Warbird Information Exchange

On the Allison V-1710, engine rotation is determined during build up. The major difference is the way the crankshaft is installed. The same crank is used for both rotation directions, but it is swapped end for end when it's installed in the lower crank case. An idler gear in the accessory drive is repositioned for L/H rotating engines so that all the accessories and the cams still rotate as if they were in a R/H rotation engine.
The only components that rotate "backwards" in a L/H engine are the crankshaft, the reduction gears in the nose case, and the oil scavenge pump gears in the nose case. Everything else stays the same as a R/H rotation engine.

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Rod Schneider
Ball Ground, Ga

Thanks. Very interesting.

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Well if I can't rollerskate around my playpen while smoking and drinking a beer, I'm staying home..

Thanks for the correction/clarification Rod.

Somebody was pretty clever to design that! I love stuff that is ingenious, simple and clever all at the same time.

Andy Scott

It's really something when you think about it, they were very advanced in their design. Overhead cam, roller rockers, 4 valves per cylinder, and single point fuel injection into the face of the supercharger. Not bad specs for a "modern" engine today!

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Rod Schneider
Ball Ground, Ga

WW1 engines were pretty amazing too, overhead cam on some in those days and the way they worked out rotary engines such as the Gnome monosaupape. Those guy were way ahead of their time when you compare their stuff to car engines of the time and for years after which were mainly sidevalve except for the very expensive specialist cars.Sorry it's off thread a bit.

Anyone have an email address for Mr. Kirchner? I'd like to contact him and offer him the services of my machine shop and aluminum foundry.

Thanks,
Barry
http://www.blackcrossaviation.com

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It was a good idea, it just didn't work.

Fantastic!! Any New Pic.s ? Updates?

Nice to see another Hawk nearing its first flight... thanks for sharing the photos.


Fade to Black...

What I understand about long nose or short nose Allison V-12’s is that the long gear cases used epicyclic reduction gearing because it allowed better streamlining, and the short cases used spur gears for strength. The epicyclic gearing was limited to about 1000 HP, so the switch was made to spur gears to stand up to higher HP engines.

Hi,

I don't suppose there's any photos of the inside of the main junction box in the fuselage?


Bigslim