F6F Hellcat vs. P-47 Thunderbolt

[GregP]

Hi CV-6,

How can you say that? In a one-on-one, you are, almost by definition, in a dogfight. There is almost no other one-on-one fight possible except maybe a boom-and-zoom. And if THAT is one-on-one, it isn't too hard to keep track of the boom guy. In any one-on-one I'd take the Hellcat any day of the week.

At high altitudes, it would switch to the P-47.

Biff, please explain something. It may be different today but, in WWII, the wingman stayed with his leader. So in a 2-on-1 one, the advantage would not be anywhere near as pronounced as if the two split up and attacked separately against the one. What do you say? I think there would be no great advantage to the two guys if they stayed welded in combat formation since two planes are not as maneuverable as one.

 

[USS Enterprise CV-6]

Hi CV-6,

How can you say that? In a one-on-one, you are, almost by definition, in a dogfight. There is almost no other one-on-one fight possible except maybe a boom-and-zoom. And if THAT is one-on-one, it isn't too hard to keep track of the boom guy. In any one-on-one I'd take the Hellcat any day of the week.

At high altitudes, it would switch to the P-47.

Biff, please explain something. It may be different today but, in WWII, the wingman stayed with his leader. So in a 2-on-1 one, the advantage would not be anywhere near as pronounced as if the two split up and attacked separately against the one. What do you say? I think there would be no great advantage to the two guys if they stayed welded in combat formation since two planes are not as maneuverable as one.

But a head on attack isn't a dogfight, is it? And BTW you are the first person to do CV-6 THANK YOU

 

[GregP]

Well CV-6, a head-on attack isn't a dogfight and usually may not result in a kill either. Perhaps there may be some first-pass victories, true, particularly if one didn't see the other ... but I thought it was to be a one-on-one FIGHT, not an ambush.

If they aren't first-pass victories, there is nothing left but a dogfight. If one or the other runs, it isn't exactly a fight. One MIGHT run if he was low on fuel, wounded, or otherwise mechanically or physically handicapped, but that isn't exactly the scenario I envisioned to start with.

I figured a one-on-one fight was two working aircraft flown by competent pilots meeting at the same altitude with fuel and ammunition to use. In other words, equal starting positions and have at it.

Other scenarios are meant to favor one or the other from the outset.

 

[USS Enterprise CV-6]

Well CV-6, a head-on attack isn't a dogfight and usually may not result in a kill either. Perhaps there may be some first-pass victories, true, particularly if one didn't see the other ... but I thought it was to be a one-on-one FIGHT, not an ambush.

If they aren't first-pass victories, there is nothing left but a dogfight. If one or the other runs, it isn't exactly a fight. One MIGHT run if he was low on fuel, wounded, or otherwise mechanically or physically handicapped, but that isn't exactly the scenario I envisioned to start with.

I figured a one-on-one fight was two working aircraft flown by competent pilots meeting at the same altitude with fuel and ammunition to use. In other words, equal starting positions and have at it.

Other scenarios are meant to favor one or the other from the outset.

Good point. At high alltitudes, P-47, mid to low alltitudes, F6F. Both were very tough and had very good firepower.

 

[GregP]

We agree there. Cheers.

 

[BiffF15]

Hi CV-6,

How can you say that? In a one-on-one, you are, almost by definition, in a dogfight. There is almost no other one-on-one fight possible except maybe a boom-and-zoom. And if THAT is one-on-one, it isn't too hard to keep track of the boom guy. In any one-on-one I'd take the Hellcat any day of the week.

At high altitudes, it would switch to the P-47.

Biff, please explain something. It may be different today but, in WWII, the wingman stayed with his leader. So in a 2-on-1 one, the advantage would not be anywhere near as pronounced as if the two split up and attacked separately against the one. What do you say? I think there would be no great advantage to the two guys if they stayed welded in combat formation since two planes are not as maneuverable as one.

GregP,
From what I have read, watched, etc. I would say you are on the right track. What I mean by that is during the early part of the war, "Allied" forces tended to use the either welded wingman formation (1 flight lead and 2 wingman) or a 2 ship that was pretty strictly defined by their position (flight lead equals shooter), (wingman equals check six guy / lead sponge / if I run out of ammo it's your turn). Hard to maneuver, hard to defend the wingmen, but totally supporting the flight lead in his quest for kills. It is my understanding that the Germans introduced the 2 4 ships (rotta and schwarm sp?) with the idea of mutual support. Or, one flight or flight member can or will maneuver to support, defend or attack to protect the flight. They also had the benefit of being at war for several years before "we" got into it. This basically means enough distance between the lead and his wingman that they can maneuver without fear of collision, and the wingman has a long enough leash that he can maneuver to stay in position (able to support the flight lead should his weapons fail or he become defensive), and or shoot should the opportunity arise. The Allied fighters eventually adopted that mentality and it still exists today to varying degrees. Another example of it is the Thach Weave (rudimentary by todays standards but "mutual support" it is).

