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

stona said:

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.

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How so? The 109 was very docile in the approach to landing, very stable, and the slats allowed you to ride the stall with confidence, something that a Spit pilot would not do if he wanted to live, hence the extra speed and consequent floating.

Best

wuzak said:

Thanks Tomo.

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

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The intercoolers were located about two feet in front of the turbo. Air was supplied from the two inboard intakes under the engine. It looks like they discharged into the fuselage just like the B-17 did with it's wing mounted units.

P-66 was close. Maybe with the F4F engine it could reach 350 at a higher altitude. It did need some attention for some fixes and added weight of strengthening the structure and landing gear would have affected climb but not so much top speed. Wing area was a bit small at 197 sqft., but it was only 12 sqft less than the carrier qualified F2A. Weight was a bit heavier, though. Still the wing loading of the P-66 at gross was 36 lb/sqft was less than the F4U-1 at 38 lb/sqft. So some weight leeway was available.

JAG88 said:

How so? The 109 was very docile in the approach to landing, very stable, and the slats allowed you to ride the stall with confidence, something that a Spit pilot would not do if he wanted to live, hence the extra speed and consequent floating.

Best

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The Me 109T lead to the Me 109G based Me 155 also with extended wings, I think they were laminar flow profile like the Me 309 so it would have been quite fast despite the enlarged wing.. When the carrier program was cancelled the Me 155 was retargeted as a high speed bomber and high altitude aircraft. Due to engineering capacity shortages at Messerschmitt it was transferred to Blohm and Voss and became the BV155. Here it was heavily re-engineered thereby making manufacture impossible. The BV155 definetly had laminar Profile wings. This was in part driven by changing over from DB605 and then the high altitude DB628 (essentially a DB605 with a variable pitch 2 stage supercharger) and then the DB603 with a turbo charger. It did fly, service ceiling about 56,500ft.

The original Me 155 carrier version was expected to have a speed of 402 mph with the DB605A. This is about the same as the Me 109G1 at 1.3ATA or the Me109G6 at 1.42ATA.

It's curious to think of the "T" carrier version of the Me 109 to have continued. A Me 109F or Me 109G with the extended wings.

The extended wings would have provided for high altitude flight, better turn radius, STOL, a place to store fuel and a place to locate extra guns without resorting to the high drag Bulges of the Me 109G6 gun covers.

JAG88 said:

How so? The 109 was very docile in the approach to landing, very stable, and the slats allowed you to ride the stall with confidence, something that a Spit pilot would not do if he wanted to live, hence the extra speed and consequent floating.

Best

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The Seafire had to fly very close to the stall to make a carrier landing, three knots above the engine on stall speed or just 1.05 Vse. For comparison, US Carrier aircraft were designed to land at 1.2Vse, a relatively large margin.
The extra few knots ('for the wife and kids') were usually added because the air speed indicator had such a coarse scale, incapable of reading that accurately,the needle vibrating over an eighth of an inch representing about 10 knots, at least according to Seafire pilots who were there and survived.
Experienced pilots ignored it and flew by the seat of their pants, trusting the trusting the tail buffet stall warning to tell them they were about to fall out of the sky.
The 'float' was actually caused not by excessive speed but by the inescapable consequences of the V squared law. When a pilot cut the power to land and the slipstream speed reduced, the extra lift given by the positive angle on the elevator also reduced. The tail then lost a good deal of its lift and inevitably fell. The consequence of this was an increase in mainplane incidence (as if the pilot had pulled back on the stick) and corresponding increase in mainplane lift leading inevitably to the 'float'. This was a function of the Seafire and all but the Mk I Spitfire's aerodynamics. Most aircraft, including the Bf 109, have 'negative lift' on the stable tail surfaces, particularly in a landing configuration, meaning that the cutting of the power produces, at worst, a nose down pitch. This was quite pronounced on the Bf 109 T and considered, if not a problem, then something that pilots would need to be aware of.

The Bf 109 could land with a larger margin over the stall (about 7 knots) thanks to the very good arrester system, but this was not a function of any quality of the aircraft. Landing at 128 kph an arrested landing run of just 26m with a deceleration force of 2.8g was attained in tests.
The longer wing and the 'auftriebzerstorer' made it safer to land. Such modifications were never considered necessary on the Seafire, even later versions, but then the Spitfire had a much more sophisticated wing design, not requiring slats or other 'high lift' devices to increase lift at the lower end of its speed range.

