Pratt & Whitney 28 cylinder Radial Engine

[stevemon]

Pratt & Whitney 4360 Wasp engine introduced in 1944. Basically, the engine was 28- cylinder four-row air cooled radial engine. Each row of pistons was slightly offset from the previous, forming a semi-helical arrangement to facilitate efficient airflow cooling of the successive rows of cylinders, with the spiraled cylinder setup inspiring the engine's "corncob" nickname. A mechanical supercharger geared at 6.374:1 ratio to engine speed provided forced induction, while the propeller was geared at 0.375:1 so that the tips did not reach inefficient supersonic speeds. Initially, it developed 3,000 horsepower, later models gave 3,500 horsepower.
            The 4360 powered the B-50,  successor to the B-29 and later the B-36, to name a few. And although reliable in flight, the Wasp Major was maintenance-intensive. Improper starting technique could foul all 56 spark plugs, which would require hours to clean or replace. As with most piston aircraft engines of the era, the time between overhauls of the Wasp Major was about 600 hours when used in commercial service.

http://www.vimeo.com/16117810

(Go to the link below the picture)

[Top Speed]

Very cool video!  Thanks!

[Steve Wood]

Those radials were truly works of art....Motormi nd Mike will be trying to put one in his buick pretty soon

[tb3]

super charged and turbocharged!
 
One of my professors was a flight engineer on the b36. (his flight jacket is on display underneath the b36 at wright patterson af museum.
He had several great stories.
the b36 had 6 of those engines. (plus a pair of jet engines on each wing tip)
I remember him talking about the first time he taxi'd in that thing.  he looked out one of the windows and he swore he could see the concrete under those monster props shaking like it was gonna bust

[tb3]

or wait, 
was it only supercharged?
maybe I'm thinking of the r985 radial.  some of those where turbo and supercharged.
 
to late to think, lol!  I'll remember later

[tb3]

dang it stevemon!!!
your gonna make me read the article, aren't you?!!!
 
 
 
 
 
 
 
 
too late!
it was gonna bother me.
 
 
 
 hence the model designation. Initial models developed 3,000 hp (2,240 kW), and later models 3,500 hp, but one model delivered 4,300 hp (3200 kW) using two large turbochargers in addition to the supercharger. Engines weighed 3,482 to 3,870 lb (1,579 to 1,755 kg), giving a power-to-weight ratio of 1.11 hp/lb (1.83 kW/kg), which was matched or exceeded by very few contemporary engines.
Wasp Majors were produced between 1944 and 1955; 18,697 were built.
 

[stevemon]

My work is through here. 

[Steve Wood]

I still remember the image of a B36 that I saw fly over my house when I was about 7.

It has not been that long since some "modern" crop dusters were still using old R1340 engines.   The ground did shake when they flew over while spraying.

[tb3]

I would love to have witnessed a fly over of one of those behemuths.
 
theres a story about a group of volunteers that had one pretty close to being restored to airworthyness condition, but the us govt shut them down.  they where concerned it could get into the hands of a third world country 

[Steve Wood]

you could put most third world countries inside of one

[SuperSix]

you could put most third world countries inside of one

Well, the Earth is the 3rd planet from the sun doesn't that make all countries third world?

[Steve Wood]

If you still use base10