P-40 with a Merlin ?

[awrabbit]

Hiya Folks.

I was watching the military channel last night and the show great planes was on they were talking about the P40 and said that the British only would order the plane if it had the merlin in it?

I didnt know this and it sparked my interest about how did it perform with the Merlin?
As it was way under powered with the allison. I always thought that with a more powerful engine it would be a pretty decent fighter.

Also in the show they said that the P-40's that the AVG received were built for the RAF but, I am pretty sure that these were equipped with the allison. I figured that some of you P-40 fans out there would have more info on this and could set the record straight.

What would be the performance differences with the  allison equipped P-40 and the merlin equipped P-40.
If the merlin was used on this plane did they use the 2 speed super charger ? which would make the plane of course have a better service ceiling and more speed. ( anyone have any data ?)

also they stated the the allison for the p-40 was not supercharged. did they ever use a super charger on this aircraft?  If so how did it perform ? how did the addition of the merlin change the over all balance of the air frame? I would have to think that the service ceiling would have increased by a ton  and it would of had a much inproved climb rate. It would be interesting to see the data.

I hate it when some of these programs that are supposed to be hilighting a particular air craft and they do not go into enough detail on the important aspects of what made it such a great plane. instead of giving us more information they leave us with more questions. but, still it is nice to see a program about any WWII aircraft.  it would be interesting to see more shows about all of the lend lease aircraft and how they were used and performed in the war. From what I understand the Russians loved the P-39's as well.


Regards

Rabbit

[awrabbit]

this is some of the info I came up with..... crap ! I hate when I post before i have had my first cup of coffee ! 

In 1941, P-40D Ser No 40-360 was fitted with a 1300 hp British-built Rolls-Royce Merlin 28 engine with a single-stage two-speed supercharger. It flew for the first time on June 30, 1941. This experimental P-40D could be distinguished from the stock P-40E by the absence of the top-mounted carburetor air scoop. The Merlin engine did much to overcome the limitations imposed by the Allison, and a total of 1311 examples powered by the American-made version of the Merlin that was built by the Packard Motor Car Company were ordered under the designation P-40F.

The P-40F and later versions were known by the name *Warhawk* in US service.

The first 699 planes of the P-40F series had no dash numbers, since the production block designation system was not yet in effect. The dash numbers were first used with the P-40F-5-CU model, which introduced a fuselage elongated from 31 feet 2 inches to 33 feet 4 inches in order to improve directional stability. This longer fuselage was retained in all later P-40 versions. The P-40F-10-CUs had manual instead of electrically-operated cowl flap controls. The P-40F-15-CUs had winterizing equipment, and the P-40F-20-CUs had a revised oxygen flow system for the pilot. A radio mast was fitted to late production P-40Fs.

The P-40F was powered by a Packard-built Merlin V-1650-1 twelve-cylinder Vee liquid-cooled engine rated at 1300 hp for takeoff and 1120 hp at 18,500 feet. Maximum speed was 320 mph at 5000 feet, 340 mph at 10,000 feet, 352 mph at 15,000 feet, and 364 mph at 20,000 feet. An altitude of 10,000 feet could be attained in 4.5 minutes, and an altitude of 20,000 feet could be reached in 11.6 minutes. Maximum range was 700 miles at 20,000 feet (clean), 875 miles (one 43 Imp gal drop tank), and 1500 miles (141.5 Imp gal drop tank). Service ceiling was 34,400 feet. Weights were 6590 pounds empty, 8500 pounds normal loaded, and 9350 pounds maximum. Dimensions were 37 feet 4 inches wingspan, 33 feet 4 inches length (P-40F-5-CU and later), 10 feet 7 inches high, 236 square feet wing area. Armament consisted of six 0.50-inch machine guns in the wings.

