Topic: Large airplane engine

[gerhed]

Dual Allison V-12 s
Built by GM in 1943--they made 11 planes
Production cancelled in 1944.
Project cost $50 million

This engine at Glenn Curtis museum in Hammondsport, N.Y.
--would make cool coffee table with a little plexi !

[Damfino]

This engine at Glenn Curtis museum in Hammondsport, N.Y.
--would make cool coffee table with a little plexi !

I agree completely!
(Oh, and maybe a little reinforcement for the floor!)

[Don R]

They tried a lot of new ideas back then, the allison was a little under powered compared to the other engines of the day.

[hotpocket]

get that thing fired up and do an engine swap

[Bwatson]

make a cool coffee table if you had a very, very big living room.

[BeSeeingYou]

They tried a lot of new ideas back then, the allison was a little under powered compared to the other engines of the day.

I believe they had an ineffective supercharger making them perform poorly at high altitude.  Planes like the P-40 were powered by the Allison V-12 and were mainly regulated to the Pacific or Africa where most combat was at lower altitudes.  The Mustang was also originally powered by the Allison V-12 and it only became an effective fighter after being paired up with the British Merlin engine.

[demon78]

Was it normally aspirated?
Bill the demon.

[Frankencake]

I'll see your engine and raise you this:
http://en.wikipedia.org/wiki/File:Pratt_%26_Whitney_R-4360_Wasp_Major.jpg

[BeSeeingYou]

Was it normally aspirated?
Bill the demon.

No they had a single stage supercharger but like i said earlier it was not totally effective.  Later versions that powered the P-38 had a two stage supercharger and this was better but still suffered from some problems at higher altitude.  It was a robust engine that was much simpler to build and maintain than engines like the Merlin.

[mark]

I'll see your engine and raise you this:
http://en.wikipedia.org/wiki/File:Pratt_%26_Whitney_R-4360_Wasp_Major.jpg

This guy was stopped at the local store a while back. Darn engine is almost as big as the Jeep.

Forgot what he said it was off, other than being one of the last reciprocating-engine airliners.

[Frankencake]

They used them on the B-36.

I like the twin crankshaft design of the V12.  They must counter-rotate to spin a center shaft.

[Sam Green Racing]

This must be a first, Gerhed posting a picture without any weird music

Sam.

[dave500]

They used them on the B-36.

I like the twin crankshaft design of the V12.  They must counter-rotate to spin a center shaft.

if they turn a centre shaft they must turn in the same direction.,like an idler shaft.?all these aircraft engines are the pinnicle and the last of the era,even in todays modern cars and bikes its still the same old piston pump!only the ancillaries have changed.

[Frankencake]

They used them on the B-36.

I like the twin crankshaft design of the V12.  They must counter-rotate to spin a center shaft.

if they turn a centre shaft they must turn in the same direction.,like an idler shaft.?all these aircraft engines are the pinnicle and the last of the era,even in todays modern cars and bikes its still the same old piston pump!only the ancillaries have changed.

You caught me thinking backwards.  They DO NOT counter rotate.  Now how did they compensate for output differences in the two cranks?  I know that they were finely synchronized but there would inevitably be a difference between the two sides.  Hydraulic coupling like a torque converter? 

[demon78]

I dunno Srust I personally liked working on Merlins in fact it would be handy if some of the Merlins features were used on bikes.
Bill the demon.

[dave500]

They used them on the B-36.

I like the twin crankshaft design of the V12.  They must counter-rotate to spin a center shaft.

if they turn a centre shaft they must turn in the same direction.,like an idler shaft.?all these aircraft engines are the pinnicle and the last of the era,even in todays modern cars and bikes its still the same old piston pump!only the ancillaries have changed.

You caught me thinking backwards.  They DO NOT counter rotate.  Now how did they compensate for output differences in the two cranks?  I know that they were finely synchronized but there would inevitably be a difference between the two sides.  Hydraulic coupling like a torque converter? 

being geared linked ,the output differences would be like the differences between each cylinder of any multi cylinder engine,like two engines geared and timed together.

[dave500]

i saw an old short documentry years ago on ww2 aircraft engines made in the day and how they were built,then tested,then taken apart and inspected,then run again at half throttle for X amount then full throttle for a while,then taken apart,inspected,reassembled and run again,before being fitted to an aircraft,was this true of merlins?griffons?seems so much waste only to have it shot down or crash to build so much reliability into them.

[demon78]

I know I saw much the same thing on Orenda's ( powered Canadair F 86 Sabres, CF 100 Clunks and same for Arrow, Dave but this was before small computers were powerful enough to give useful projections and it was a way of figuring it out.
Bill the demon.

[gerhed]

My info says the "XP-75"--did have counter rotating propellors.

[BeSeeingYou]

I dunno Srust I personally liked working on Merlins in fact it would be handy if some of the Merlins features were used on bikes.
Bill the demon.

A beautiful engine no doubt but they had nearly twice the number of parts than the Allison from what I have read.  I remember reading about how poorly the Spitfires performed in the Pacific Theatre.  This was mainly due to the rougher conditions of jungle airstrips and the lack of sophisticated maintenance facilities that the Spitfire required.

[Don R]

I'll see your engine and raise you this:
http://en.wikipedia.org/wiki/File:Pratt_%26_Whitney_R-4360_Wasp_Major.jpg

My brother worked on those engines in the B50, it was a rebuilt B29  modified for more performance and reliability. There was also a tanker version. I saw a cut-away like that at a museum, twin turbos feeding a crank driven centrifugal supercharger!

[dave500]

I know I saw much the same thing on Orenda's ( powered Canadair F 86 Sabres, CF 100 Clunks and same for Arrow, Dave but this was before small computers were powerful enough to give useful projections and it was a way of figuring it out.
Bill the demon.

not just a prototype,every single engine was run then stripped and reassembled,i think ford also did this with 60s lincolns?

[gerhed]

This must be a first, Gerhed posting a picture without any weird music

Sam.

Sam,

I certainly don't want to disappoint my public.
Here's a recent sampling (short version)-click it!

http://i170.photobucket.com/albums/u251/gearheaded_photos/satbak2.swf

gerhed

[Sam Green Racing]

You're so kind. 

Sam.

[ZanVooden]

Here's a more modern use of the Allison engines... other than as a coffee table

http://lh3.ggpht.com/tractorpulling.sascha/RmLs8DJIUNI/AAAAAAAAuWs/GszyK2aaMio/s912/IMG_4242.JPG
 
not nearly as elegant as a fighter plane... I believe this one is in Germany, but the first one that came to my mind was a guy out of i believe Indiana. I remember helping out at the tractor pulls, using a buddies old Farmall M to pull some of these big monsters around the grounds to get them to the start line so they didn't have to burn more fuel than necessary. I remember a guy pulling in with this huge semi trailer and back out one tractor with duel allisons and second with triple allisons. Talk about an awesome sound..