F4U F6F P-38 P-47 or P-51 Which plane was best by war's end

[The Jug Rules!]

Whoops! I cant see it...


Is it gone now?

 

[cheddar cheese]

Yeah it was a bit big, had to remove it. Possibilities of down-sizing it to a smaller size?

 

[The Jug Rules!]

I didn't look at it after I posted it...sorry!

 

[cheddar cheese]

Thats ok.

 

[Anonymous]

Well, in general I agree, all 3 were very good fighters.

As for the P-38 climb, the attached chart shows the P-38j at a takeoff weight of 16,415 lbs and a climb at 60" hg manifold pressure. My P-38 manual indicates that 65" manifold pressure was possible for the L model at 3000 rpm but it is not clear how long or under what conditions this could be used (it may not have been allowable for climb). It is clear from the nature of the graph that this is not a "normal" setting.

I've not seen a better climb rate for the P-38 listed in any reliable source. The only better climb rates I've seen are for the K model which of course was not produced.

=S=

Lunatic

 

[wmaxt]

Well, in general I agree, all 3 were very good fighters.

As for the P-38 climb, the attached chart shows the P-38j at a takeoff weight of 16,415 lbs and a climb at 60" hg manifold pressure. My P-38 manual indicates that 65" manifold pressure was possible for the L model at 3000 rpm but it is not clear how long or under what conditions this could be used (it may not have been allowable for climb). It is clear from the nature of the graph that this is not a "normal" setting.

I've not seen a better climb rate for the P-38 listed in any reliable source. The only better climb rates I've seen are for the K model which of course was not produced.

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Lunitic[\quote]

The limiting factor for high intake pressures in the P-38 was the charge cooling. Even in early models it was ok to use those settings for climb but once at altitude, inadequate cooling by the intercoolers in the rarified air would allow detonation and could not be used long.

C.C.Jordan in the p38 forum claims to have a AAF report of WEP climb at 4.91 to 20k and of course Planes and Pilots has the Lockheed graphs. The graph also shows a Clean Normal power 1,100hp at a little over 7min which dovetails nicely with the manuals 11min to 25,000ft climb with some external stores. I can understand your skepticism but normaly published specs are at 1,425hp and have to be taken with a grain of salt too.

I did not mean normal throttle setting but a Normal climb out. The flight manual settings are 3,000rpm and 54" Which is METO and at that weight it's carring some external stores too. The ferry climb conditions are lower.

wmaxt

 

[KraziKanuK]

 

[DAVIDICUS]

Nice chart RG_Lunatic.

I am surprised that the maximum speed data is so close between the P-51B and P-47D.

Sea Level
P-51B (359mph)
P-47D (354mph)

20,000ft.
P-51B (419mph)
P-47D (419mph)

Is that that data for the P-47D with the the paddle blade? The P-47D sure is a dog in a climb at critical altitude. (1,280 ft. min. @ 25,400 ft.)

And check out the take off distance! I recall reading the following joke known among P-47 pilots:

Q - How much runway does a P-47 need to take off?

A - All of it!

Why is the service ceiling so low? I thought the P-47 had a service ceiling of almost if not 42K?

 

[Anonymous]

Nice chart RG_Lunatic.

I am surprised that the maximum speed data is so close between the P-51B and P-47D.

Sea Level
P-51B (359mph)
P-47D (354mph)

20,000ft.
P-51B (419mph)
P-47D (419mph)

The P-47D was a fast plane. Also, note the figures for the P-51B are at MP not WEP (I'm not sure what WEP manifold pressure would be though - 70"?).

Is that that data for the P-47D with the the paddle blade? The P-47D sure is a dog in a climb at critical altitude. (1,280 ft. min. @ 25,400 ft.)

I don't believe the P-47 had a paddel prop or water injection. This chart is apparently from very early 1944 and the non-Vought data is older than the chart.

And check out the take off distance! I recall reading the following joke known among P-47 pilots:

Q - How much runway does a P-47 need to take off?

A - All of it!

Well, that is takeoff distance with full drop fuel and drop tanks. A fully loaded P-47 needed a lot of runway!

Why is the service ceiling so low? I thought the P-47 had a service ceiling of almost if not 42K?

US service ceilings were based upon a 500 fpm climb at MP (except where Normal Power is noted), where most other nations rated the service cieling based upon a 100 fpm climb at WEP. So it's totally apples and oranges. Most altitudes quoted on most sources use the 100 fpm rating so the cielings listed are much higher.

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Lunatic

 

[DAVIDICUS]

Thanks.

I'd sure love to get a hold of some data on the paddle prop P-47D. 8)

 

[Anonymous]

Thanks.

I'd sure love to get a hold of some data on the paddle prop P-47D. 8)

Unfortunately I don't think it is available. By the time the paddle props came onto the production line P-47's, the P-47D line was already terminal. Since no new P-47D orders were to be forthcomming, there was little need for such tests. The Paddle props and ADI were retrofitted to many P-47D's (including those with birdcage canopies) in the field. By that point, the testing was on the R-2800(C) powered models - namely the M and N.

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Lunatic

 

[DAVIDICUS]

I haven't seen any test data on the P-47N either for that matter. What was the climb rate and time to altitude numbers? Speed at altitude? etc.

Do you have anything on this? (Oh please, please, please ...)

 

[Anonymous]

I haven't seen any test data on the P-47N either for that matter. What was the climb rate and time to altitude numbers? Speed at altitude? etc.

Do you have anything on this? (Oh please, please, please ...)

Unfortunately no

There are some interesting documents on the P-47 at:

http://www.lanpartyworld.com/ww2/files/air-manuals/usaaf/

This includes some interesting doc's on the P-47 (and other planes) and the P-47N pilot handbook (which includes no climb/speed chart).

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Lunatic

 

[DAVIDICUS]

Yeah, I downloaded the pilot handbook hoping it would have some interesting performance figures.

It is an excellent site though with a wealth of information. Thanks for bringing that site to everyone's attention.

 

[Nonskimmer]

Yeah, some interesting stuff. Thanks RG.

 

[Anonymous]

I think RING'S PRO DOCS is the richest sight on the web for Primary Source Documents.

It is not easy to navigate all of it, as it is done by a variety of people in a variety of places, but it has some amazing documents.

Do yourselves a favor and download what you want as offline content (or however works for you). There is no telling when it might vanish. I've captured most of the aircraft material, but not much of the other material.

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Lunatic

 

[evangilder]

The P-47s had paddle blade props for most, if not all of the later models. Ask any former crew chief on a P-47 and they will tell you that the paddle blades were MUCH better than the Curtiss Electric "toothpick" blades. One of the guys at our museum said he was glad to see the Curtiss Electric Blades go. They often got runaways, or in some cases, the prop literally came apart while in flight!

Hard to really tell well from photos, but one is from the prototype, with the car-type door and the Curtiss Electric props. The other is the Hamilton Standard paddle blades. Like I said, the picture does not show it very well.

 

[Anonymous]

I've seen photos with thicker paddle blades than that:

My reading has indicated that the field unit upgrades to the Paddle props occured during the Spring and Summer of 1944, and became a production item on the P-47D-20-RE. Curtis also made paddle props for the P-47, and these were fitted to units produced at the Evansville plant.

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Lunatic

 

[evangilder]

That sounds about right. I just remember Joe saying the he "hated those damn toothpick props".

 

[The Jug Rules!]

The only information I got on the Jug after the Paddle blade prop was added was from The book that Robert Johson wrote. He said that he could stick with a Spitfire 9, and hang onto Me-109's and Fw-190's better than ever.