One hundred and fifty P-40Fs were supplied to the RAF under Lend-Lease. The RAF assigned them the name Kittyhawk II. The Kittyhawk IIs were offset from USAAF allocations 41-13697/14599. RAF serials were FL219/448. Unfortunately, P-40Ls were also mixed in with this lot with no mark distinctions, so it is impossible to tell which planes were Fs and which were Ls by merely looking at the RAF serial number. In the event, very few of these aircraft actually served with the RAF. FL273 and FL369-448 were returned to the USAAF for use in North Africa in 1942/43. FL230/232, 235, 236, 239/240 were lost at sea before reaching the RAF. FL263, 270, 276, 280, 383, 305, and 307 were handed over to the Free French, who operated them in North Africa. 100 were transferred to the USSR.

The designation YP-40F was unofficially assigned to P-40F Ser No 41-13602 used for experimental tests of the cooling system and the tail rudder. The coolant system was moved aft in several different configurations, including a mounting fitted inside a thickened wing-root section.

USAAF serials of the P-40F were as follows:


41-13600/13695       Curtiss P-40F Warhawk
41-13696       Curtiss P-40F Warhawk (order cancelled)
41-13697/14299       Curtiss P-40F Warhawk
41-14300/14422       Curtiss P-40F-5-CU Warhawk
41-14423/14599       Curtiss P-40F-10-CU Warhawk
41-19733/19932       Curtiss P-40F-15-CU Warhawk
41-19933/20044       Curtiss P-40F-20-CU Warhawk

A number of P-40Fs were selected at random, withdrawn from operational service, and fitted with Allison V-1610-81 in place of their original Merlins. These planes were intended for training duties. These were redesignated P-40R-1. Similar conversions from the P-40L were designated P-40R-2. Army records report that over 600 such conversions were made, but only 70 such conversions can be confirmed by serial number


Here is the link for all of the information:  http://home.att.net/~jbaugher1/p40.html

[B4Buster]

I really don't know a whole lot about P-40s equipped with Merlins but from what i'm told it didn't make a huge difference

[Captain Virgil Hilts]

The Allison V-1710 was equipped with a two stage single speed crankshaft driven centrifugal supercharger. As such, it could only be tuned for peak power for one narrow altitude range. The gearbox that drives the supercharger would have a gear ratio selected to produce the correct boost for a given altitude. There were proposals to equip the V-1710 with a two speed two stage supercharger, but it was never done. The P-38 solved the problem with a turbocharger. It complimented  the supercharger by adding the boost necessary to maintain sea level performance to a very high altitude, and a waste gate prevented the turbocharger from over boosting the engine.

Aircraft engines of the day, especially inline Vee types, were very low compression, usually in the 5.5:1 zone. Without supercharging they'd have never been able to produce even a 1/2 HP per cubic inch. So without a supercharger, a 1650 Merlin would make 825HP or less, and a 1710 Allison would make 855HP or less. There'd have been no need for high octane fuel either, as a 5.5:1 compression ratio, unsupercharged, would run on 80 octane or less.

[Treize69]

Don't listen to what that crap show says anyway, I dunno who writes and edits it, but they're idiots. Just in the P-40 show, for example- they were talking about the development of the P-40 from the P-36... while showing pictures of the North American P-51 protoype, claimed that the P-39s nose armament was one 37mm cannon (which it was) and four .30 MGs (which were in the wings, the nose was 2 .50s), and talked about the Brits "only" accepting P-40s if they had a Merlin, when they had large numbers of Allison-engined P-40Bs and Es (which they called the "Tomahawk" and "Kittyhawk") long before the Merlin-engined F was a gleam in Curtis' eye.

Between the horrible research and the insanely boring host who obviously has to attempt to memorize and practice all the inane and pointless questions he asks, I have no idea how that show ever got picked up. In fact, as bad as "Showdown" was, I can't figure out how they gave that guy another show to host. Is he related to the programming director or something?

[Guppy35]

There were a couple of P40 variants with single stage Merlins.  Ironically they were flown by USAAF units in North Africa while the RAF squadrons flew Allison versions.

There were some Merlin P40s used in the PTO as well on the Canal and elsewhere.  You can spot a Merlin P40 by the lack of air intake on top of the nose.

It was not a British specific order by any means as I don't believe they got many.  I think I've seen one photo of an RAAF operated Merlin P40.

