1941: the best case for 350+ mph CV fighters?

[pinsog]

I wondered about F4F with turbo myself since the P43 was about the same size and shape and it had a turbo

 

[tomo pauk]

The F4F was bigger, wing area bigger by almost 20%. That will shave some speed from what P-43 was making, but will make wing loading favorable, same with low speed handling vs. P-43.

 

[wuzak]

WUZAK, as I said earlier, they would have to ditch the F4F-3 and only work on the Skyrocket. Unlike the Hellcat and Corsair, the technology was there in 1939, as proved by the P43. Not completely perfected, but there.

The YP-43 aircraft were ordered in March 1939. The first delivery was in September 1940.

Shortround, I would definitely do the version you are showing with the longer nose and not the 1st version, but using P&W 1830's instead. Even if you ditch the turbos, you are still getting Hellcat performance. It is 35 mph faster than a Wildcat or Zero at sea level and 20 mph faster than a Spitfire MkII at sea level. It's 20 mph faster than a Zero at any altitude.

Of course the Spitfire II had an engine rated for a higher altitude than did the XF5F, and only one supercharger speed, so it suffered down low. But the Spitfire II was in full production, had armour, self sealing tanks, 2 x 20mm cannon and 4 x 0.303"mgs. The XF5F had none of that.

Will the turbo and intercooler fit in the back of the lengthened nacelles? Where was the intercooler on a P43? The fit a turbocharged 1830 in a P43 in 1939 in the same sized package as an F4F-3 with a 20-25 mph speed advantage over a Wildcat at any altitude.

Maybe you should be arguing for a navalised P-43?

Good question on where the intercooler was on the Lancer.

 

[tomo pauk]

...
Good question on where the intercooler was on the Lancer.

The manual for the P-43 states that intercooler is located prior the carburetor, job being the removal of excess heat from the compressed air.

 

[wuzak]

The manual for the P-43 states that intercooler is located prior the carburetor, job being the removal of excess heat from the compressed air.

But where in the airframe?

Is the turbo to the rear?

 

[tomo pauk]

I've had the picture of the plumbing of P-43 turbo system, unfortunately can't find it today.
The turbo was at the rear. (Pictures) Single waste gate, the most visible, longitudinal duct is for exhaust gasses.

 

[wuzak]

I've had the picture of the plumbing of P-43 turbo system, unfortunately can't find it today.
The turbo was at the rear. (Pictures) Single waste gate, the most visible, longitudinal duct is for exhaust gasses.

Thanks Tomo.

I am having a hard time seeing where air would enter to cool an intercooler.

 

[Shortround6]

Here is a website with many good pictures of the P-43:
Forums / USAAF / USN Library / Republic P-43 Lancer - Axis and Allies Paintworks

Please note there are several pictures of the inside of the rear fuselage showing ductwork.

It would appear that the P-43 system was sort of a trial run for the P-47. Turbo to the rear of the cockpit. Air intakes under the engine in the nose with the oval opening. Ducts and exhaust pipe running back and forth. Location of the intercooler is not positive but there are only a few possible locations based on air outlets. One is a slot at the very bottom of the cowl pretty much in line with the adjustable cooling flaps. Unlikely due to space constraints. The next outlet is a door/flap in the left wing root (don't know if there is one on the right to match.) in front of the landing gear. Seems small and may be possible location of the oil cooler outlet, P-47 oil cooler outlets were just slightly forward of this location. 3rd is a flap on the bottom of the aircraft behind the turbocharger. P-47 used lateral exits.

As to performance. Chart at WW II aircraft performance shows a top speed of about 290-293mph ? at sea level which is NOT 30mph faster than a F4F-3 more like 15mph and speed at 15,000ft for the YP-43 is 339mph. The YP-43 is flying with about 145 gallons of fuel and 250lbs of armament (two .50 cal guns go about 150lbs. .50 cal ammo is 30lbs per 100 rounds).
Now weight is not a big detriment to speed, it has a much greater impact on climb.
As to carrier use (not the P-43 as it stands) zero wind take-off for the P-43 at 6913lbs was 1070ft and landing speed was 93mph. Landing was using full flap.
The F4F-3 at 7432lbs (over weight fighter ) was 748ft and stalling speed without power at that weight was 78mph. With fuel burned off it was lower. Please take these figures into consideration when thinking about carrier fighters.
In order to be a carrier fighter the plane actually has to take-off and land from the majority of carriers in a particular navy. And some Navies had slow carriers with short decks.

 

[pinsog]

I've said it on this thread about 5 times, A P43 WILL NEVER BE A CARRIER FIGHTER, EVER EVER EVER EVER

Shortround, in thread 59 I said P43 is 20-25 mph faster than an F4F-3, not 30. BUT it is 30 mph fast up high, F4F-3 is 326 at 22,000. A P43 is 356 at 25,000. That is 30 mph 3,000 feet higher. At 22,000 feet the F4F-3 performance is already dropping and will only get worse. F4F is doing 312 at 14,200, P43 is doing 339 at 15,000, thats 27 mph difference.