Then we come to the undercarriage! Both aircraft were designed with narrow track undercarriages (remarkably similar track in fact) and for operation of grass fields. Neither was ideal for carrier operations, but the modified struts used on the Bf 109 T did nothing to improve the horrible geometry of the Messerschmitt system. It is true that more than 500 test landings were made without a serious accident at Travemunde, but that is not representative of service pilots landing the aircraft on a carrier deck at sea. It did have some serious accidents in development, very nearly killing none other than Fritz Wendel in April 1941. Whether the Messerschmitt would have been any safer or more successful than the Seafire in real world operations we'll never know. I'd be amazed if it was any better.

Both were aircraft designed with no consideration of carrier operations. Nothing about them was really conducive to making a successful carrier aircraft. The extensive modifications to the 'Emil' may have made it capable of carrier operations, just as adding a hook and making a few minor modifications did the same for the Spitfire, but neither would ever compare to aircraft specifically designed for such a role.

Cheers

Steve

Thx for the detailed response.

I would argue that the spoiler would have certainly helped with the floating and solved one of the main issues of the Seafire and that the stall behaviour in landing configuration of the 109 was better than the Spitfire's giving ample warning and chance to recover making it safer to land, as far as that aspect is concerned. The arrestor system made a faster landing posible, but if desired a 109 pilot could approach its stall speed with a confidence that no Spit pilot would, thst was a natural advantage of the 109 and an important one for a carrier aircraft.

Would the 109 have suffered as much as the Seafire did at Salerno?

The longer wing was a mere extension of the original one IIRC, not much of a modification.

I agree that strengthened or not the landing gear would have been its main issue.

I see the fact that the improvised Seafire was made to work more as a matter of need rather than suitability per se, the RN would have benefitted from some development work on the spit as the KM requested on the 109 IMHO.

The Spitfire gave ample warning of the stall, it's how experienced pilots landed it so very close to the power on stall speed, just three knots above Vse.
The tail buffet stall warning was often premature in service aircraft, anything that interfered with the airflow over the wing root could cause an early stall warning and many service aircraft had things that could cause this. The two principle culprits were badly fitting engine cowlings and gun camera hatches. This was a critical area of the wing and anything disrupting the airflow here, at low speeds, could cause the whole wing to stall. It's not therefore surprising that many pilots would ad a few knots 'for the wife and kids'.
Cheers
Steve

stona said:

The Spitfire gave ample warning of the stall, it's how experienced pilots landed it so very close to the power on stall speed, just three knots above Vse.
The tail buffet stall warning was often premature in service aircraft, anything that interfered with the airflow over the wing root could cause an early stall warning and many service aircraft had things that could cause this. The two principle culprits were badly fitting engine cowlings and gun camera hatches. This was a critical area of the wing and anything disrupting the airflow here, at low speeds, could cause the whole wing to stall. It's not therefore surprising that many pilots would ad a few knots 'for the wife and kids'.
Cheers
Steve

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I apologize, I was thinking of the Sea Hurricane and its wing drop, dont you just love aging?

JAG88 said:

dont you just love aging?

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Oh yes, I know the feeling well
Cheers
Steve

tomo pauk in thread #60 mentioned a turbo F4F. I had thought about it before but until I finally ran some numbers I didn't realize how big a difference it would actually make.

Original 2 speed 2 stage P&W R-1830-76:
1200 hp for takeoff
1100 hp from SL-2500 feet
1050 hp from 4800-11000 feet
1000 hp from 12200-19000 feet

with a P&W R-1830-47 with a turbocharger (same engine as the P43 Lancer)
1200 hp from SL-25000 feet

SL speed increases from 278 to 286
Speed at 5500 goes from 295 to 308
Speed at 13000 goes from 313 to 332
Speed at 19000 goes from 330 to 350
Speed at 22000 goes from 326 to 351

The F4F-3 speed numbers above included 150 pounds of armor and a self sealing fuel tank.

Drag should be identical, F4F-3 already has an intercooler so just plumb turbo into existing intercooler. I believe the weight would remain nearly the same as the weight of the turbo, 135 pounds, would be offset by the lighter single speed single stage engine that goes with it. I believe the best place for the turbo would likely be where it was on the P43 Lancer, but the pipe/plumbing would probably needed to have been done in the original prototype, not sure if there was room for the exhaust pipe and return pipe to be retrofitted later.
I also believe climb would be substantially improved as well as you would gain 100 hp down low, 200 hp from 12200-19000.

At 25000 feet HP jumps from 860 to 1200.