THe Merlins were being built under license in the US

[1pLUs44]

Don't listen to what that crap show says anyway, I dunno who writes and edits it, but they're idiots. Just in the P-40 show, for example- they were talking about the development of the P-40 from the P-36... while showing pictures of the North American P-51 protoype, claimed that the P-39s nose armament was one 37mm cannon (which it was) and four .30 MGs (which were in the wings, the nose was 2 .50s), and talked about the Brits "only" accepting P-40s if they had a Merlin, when they had large numbers of Allison-engined P-40Bs and Es (which they called the "Tomahawk" and "Kittyhawk") long before the Merlin-engined F was a gleam in Curtis' eye.

Between the horrible research and the insanely boring host who obviously has to attempt to memorize and practice all the inane and pointless questions he asks, I have no idea how that show ever got picked up. In fact, as bad as "Showdown" was, I can't figure out how they gave that guy another show to host. Is he related to the programming director or something?

I relatively enjoyed Showdown Aircombat. They just made the graphics cheesy. I watched a lot of the P-40 show, and I liked it.

[Widewing]

Both the P-40F and P-40L were powered by the Packard built V-1650-1 Merlin.

P-40F: 1,311 delivered
P-40L: 1,300 delivered

Except for the first P-40F-1-CUs delivered, all Merlin powered P-40s were "long tail" types (extended tail).

Note that the Merlin offered slightly better mid altitude performance, making best speed about 5k higher than the P-40E. Max speed and climb rate differed little, if at all.

In the desert of North Africa, the Merlin powered P-40s required more maintenance than the Allison models. Largely due to the Merlin's bottom breathing carburetor sucking in far more dust and sand (F and L models don't have the carburetor intake above the engine as does the Allison P-40s). Pilots stated that the Merlins were more difficult to manage than the Allison as they required more attention relative to cylinder head and coolant temperatures. Merlins had a greater tendency to overheat, especially while running on the ground.


My regards,

Widewing

[B4Buster]

Yup, I watched those "Greatest Ever: Planes" show last night. chuckled when they used the same plane as the so called "P-40 prototype, and the P-51 prototype"

I also thought Showdown was a bust.

[Krusty]

I stumbled across a website either on the USAF or a museum webpage network, and folks could leave comments on the sub-pages. On the P-40 page there was very little info, but somebody asked if there was much difference between the versions. Somebody replied saying they had flown them in the PTO and there wasn't any noticable difference between the Merlin/Allison versions. Said there wasn't any noticable difference until the N model.

Anecdotal, but from somebody that claimed to fly 'em in WW2.

[Guppy35]

Both the P-40F and P-40L were powered by the Packard built V-1650-1 Merlin.

P-40F: 1,311 delivered
P-40L: 1,300 delivered

Except for the first P-40F-1-CUs delivered, all Merlin powered P-40s were "long tail" types (extended tail).

Note that the Merlin offered slightly better mid altitude performance, making best speed about 5k higher than the P-40E. Max speed and climb rate differed little, if at all.

In the desert of North Africa, the Merlin powered P-40s required more maintenance than the Allison models. Largely due to the Merlin's bottom breathing carburetor sucking in far more dust and sand (F and L models don't have the carburetor intake above the engine as does the Allison P-40s). Pilots stated that the Merlins were more difficult to manage than the Allison as they required more attention relative to cylinder head and coolant temperatures. Merlins had a greater tendency to overheat, especially while running on the ground.


My regards,

Widewing

The USAAF carrier launched P40s during Operation Torch were all Merlin birds with the 33rd, 57th and 79th FGs that flew them until they transitioned to Jugs.  The 325th also had Merlin P40s if memory serves.

[beau32]

Here is a topic on another forum im on dealing with the powerplant of the P-40.


http://www.ww2aircraft.net/forum/aviation/fun-wwii-what-if-16105.html

[Guppy35]

Allison engined P-40 with the intake on top


Merlin engined P40 without the intake on top.

[MiloMorai]

The Allison used a down draught carb while the Merlin used an up draught carb. Therefore, the intakes had to be positioned like they are.

[Angus]

Wonder how the performance compares. Anyone?