To more specifically answer the question of 2 on 1 it would depend on the time frame of the war, and the skill levels of the pilots. Early on, the advantage would not be as pronounced as later in the war. Early on the wingman was stuck in a welded formation, flying fairly close to his leader. Later the formation was more fluid (longer leash for the wingy), and therefor more maneuverable. Later in the war if it was a flight lead and a young guy, results would probably be similar to two experienced guys early in the war (training improves the breed). Turn the tables and make it two experienced guys later in the war and the odds would go up significantly (in my opinion from what I have read and seen during my time in fighters).

I've enjoyed watching this conversation from afar for the most part. It is, as has been stated previously, what I would call a "it depends" situation. I could probably come up with several scenarios in which one fighter would do better than the other (same goes for the Spit versus X in the other thread). How far away from their launch base are they going to fight, does the weather force the fight to be high or low, is one guy fighting over his own country, is one aircraft war weary and the other fairly new, etc. I really believe that it will eventually boil down to the guy that wins will be better at using his weapon than the other guy. These planes are all fairly close. Yes, some are faster, climb better, turn better, have more guns / cannons, longer range, better vis, etc. If I were flying the Thunderbolt I would push for a high altitude fight and maneuver to get on my adversaries tail quickly. If it looked like I might be losing the offensive / going defensive then I would leave the fight, climb to altitude again, and use the zoom and boom. If I were flying the Hellcat, then I would push for a lower altitude turning fight which played to the strengths of my ride. It is my opine that a guy could win in either, he would just have to fight smart (use his strengths against his enemies weakness and not let that same thing happen to him). If maneuvering was the end all be all then the IJN and Mitsu would not have been looking to create an A7M type of aircraft.

Just my dos pennies...

Cheers,
Biff

 

[GregP]

Thanks for the informative post, Biff.

It's always nice to hear from a guy who has been in the seat doing it.

 

[AlfaKiloSierra]

I'll prefer the P-47 for its speed and rate of climb.

The F6F-3 and -5 utilize a two-stage three-speed supercharger. For each stage of the supercharger there is a critical altitude, above which the supercharger cannot compress air enough to maintain the maximum allowable boost (manifold pressure), and below which the throttle must be partially closed in order to prevent engine knocking (the condition where the fuel-air mixture detonates instead of burning normally). Both conditions significantly reduce the power of the engine, therefore the F6Fs perform best at the three critical altitudes of the supercharger. Engine power is the highest at the lowest supercharger critical altitude, because a supercharger speed setting with a higher rpm takes more power from the engine.

All variants of the P-47 have a turbocharger with wastegate. Below the critical altitude, the wastegate (controlled by the pilot on all variants except the N-25, which has an automatic one) vents exhaust upstream of the turbocharger, also preventing engine knocking. The P-47, if not considering intake ram effect, has constant power up to its critical altitude.

The three critical altitudes of the F6F-5 are 2500ft, 18600ft and 23800ft in level flight, this is slightly higher than that in steady climb or static because of intake ram effect. It reaches 321mph, 370mph and 376mph at altitude, respectively.
http://www.wwiiaircraftperformance.org/f6f/72731-level.jpg

The P-47D, razorback, 56" boost, 2700rpm reaches 333mph at sea level and gets progressively faster as altitude increases.
P-47 Performance Tests (see MEMORANDUM REPORT ON P-47D-10 Airplane, AAF No. 43-75035)

The three critical altitudes of the F6F-5 are 1200ft, 15400ft and 20400ft in steady climb. The rate of climb at altitude is 2910ft/min, 2510ft/min and 2180ft/min respectively.
http://www.wwiiaircraftperformance.org/f6f/72731-climb.jpg

The P-47D, razorback, 56" boost (about 2200-2300hp, varies), if having a Hamilton Standard propeller, stays above 3000ft/min until 12000ft, dropping off to about 2700ft/min at 15400ft.
http://www.wwiiaircraftperformance.org/p-47/P-47D_43-75035_Eng-47-1714-A.pdf (page 5)

With the comparison above, the P-47D outclimbs and outruns the F6F-5 at all altitudes. Notice that this is a 56" boost P-47, which is far worse than a 70"boost P-47D near the end of the war. A P-47D with 70" boost, 2700rpm and improved water injection significantly outruns and outclimbs the P-47D with 56" boost, especially at lower altitudes.

