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Actually Red Admiral, Dan Whitney in his superb book Vee's for Victory is right and you are wrong. You are wrong in your interpretation of the Model Designations of U.S.A.F. Aircraft Engines table and wrong in discrediting a book you have obviously not ever even opened.
For example in the -45 row the Aircraft Engines table notes in the Description column that the -45 has an auxiliary second stage supercharger and in the Supch (Supercharger) column lists Geared, 9.5, 8.1:1, 6.85:1. Somehow you interpret that information to mean a single stage two speed supercharger.
Dan Whitney's Vees for Victory is incorrect in this regards. Theres a nice list published by Air Material Command which gives the model designations of USAF engines including details on usage, powers, displacement, supercharger details, prop details etc.
Single stage and two speed versions were; -45 -57 -93 -97
-101 -109 -111 -131
Under the protocols of the day all Army engines had odd dash numbers and all Navy engines had even numbers. The Navy used very few Allisons, mainly in airshipsAnother thing to note is that nearly all the models listed are odd numbered, virtually no even numbered models are listed.
I think you may find clockwise rotation engine is odd number and anticlockwise even numbered
That's a good thing, since the Allison was originally designed to power airships! =)Under the protocols of the day all Army engines had odd dash numbers and all Navy engines had even numbers. The Navy used very few Allisons, mainly in airships