F4U.


----------



## stona (Oct 5, 2013)

That assembly diagram is scary. It doesn't represent a very large area for a lot of aircraft. For the non-Brits, from Leicester to Norwich, as the crow flies, is about 100 miles.
Cheers
Steve


----------



## drgondog (Oct 5, 2013)

In spring 1945, 2000+ bombers and 1000+ US fighters were overlapping their assemblies. O March 24, combine That number with the 500+ C-47/C-46 plus gliders for just the US Airborne troops headed for the Rhine crossing.


----------



## GrauGeist (Oct 5, 2013)

A friend of mine, who was a B-24 pilot based out of England, said assembly was often scarier than actually being over Germany.

Climbing into the overcast, he would occasionally see shadows pass right overhead or directly in front of him (he said he lost count ofmthe near misses they had) and once in a while, there would be a bright flash briefly illuminating the clouds that was the result of a mid-air collision.

Once he cleared the overcast, the spectacle of all of the bombers assembling was almost beyond description.

Definately not a job I would have preferred...


----------



## tomo pauk (Oct 6, 2013)

Milosh said:


> Theoretically the Tempest could have provided long range escort when fitted with 90gal d/ts but would have the same problem regarding altitude as did the F6F and F4U.



I'd say that opposite was true - Tempest was capable for 420+ mph at 25000 ft (20-40 mph faster than F4U and F6F), but the fuel tankage is too low for a long range job. Tempest V ADS gives range of 680 miles (internal fuel only; most economical cruise - 295 mph), after warming up, take off and climb (uses ~ 40 imp gals of internal fuel). So it's some 120 imp gals for those 680 miles left (5.66 milef for gallon) . For every 5 minutes on combat power, 105 miles are to be subtracted from those 680 mi. 15 minutes of combat - 315 miles less, or total of 365 miles to return home and land immediately. Here.
British were modifying the Tempest, adding the 30 imp gal fuel tank in the right wing (only one wing LE tank was present in 1944, I'm not sure how many were actually modified before the war ended). With that fuel, the range was increased by 150-260 miles (depending whether and how big the DTs are carried). 150 gals should yield 850 miles; subtracted by 315 miles it should give 'return radius' of 535 miles.


----------



## Aozora (Oct 7, 2013)

stona said:


> That assembly diagram is scary. It doesn't represent a very large area for a lot of aircraft. For the non-Brits, from Leicester to Norwich, as the crow flies, is about 100 miles.
> Cheers
> Steve



Fortunately its all flat! I've been told that molehills are the highest natural feature...although it is rumoured that some trees do exist.

The 8th AF used "assembly ships" brightly painted, war weary (usually) B-24s as an aid to getting the various Bomb Groups formed up


----------



## davparlr (Oct 7, 2013)

Super cool!


----------



## GrauGeist (Oct 7, 2013)

Jimmy Stewert flew a Judas Goat with his group across the channel on D-Day...how's that for gutsy?


----------



## Neil Stirling (Oct 7, 2013)

Americas Hundred Thousand page 600.

P51 D 
Fuel 269 US gallons internal + 2 75 gallon drop tanks = Combat Radius 700miles.

Conditions:-
Warm up and take off = 5 minutes normal rated power.
Climb to 25,000ft normal rated power no distance included.
Cruise out at 25,000ft at 210. I.A.S (about 315mph)
Drop tanks.
Cruise back at 25,000ft at 210mph I.A.S
30 minutes reserve at minimum cruise.
Combat 5 minutes Wep and 15 minutes Military power.
Takes no account for decreased fuel consumption during decent.
No allowance is made for formation flight or evasive action other than 20 minutes combat.

F4U-1 Corsair (no wing tanks) I.A.W. Pilots Manual page 50 and 63

Total fuel including 154 gallon drop tank 391 gallons.

Warm up and take off 18 gallons
Climb to 25,000ft 64 gallons ( difference split between Combat climb and Ferry climb)
Combat 5 minutes wep and 15 minutes military power 91 gallons
30 minutes reserve at minimum cruise = 21 gallons

Total = 194 gallons.
391-194 = 197

197 gallons at 315mph at max cruise at 26,000ft (82 gallons per hour) 197/82 = 2.4
2.4 * 315mph = 756
756/2 = 378 miles.

F4U-1 combat radius = 378 miles. 

Or in other words 54% of a P51-D.

Neil.


----------



## syscom3 (Oct 7, 2013)

GrauGeist said:


> Once he cleared the overcast, the spectacle of all of the bombers assembling was almost beyond description.



I heard the same thing too from a B17 tail gunner.


----------



## bob44 (Oct 7, 2013)

Did not know about those high visible painted bombers. Very cool.
Thanks for the information from Americas Hundred Thousand.