 

[AlfaKiloSierra]

Interestingly the Corsair was more accurate at very high angle dive bombing than the SBD.

Do you have a source for that claim? Please see my post above regarding the evaluation of such a claim.

The facts are that the Corsair was used as a high angle divebomber and was effective in WW2 and the Corsair was judged as a better carrier fighter and fighter bomber on May 16, 1944 than the Hellcat by a USN evaluation board.

And in May of 1946, two years later and with the benefit of 20/20 hindsight and mountains of actual data, the USN judged that that the Hellcat had a "considerable advantage over the F4U when flown under the same conditions" and was actually superior in combat. 26% of Hellcats that suffered combat damage were destroyed while 41% of Corsairs met that fate.

The F6F appears to have had considerable advantage over the F4U when flown under the same
conditions. Receiving about the same number of hits per sortie in comparable operations, the
F6F had a far lower rate of loss per plane hit.

Page 79, Note (e) to Table 29 of Naval Aviation Combat Statistics, WWII

Thus comparisons are valid between the carrier F6F and F4U totals because they generally operated from the same ships during the same periods.
...
Certain tentative conclusions may be reached from these two tables:

(a) The F6F was slightly superior to the F4U in combat, apparently chiefly because of its greater ability to survive damage.

Page 58 and Table 19:

I for one would have rather gone into combat with a Hellcat as its performance was still superior to its adversaries and it didn't have the glass jaw, Achilles heel or however you would like to characterize the Corsair's far greater vulnerability.

The Corsair koolaid is powerful stuff. I have no doubt that had the USN's studies established that the Hellcat was 57% more likely to be brought down than the Corsair after suffering battle damage "when flown under the same conditions," that your posts would be peppered with that fact in game, set, match, end of story fashion.

There are plenty of performance charts on wwiiaircraftperformance.org, and an F4U-1 in 1944 easily outruns and outclimbs the F6F-5 at all altitudes.

 

[AlfaKiloSierra]

Agreed, but what is this I hear about the P-47 being a "great climber?" One of my favorite anecdotes about the P-47 comes from Hub Zemeke, after he was congratulated on proving that the P-47 could outdive a 109. He said, "By god, it ought to dive- it certainly won't climb!" (I have seen this quote attributed to Donald J.M. Blakeslee as well.) In fact, the poor climb rate of the P-47 is the one thing I hear about the most, right behind it's incredible ruggedness. The data on wikipedia shows the F6F has a slight advantage in climb rate (3,500ft/s to 3,125), not a disadvantage.

Sadly, I almost never see roll rate data, anywhere, but the impressive roll rate of the P-47 is well known, so I'll assume it had the advantage there. The P-47 was faster and rolled better, the F6F rolled well (but not as good as the Jug) and turned rather better (wing loading of 37.7lbs/square foot to 58.3).

These ships seem very similar in performance. It would seem that it comes down to what you consider more important, turn rate or roll rate. I'd say roll rate, personally, but it's worth considering that the F6F was a good roller and had good turn; it's just that the P-47 was an exceptional roller.

I would love, with all my soul, to find data that gives the rate of roll in degrees/sec for these ships.

Climb rate. Wikipedia claimed a climb rate without giving an altitude, making the data useless. A report (which you can see in one of my posts on page 10 of this thread) shows the F6F-5 does not reach such a climb rate at any altitude.

Roll rate. https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19930090943.pdf page 45. The P-47 out-rolls the F6F at all indicated airspeeds.

 

[AlfaKiloSierra]

As a fighter, just about everything you read says the Jug was at its best at 30,000 feet.

NO. As the war progresses, the P-47 engine could accept higher and higher manifold pressure, by the end of the war it could accept 70 inHg, and the speed was maximized at 23200ft and climb rate was maximized at 10000ft. P 47D Performance Test Using 44-1 Fuel

 

[Shortround6]

The F6F-3 and -5 utilize a two-stage three-speed supercharger

technically the F6F (and the F4U) used a single speed engine supercharger and a two speed with neutral auxiliary supercharger, some may consider that as three speeds.

At low altitudes the auxiliary supercharger was in neutral (no power going to it) and all boost was supplied by the engine supercharger. When the engine supercharger started to run out of "puff" (technical term the aux supercharger was clutched at low gear and when that combination ran out of "puff" the aux supercharger was shifted to high gear.

In all cases the engine supercharger ran at the same speed.

the result was as you describe.