P43 started out with 2 50's synchronized and 2 30's in the wings. It then replaced wing 30's with 2 wing 50's and then eventually moved all 4 50's to the wings.

They should have fixed/redisigned wing to accommodate normal fuel tanks instead of wet wings and deployed it to Pacific land basis instead of P40's and land based F4F's.

 

[Shortround6]

Sorry I wasn't clearer. Just using the P-43 as an example of why you can't take land plane X and hang a hook on it and presto-chango have a Carrier fighter.

I have my doubts about later P-43s being quite as fast as the YP-43 also.

I would also love to see a photo of a P-43 with wing guns only. Often reported in print but actual evidence seems a bit thin.

Using the P-43 as evidence that the turbo installation didn't have a fair amount of drag penalty doesn't hold up well due to the difference in wing size and wing characteristics. Not only did the F4F have a bigger wing but high lift wing sections are rarely low drag wing sections.
You need a closer airframe to make a comparison with.

 

[Elvis]

Something to remember with the P-43 and possibly the P-35....Those planes were not designed and built for carrier service,
To do that, the airframe and possibly the landing gear would have to be strengthened...then there's the marinization process, to help the thing survive at sea.
All of this adds weight and thus, degrades performance.
While on paper, the P-43 seems to outclass the F4F-3, you have to remember the Grumman was a flying tank because it was designed and built as a carrier airplane.
What you need to do is marinize the P-43 first, then compare subsequent performance numbers to whatever F4F you choose...I bet you'll find the performance numbers to be closer than what they are now.
As for the radial engines mentioned, again, we go back to weight.
All the twin row engines mentioned are around 1500 lbs., but most of the variations of the R-1820 are around 1000lbs.
...that's a 500 lb. difference and that can have a pretty fair effect on overall performance.
Yeah, the Wright engines were quite broad, but they were also lighter, yet were capable of similar power output.
This is probably what manufacturers noticed with that engine and why it was such a popular choice.


Elvis

 

[parsifal]

not necessarily the case that performance was downgraded by navalisation. sea hurricane had the same or better performance than new hurricane Is or IIs, and in some instances, published performance for the sea hurricane shows slightly better performance. Some opportunities were taken to improve aerodynamics and the like partly explains this

 

[Elvis]

Sea Hurricane also benefitted from a more powerful version of its engine and a different prop.
Could've been enough to bring things back to square, if you catch my drift. =)

 

[Shortround6]

As for the radial engines mentioned, again, we go back to weight.
All the twin row engines mentioned are around 1500 lbs., but most of the variations of the R-1820 are around 1000lbs.
...that's a 500 lb. difference and that can have a pretty fair effect on overall performance.
Yeah, the Wright engines were quite broad, but they were also lighter, yet were capable of similar power output.
This is probably what manufacturers noticed with that engine and why it was such a popular choice.

The R-1820 hadn't weighed 1000lbs since the "F" series of 1934/35. The "G" series (introduced in 1935/36) went about 1153-1210lbs with reduction gear and about 1105-1114lbs with direct drive. The "G-100" series went 1255-1290 introduced in 1937 and the "G-200" went 1290-1338lbs starting in 1939. Some of the early models stayed in production for certain applications after newer models came out so there was quite a bit of cross over.

The R-1535 went around 1100lbs and all production versions had a single speed supercharger. The R-1830 varied quite a bit, a few of the early ones were down around 1200-1300lbs (power was also around 900hp) but the majority of production engines, even before WW II were 1400lbs and up. P & W was working on two stage superchargers and didn't get around to fitting a 2 speed drive to the single stage until several years after Wright did. Perhaps another reason for some choices of engine?

 

[Shortround6]

Some land aircraft like the Hurricane and Spitfire had large wings to suit them to the small grass airfields, what with the fixed pitch props they needed all the help they could get for take-off. Low landing speeds also suited the Grass fields. This made transition to carrier decks easier. Planes with higher wing loadings and/or different airfoils may have had a much harder time.
Flight characteristics near stall also play a big part, a plane that maintains stability down to or just above stall is a big plus compared to one that starts to wander (yaw) or rock or porpoise as it approaches stall. Effectiveness of the controls at or near stall is also important. Some aircraft tended to loose control effectiveness at low speeds. Being unable or only slowly correct a mild swing/drift or wing drop could be fatal to a carrier plane while being within acceptable for a land plane.
Large control surfaces also mean more drag so the quest for 350mph carrier fighters on limited power has another complication.

 

[stona]

Flight characteristics near stall also play a big part, a plane that maintains stability down to or just above stall is a big plus compared to one that starts to wander (yaw) or rock or porpoise as it approaches stall.