----------



## model299 (Oct 8, 2013)

In the Pacific Theater, it was common practice to assign one B-29 to the escort fighters to form up on, and then act as group navigator for the fighters to the target. Upon reaching Japan, the B-29 so assigned would orbit at a designated location until the fighters were finished with the mission. it would then "escort the escorts" back to the Iwo Jima base. That way, the fighter pilots didn't have to deal with long distance overwater navigation.


----------



## Timppa (Oct 8, 2013)

drgondog said:


> In spring 1945, 2000+ bombers and 1000+ US fighters were overlapping their assemblies.



I believe that all of the 1000+ did not assemble with the bombers (if any), as they had their relay points along the route.
Also the bomber stream was stretched, so I would guess that they did not all took off at the same time also.
Arthur Price in his book gave a very schematic picture of the fighter relays of the 11 Jan 1944 mission, Halberstadt/Brunswick/Oschersleben -raid. Total of 14 FG's, but only one (P-51's) over the target.


----------



## Njaco (Oct 8, 2013)

All that assembly - in poor weather - just to try to get into this formation. Amazing...

.


----------



## fubar57 (Oct 8, 2013)

Aozora said:


> Fortunately its all flat! I've been told that molehills are the highest natural feature...although it is rumoured that some trees do exist.
> 
> The 8th AF used "assembly ships" brightly painted, war weary (usually) B-24s as an aid to getting the various Bomb Groups formed up



First time I've seen a photo of the second one down from the top. P.R.U. Blue?

Geo


----------



## GregP (Oct 8, 2013)

Fish flopping in a mud puddle, Drgondog, that is YOU buddy. And not a very nice one ...

At least you weren't required to PERFORM the duty in the event. I'd have figured a way, or at least tried my best. Perhaps one item you may have overlooked ... if you send normal escorts until they are required to turn back and then send later planes that are configured for range but don't have to fight their way in, THEY could catch the formation, drop the extra longs range tanks and then continue escort. The Luftwaffe may not have had the planes to attack both bomber streams and a stream of fighters that could drop tanks and kill them. If they did at first, they would not for long. Same result after a short period of intense fighting. You nmight remeber the Hellcat had a service ceiling abit ofer 37,000 feet. Enough easily for Europe.

As I stated before, not optimum, but possible. You sound like the fish out of water to me. I work on these planes today. Do you?

Why not stop being insulting and discuss? Or are you so egotistical you simply can't discuss nicely? I will if YOU will, but it takes two twits to do it. Wanna' BE one of them? Or continue being an insulting guy?

I know the answer but had to try. I'll still welcome you if you manage to visit the Planes of Fame. If not, I suppose we both will not lose any sleep over it.


----------



## GrauGeist (Oct 9, 2013)

GregP said:


> I work on these planes today. Do you?


Seriously, Greg...that means nothing in this discussion.

I have worked on a B-17F, Bf109E and several other aircraft over my lifetime and it doesn't qualify me for anything. I have shook hands and held conversations with Space Shuttle Astronauts and that gives me zero qualification. Zero.

Dragndog, shortround and several other people have presented hard statistics and facts regarding Hellcat operations proving it was not suited for long-range ETO ops and yet you insist on pressing the issue. The bottom line is that a "what-if" for the Hellcat just simply won't work.

What if the Luftwaffe took a Bf109 loaded with external tanks and towed a winged fual-tank behind it and flew to New York...it could be done, right? And when it got there, the pilot flipped off the statue of Liberty...what then?

This thread is about bomber escort logistics, not fanciful one-way missions with improbable aircraft.


----------



## GregP (Oct 9, 2013)

No it doesn't mean I fly them, but it DOES mean I talk with the pilots who DO. I Have ASKED ... and I BELIEVE them not the dog.

You believe whatever you want, makes no difference to me. I really don't care since it wasn't a scenario that played out for real.

The point is ... it COULD have and this guy just can't see it. Well, we can't all Narffle the Garthog, can we? All is well and that's OK with me. 

By the way we flew a Hellcat 1,500 miles nonstop for an airshow ... so I KNOW it can be done. Sorry, but the facts speak for themselves, and it really doesn't make sense to me to be acrimonious about it 70+ years later. If it does to you, we live in different worlds, philosphically. That's OK, too.

I'm not the fish flopping in the mud puddle, Drgondog is. My objection is the venom, not the facts. I already KNOW them.

Naval reserves are WAY more than for land planes. READ about it. If flying a land-based mission, the reserves would be wildly different. The base doesn't move around as it does in the ocean, as I said before. Naval flight planning is MUCH different from land-based flight planning.

But, work it out for yourself. Assume you HAVE to make it succeed or lose the war. How would you DO it? Forget saying no, work it out.

Then let it go, it never happened in real life so ONE of us is wrong. Which one is singularly unimportant ... the war is well over and we KNOW who won.