 

[CORSNING]

Apples to oranges. The P-47Ds reach 70"Hg boost giving it speeds at higher
altitudes that the F6F could not hope to reach. The F6F was designed to come
off the deck of a constantly moving vessel, which it did in spades at a time it
was needed most.
It would be interesting to hear what the USN VF-9 pilots aboard the USS Essex
would say if they had received P-47Cs on 16 January 1943 instead of F6F-3s...?

 

[AlfaKiloSierra]

Apples to oranges. The P-47Ds reach 70"Hg boost giving it speeds at higher
altitudes that the F6F could not hope to reach. The F6F was designed to come
off the deck of a constantly moving vessel, which it did in spades at a time it
was needed most.
It would be interesting to hear what the USN VF-9 pilots aboard the USS Essex
would say if they had received P-47Cs on 16 January 1943 instead of F6F-3s...?

The maximum allowable boost doesn't affect performance above critical altitude. A 70" boost P-47 means the P-47's engine can run at 70" boost, but doesn't mean that it always runs at 70". It allows a significant increase in power if the turbocharger can give 70" boost into the engine at that altitude. In level flight at maximum speed, the turbocharger maintains 56" boost up to 31000ft, and in optimal climb, the turbocharger maintains 56" boost only up to 25000ft. Therefore above 31000ft, the 70" P-47 performs exactly the same as a 56" P-47. 70" boost improves performance at low altitude drastically. With 56" boost, as I have demonstrated, the P-47D outruns and outclimbs the F6F-5 at all altitudes, provided that the P-47D has the Hamilton Standard propeller.

 

[CORSNING]

My point was the P-47 could not operate as well off a carrier
and that is what the USN needed.

 

[IdahoRenegade]

Different tools for different jobs. The Hellcat didn't have the speed, rate of climb or high altitude performance to do long range bomber escort and take on the BFs and FWs at 30,000 ft over Europe. And the '47 couldn't land on a carrier. Both excelled where they were used-but were hardly comparable or interchangeable.

How did the range compare between the two?

 

[AlfaKiloSierra]

Different tools for different jobs. The Hellcat didn't have the speed, rate of climb or high altitude performance to do long range bomber escort and take on the BFs and FWs at 30,000 ft over Europe. And the '47 couldn't land on a carrier. Both excelled where they were used-but were hardly comparable or interchangeable.

How did the range compare between the two?

Several reports on wwiiaircraftperformance.org didn't agree with each other, but F6F mostly had a range around 1200mi, some above and some below by as much as 200mi, all in clean condition with droptanks. P-47D with droptanks has a combat radius of 600mi and the P-47M which couldn't carry droptanks had a combat radius of 400mi consistently on that website. Nobody offered P-47 range or F6F combat radius so oof

 

[CORSNING]

http://www.alternatewars.com/SAC/F6F-5N_Hellcat_ACP_-_1_July_1944.pdf

Keep in mind that the figures on these graphs and charts are for an F6F-5N.
This model had the extra weight and drag of the radar dome on its right
wing. Also notice the maximum power used on this report was 2,135 hp.
from S.L. to 12,400 ft. The R-2800-10W was capable of 2,250/S.L @ 58"
2,135 hp./12,400 ft. @ 60" Hg and 1,975 hp./16,900 ft. @ 60" Hg boost.


http://www.wwiiaircraftperformance.org/f6f/hellcat-II-ads-a.jpg

 

[IdahoRenegade]

Several reports on wwiiaircraftperformance.org didn't agree with each other, but F6F mostly had a range around 1200mi, some above and some below by as much as 200mi, all in clean condition with droptanks. P-47D with droptanks has a combat radius of 600mi and the P-47M which couldn't carry droptanks had a combat radius of 400mi consistently on that website. Nobody offered P-47 range or F6F combat radius so oof

To me it's really impressive that they were able to get that kind of range out of the Hellcat! Lot of fuel weight to haul off the deck of a carrier.

 

[AlfaKiloSierra]

The most unromantic successful plane of the war versus the most polarizing.

No one talks about the F6F but it (IIRC) killed more enemy planes than any other American fighter.

People eaither love the P-47 (like me) gushing about its toughness, firepower, number of kills, number of sorties (most in Europe), realiability (mission ready %), and dive speed. Or they hate it because it was no dogfighter, turning like a city bus and only fit for the climb and dive.

The P-47 killed more planes (I think) than the P-51 but was overshadowed by it. The F6F was similarly overshadowed by the F4U Corsair though it definitely killed far more enemy aircraft, though many would say this would not have been the case that the F4U not been only barely carrier capable due to dangerous landing qualities.

The F6F is not overshadowed by the F4U, if not the opposite. The F6F is remembered as the plane that defeated the Zero (the P-38 as well), and the F4U is remembered as a fighter-bomber if known at all.