Performance virtually equal with the Spitfire mkII at 5000 feet and surpasses it above 20,000 and should continue to increase with altitude. (I can't find any speed data on the F4F-3 above 22000 feet)

pinsog said:

the pipe/plumbing would probably needed to have been done in the original prototype, not sure if there was room for the exhaust pipe and return pipe to be retrofitted later.

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I've actually seen (and sat in) a spacious, luxuriously appointed passenger compartment below and behind the cockpit of an FM2. Now I know an FM2 isn't an F4F-3, but they can't be all that different. I was impressed with the spaciousness inside that barrel fuselage. Even the "busy" area around the landing gear actuators didn't have the crammed in look I was used to seeing in more modern aircraft. And remember, the -3 had a hand crank manual retraction system, so even less machinery down there.
Cheers,
Wes

Do you know what diameter the exhaust pipe from the engine to the turbo would have to be? Pipe from the turbo back to the engine?

I'm not sure about diameter of the piping, however, there was the XF4F-5, with R-1820 + turbo. Seems like the B-17Bs were delivered with similar powerplant from second half of 1939 on - 1200 HP up to 25000 ft. No problems encountered when flying to Brazil and back (in several 'hops', of course).
Might be an interesting read: link

tomo pauk said:

the B-17Bs were delivered with similar powerplant from second half of 1939 on - 1200 HP up to 25000 ft.

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That's not actually what your Joe Baugher page says. It describes a (no mention of a turbocarger) -51 engine in the B17B that can only manage 900 hp at 25,000, which is 400 ft ABOVE its service ceiling.
Cheers,
Wes

An F4F-3 will climb to 10000 feet in 3.5 minutes on 1050 hp and 20000 feet in 7.6 minutes at 1050 hp up to 12000 feet and then 1000 hp from 12000-20000 feet.....(light on fuel)
Is there a way to calculate the climb to 10000 or 20000 feet if you have a turbocharged engine with 1200 hp available from sea level up to 25000 ft?

XBe02Drvr said:

That's not actually what your Joe Baugher page says. It describes a (no mention of a turbocarger) -51 engine in the B17B that can only manage 900 hp at 25,000, which is 400 ft ABOVE its service ceiling.
Cheers,
Wes

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Indeed, no turbo is mentioned.
The speed-at-altitude and ceiling figures are in major mismatch at J.B's page, though.

pinsog said:

...
Is there a way to calculate the climb to 10000 or 20000 feet if you have a turbocharged engine with 1200 hp available from sea level up to 25000 ft?

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Maybe this might be of use: link

I have been using that link tomo pauk. In fact, it is one reason I finally did the caculations to see what a turbocharged F4F-3 would do. It appears to me that the smaller wing of the P43 gives it a higher top speed down low, while the larger wing of the Wildcat gives it a better climb until the power of the P43 overcomes the higher lift of the F4F-3. Also, apparently, top speed above 20000 feet appears to be about the same (if they were both turbocharged) making me think that the thinner air at altitude makes less difference to the slightly draggier F4F-3.

Looks to me like a turbocharged F4F-3 was a missed opportunity from 1940-mid 1943

GrauGeist said:

There was a P-51 (P-51-NA), s/n 41-37426 (BuNo. A57897) that was evaluated by the USN long before they considered the P-51D.

View attachment 365171

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Dave - doable but while production of the NA-73 began in spring 41, modifying the Mustang for just carrier landing qual - much less hosting a nasty inline/glycol cooled engine was Never going to be bought by USN. The earliest possible date for Carrier qual 'qualified' acceptance would have been perhaps mid 1942 for the NA-73. The NA-91 shown above first flew in May, 1942 and was acquired from Brit order.At that time the F4U had much more upside. Further, adding wing racks/plumbing was NA-97 (A-36) first flying in Fall 1942. Earliest delivery to squadron level would have been mid 1943 if USN committed in April 1942.

Tomo Pauk,

Could you please explain "Calibrated Climbing Speed" to me?
I'm having a little trouble understanding the figures they show in that link you posted.

Elvis said:

Tomo Pauk,

Could you please explain "Calibrated Climbing Speed" to me?
I'm having a little trouble understanding the figures they show in that link you posted.

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Are you referring to post #95? I meant to show the F4F-3 climb times to 10000 feet and 20000 feet while also including the hp of the engine at certain heights. 1100 hp from SL-3500 feet, 1050 from 4800-11000 feet, 1000 hp from 12,200-19000 feet.

My question is, if an F4F-3 was turbocharged with 1200 hp from SL-25000 feet, weight and drag unchanged, what would the time to climb be up to 10000 and 20000 feet? Is there a way to calculate the increased climb rate?