This is a what-if only. And it CAN be done but is difficult and unconventional and there was no reason to DO it, as with most what-ifs.

Since this one got so acrimonious, I'll not try another what-if. I said that before but slipped ... not again.


----------



## GrauGeist (Oct 9, 2013)

Sorry Greg, Dragndog and the others ALL presented sound hard facts that prove your scenario wouldn't work.

*MAYBE* if the ship took off immediately with no assembly, stripped of all hardware and loaded to the gills with fuel AND praying to God it didn't encounter eny Luftwaffe elements or bad weather...then *maybe* it could be done..hardly a comforting image.

Looking at the charts and data presented, it's a no brainer. So why argue over such a moot point when the factory and military data indicate otherwise?



> By the way we flew a Hellcat 1,500 miles nonstop for an airshow ... so I KNOW it can be done. Sorry, but the facts speak for themselves, and it really doesn't make sense to me to be acrimonious about it 70+ years later.


So I'm assuming then, "_you_" took off and climbed to the rally point while the other hellcats formed up, then cimbed to your assigned combat altitude and then had to "jink" over the bomber formations along the way...tell me, how was your war loadout? Full belts of MG ammo adding to the weight and what was the external fuel supplied? 

You seem to keep falling back on this "flipflop" term for some reason, when everyone is presenting ACTUAL combat rated stats, not a happy little cruise across peaceful skies under conditions that weren't even though about back then.

B-17s were ferried across the Atlantic and the Pacific during the war, but were they carrying a bombload, armed or fully crewed? No...and why was that? Because of this thing called range.

So could a Hellcat follow the route of the historic escorts? Yes.

Could it have done so in a wartime escort capacity? No.

Pure and simple.


----------



## GregP (Oct 9, 2013)

It's OK, assume whatever you want. We took off and flew to a destination ... 1,500 miles away. It is possible.

Even if you think it isn't, you could at LEAST escort the bombers a good way there. We only disagee on the distance, and that would be stettled really quickly. Maybe one or two missions. No possibility it couldn't be determined.

One of us would be wrong. I think it is you and you think it is me.

So, we should discuss over a beer and not be impolite in here about it. When you visit, I'll buy.

Not so pure and simple.

If you DO visit, PM me. This is tedious.


----------



## wuzak (Oct 9, 2013)

GregP said:


> We took off and flew to a destination ... 1,500 miles away. It is possible.



Greg, would be helpful to know the parameters of that flight.

At what speed and altitude was it flying, and how much fuel was it carrying?


----------



## wuzak (Oct 9, 2013)

GregP said:


> Even if you think it isn't, you could at LEAST escort the bombers a good way there. We only disagee on the distance, and that would be stettled really quickly. Maybe one or two missions. No possibility it couldn't be determined.



Before the P-51B, the USAAF had aircraft that could escort the bombers "a good way there". The problem was that it wasn't far enough. Bombers were mauled once they were out of escort range.


----------



## OldSkeptic (Oct 9, 2013)

Sorry Greg, I have agreed with you on many other things before. But I just can't see it with the Hellcat. Plus, even if somehow you could do it, it just didn't have the performance to be competitive in the late 43 to mid 44 period. The 109Gs and late 190As, let alone the 190Ds would have ran rings around it.

The Corsair is theoretically possible, but would require significant re-engineering to fit enough fuel into it. And, for *that *task, would not have been any better (and in some ways quite a lot worse) than a late model P-47, let alone a P-51.

There were 3 possibilities of planes that not only could have the range but have the performance to both survive and do the job in that environment:

Early-mid 43: LR Spit VIII, MR P-47 and a LR P-38.
Late 43 onwards: P-51 (B/C/D plus it was a VLR), Late model LR P-47s. LR (even VLR with the late models) P-38s and a LR Spit VIII and then XIV (both Spit versions being technically straightforward).

The Spits were out because of internal RAF politics (despite tremendous USAAF pressure to provide it), the other possibility the P-38 was out because of various technical issues and that miserable mach limit (which as it got faster it got closer to in level flight, let alone diving at those altitudes), therefore all the US really had at the beginning that was really effective was the MR (Medium Range) P-47s of the time. Hence the slaughtering of the bombers.

The Mustang was so good for the job, not just because of its range but its performance was more than enough to be competitive (in fact it was markedly superior in many flight regimes). The LR P-47s weakness was their also poor mach limit (though not nearly as bad as the P-38), it's weight (not helped by the huge fuel consumption requiring lots of fuel for the range required) which, though it was a very hot ship at altitude, severely impaired its climbing performance (not just in speed but in fuel consumption). It did help its dive of course, but that's where its mach limit really started to bite. Thus it was sub-optimal as a LR/VLR escort and dropped as such as soon as there were enough P-51s.