The Spitfire/Seafire was a notorious 'floater'.
Something as simple as the instrumentation could have a serious effect too. The Spitfire ASI was designed so that close to landing/stall speeds the travel across the dial between 'safe landing' and 'inevitable crash' was somewhat smaller than the natural oscillation of the pointer. Landing on grass airfields, when the difference between the stall speed and landing speed was much larger this was not an issue. However, for deck landings, where the difference was very small indeed, much smaller than on US aircraft designed for carrier operations, it was very much an issue. It led to pilots adding a few knots 'for the wife and family', coming in a little fast and then floating over the arrestor wires and into the barrier(s) or slamming into the deck imparting forces at angles for which the Spitfire undercarriage and airframe was never designed. The consequences of either were often serious for the pilot and terminal for the aircraft.
Cheers
Steve

 

[Elvis]

The R-1820 hadn't weighed 1000lbs since the "F" series of 1934/35. The "G" series (introduced in 1935/36) went about 1153-1210lbs with reduction gear and about 1105-1114lbs with direct drive. The "G-100" series went 1255-1290 introduced in 1937 and the "G-200" went 1290-1338lbs starting in 1939. Some of the early models stayed in production for certain applications after newer models came out so there was quite a bit of cross over.

The R-1535 went around 1100lbs and all production versions had a single speed supercharger. The R-1830 varied quite a bit, a few of the early ones were down around 1200-1300lbs (power was also around 900hp) but the majority of production engines, even before WW II were 1400lbs and up. P & W was working on two stage superchargers and didn't get around to fitting a 2 speed drive to the single stage until several years after Wright did. Perhaps another reason for some choices of engine?

Oh probably, but you just backed up that part of my post. Thanks buddy! You're ok! =)

Elvis

 

[Elvis]

Some land aircraft like the Hurricane and Spitfire had large wings to suit them to the small grass airfields, what with the fixed pitch props they needed all the help they could get for take-off. Low landing speeds also suited the Grass fields. This made transition to carrier decks easier. Planes with higher wing loadings and/or different airfoils may have had a much harder time.
Flight characteristics near stall also play a big part, a plane that maintains stability down to or just above stall is a big plus compared to one that starts to wander (yaw) or rock or porpoise as it approaches stall. Effectiveness of the controls at or near stall is also important. Some aircraft tended to loose control effectiveness at low speeds. Being unable or only slowly correct a mild swing/drift or wing drop could be fatal to a carrier plane while being within acceptable for a land plane.
Large control surfaces also mean more drag so the quest for 350mph carrier fighters on limited power has another complication.

Likely why the reason for the huge wings on the F4U, as well...possibly that giant prop, too.


Elvis

 

[JAG88]

How do you guys think an ME109 would handle controlled crash landings on a carrier day after day?(Spitfire didn't like it)
How well would that tiny little fighter handle the weight gain of being navalized?

The wing was enlarged and the added weight wasnt that much (200Kg), and it got a more powerful engine (N). The landing gear was widened and strengthened as well.

It was not just the aircraft but the carriers and operating doctrine. It is no great trick to catapult small fighters into the air with drop tanks but range is not based on individual aircraft but the range of the group. First planes up have to orbit until the last planes are up. If the carrier only has two catapult s how long does it take to get the group in the air? The US planned on flying off, not catapult for a higher launch rate.
You are also back to operational radius depending on internal fuel for fighting, cruise home and a bigger reserve than land operations, you only have one landing "area" (task group) with a limited number of runways. You have to find it and then have enough fuel for ALL planes to land (including time out for several bad landings).
What is the range of the 109 with 10-15 minutes of combat and 30 minutes or more of reserves for finding the carrier and queuing up to land taken away from the internal fuel?

Ju 87s and 109s would use the catapults, the Fi 167s would not.

Each catapult could launch 1 aircraft per minute, that is a launch every 30s, so about 4 minutes for the biplanes and then 10 minutes to catapult the other aircraft. So, about twice as long as a IJN launch.

The Spitfire/Seafire was a notorious 'floater'.
Something as simple as the instrumentation could have a serious effect too. The Spitfire ASI was designed so that close to landing/stall speeds the travel across the dial between 'safe landing' and 'inevitable crash' was somewhat smaller than the natural oscillation of the pointer. Landing on grass airfields, when the difference between the stall speed and landing speed was much larger this was not an issue. However, for deck landings, where the difference was very small indeed, much smaller than on US aircraft designed for carrier operations, it was very much an issue. It led to pilots adding a few knots 'for the wife and family', coming in a little fast and then floating over the arrestor wires and into the barrier(s) or slamming into the deck imparting forces at angles for which the Spitfire undercarriage and airframe was never designed. The consequences of either were often serious for the pilot and terminal for the aircraft.
Cheers
Steve

One of the solutions the Germans implemented to make the 109T viable was to add spoilers to allow for a power on approach and prevent floating.

A LOT more work and development went into the 109T than into the improvised RN navalizations.

 

[stona]

A lot more work was required because a Bf 109 was even less suitable for carrier operations than a Spitfire.

It's why the 'T' was quite different from a standard 'Emil', the extra 1.18m on the wingspan being the most obvious of the 'improvements', whereas an early Seafire was not markedly different from a Spitfire.

At least the Bf 109 T would have had the benefit of a much longer deck for landing than those of British carriers, catapult launches and a surprisingly sophisticated arrestor system (by DEMAG), had the Graf Zeppelin ever become operational.

Cheers

Steve