The P-51 started out as a LR fighter (even without the rear tank, when that was added it was a VLR), all it needed was high altitude performance, amply given by the Merlin.

For *that * role there were no USN planes with the range and performance required *at that time* to do *that *job and survive in that incredibly harsh environment.

To put the Hellcat into that you would have to effectively increase its combat range (for that role) by 50% or more .... and increase its performance by at least 20-30mph ... and increase its high altitude performance by about 10,000ft.

Doing all that means you are really looking at a VLR version (if possible) of a Bearcat, a much later design.

The Mustang was heavy by ETO standards, it got away with that by clever aerodynamics, USN fighters were even heavier (as all carrier planes are), therefore to create a plane with all the attributes required for that ETO role means pulling a big technical rabbit out of the hat.

_Edited to add: Thinking about it,the USAAF wasted too much time trying to get Portal to release a LR Spit. They should have just gone over his head, got all the Spit VIIIs allocated to the USAAF (easily done, just threaten to hold up Lend Lease until they do) and do their own conversions and just completely ignored the RAF._


----------



## wuzak (Oct 9, 2013)

I suppose you could launch F6Fs off carriers in the North Sea for the final leg, but how many carriers would you need? And how many were available?

Or, have the carriers as a waypoint - land, refuel and relaunch. But that takes time, and to service the numbers of aircraft required would still require many carriers.


----------



## drgondog (Oct 9, 2013)

wuzak said:


> I suppose you could launch F6Fs off carriers in the North Sea for the final leg, but how many carriers would you need? And how many were available?
> 
> Or, have the carriers as a waypoint - land, refuel and relaunch. But that takes time, and to service the numbers of aircraft required would still require many carriers.



And how vulnerable to subs and night attacks?


----------



## drgondog (Oct 9, 2013)

For Greg to get back in the conversation he has to show what kind of fuel consumption the F6F-3/5 would have at 300 mph TAS at 30,000 feet - when he can only hint at 12,000 feet and 200mph.


----------



## wuzak (Oct 9, 2013)

drgondog said:


> And how vulnerable to subs and night attacks?



Yes, there is that!


----------



## tomo pauk (Oct 16, 2013)

Let's see If I can contribute something here 

Looking at aircraft data sheets at wwiiaircraftperformance.com, we can see that planes are using part of internal fuel in order to take off and climb into necessary altitude. Eg. Spitfire VIII/IX will use 23-26 imp gals to take off and climb to 20000 ft, depending how big a drop tank they are lugging around. That amount of fuel is then deduced from internal tankage, and resulting range is stated after that - Spit HF.IX will have the range of 434 miles at most economical cruise, or 252 miles at maximum weak mixture regime. Mileage is some 6.9 mpg, or 4 mpg. The plane will, of course, fight, and the extra consumption makes a dent at the remainder of the fuel - 15 min at combat power will decrease the range to 188 miles (m.e.c. cruise) or 108 miles (m.w.m cruise). 
Spit HF.VIII will do much better, 660 or 390 miles of range, mpg is either 6.8 or 4 mpg, depending whether its the m.e.c. of m.w.m.cruise. After 15 min at combat power, the range is either 420 or 261 miles. We might call that range as 'return range' - the fighter arrives to the fight using drop tanks, and will fight on what is remained in the internal tanks.

However, that procedure (TO and climb on internal fuel always, drop/rear tanks notwithstanding) is at the contrary to what manual (for Spit IX, XVI;dated Sept 1946) says:






In other words, switching at 2000 ft to either rear tanks (if present) or drop tanks. That procedure saves how much - 15-20 gals? - during the climb? It then translates into between 60 miles (worst case) and almost 140 miles (best case). Or, the 'return range' should be increased up to, at m.e.c. power, 327 miles (Spit IX) or 559 miles (Spit VIII). On maximum weak mixture, it's 168 (Spit IX) or 320 miles (Spit IX).
Spit HF.VIII cruised at 220 mph (most economic cruise) or 322 mp/h (maximum weak mixture) at 20000 ft. Obviously, the plane will cruise back at m.w.m mixture at least half of the way, until rendezvous with friendly fighters, for a realistic 'return range' of some 250 (Mk.IX) or 450 miles (Mk.VIII).

I'm open to corrections.


----------



## Shortround6 (Oct 16, 2013)

I think you have it right. There is no _need_ to climb to 20,000ft on internal (main tank) fuel. There IS a safety need to take-off using the main tank/s and NOT switch until enough height had been gained to allow for the engine cutting out when the the tanks are switched. What the safe height is, 2,000ft, 5,000ft I don't know but 20,000ft sure seems excessive. 
But do not disregard the time/fuel needed to form up either even if it is coming from drop tanks.


----------

