From: Iskandar Taib <ntaib@silver.ucs.indiana.edu>
Subject: Re: Napier Sabre engines (fwd)
Organization: Indiana University
Date: Wed, 14 Oct 1992 15:36:11 GMT


From Iskandar Taib <ntaib@silver.ucs.indiana.edu>


From Iskandar Taib <ntaib@silver.ucs.indiana.edu>

Jim Davies and I have been exchanging some very interesting letters
about engine development. He seems to be a veritable encyclopedia of
aviation engineering lore. I suggested that he post this information 
so he's given me permission to edit and post some of these letters. 
I will leave as much of the text in as I can since it will detract 
from the coherence of the exchange if I remove too much:

jimd@sfu.ca writes:
|ntaib@silver.ucs.indiana writes:
||jimd@sfu.ca writes:


|||All WW2 A/C engines were 4 stroke typees and supercharged. Only the RR
|||Crecy was a two stroke. While it was fully developed, it was a victim
|||of Turbojet development, like the V-2220 and the C-W R-2160 (corncob)
|||a 42 cyl. 6-row, water cooled radial. I believe a lot of WW2 R&D that
|||went into these engines was later used in automotive engines. For
|||instance, all the engineering features introduced in the last 15 years
|||were common in WW2 A/C engines, and were first mass produced in the
|||war years. Alas, try finding any information! The search is
|||entertaining, however.
||
||Hmmm.. I'll have to look. We don't have much of an engineering school 
||here but there just may be books on the subject. 
||
|Please do! Some books I would like to find include:
|the following volumes of:United States Army in WW2; compiled by The
|Center of Military History US Army, in the Technical SServicesseries
| 1 the Ordnance Dept: Planning Munitions for War
| 2 the Ordnance Dept: Procurement and Supply
| 3 the Ordnance Dept: On Beachhead and Battlefront
|These were originally published in the earl 50's. I have some extracts
|from these books, courtesy oy US Army, and they are VERY interesting.
|Also any of the many Glenn D Angle books will be found to be
|interesting.  ing.   ssevices
|
||What was the RR Crecy? 
|In my first note to you was a very short bit about this engine. Let mr
|know if you didnt get it! Ive got a fair bit of info on this engine.
|One of the advantages of a 2-stroke is the higher volume of exhaust
|gases. At high altitude and speeds, the exhaust gas of this engine
|contributed a significant amount of total thrust, in fact the exhaust
|was ducted out the rear in a tube identical in shape to turbojet exhaust.
|Was it ever used in anything? Sounds like a 
||deviation from the usual naming of their engines after birds of prey, 
||which apparently continues to the present day jet engines. Unless a 
||"crecy" is a bird of prey, of course..I always thought it was a town 
||in France.
||
|Yes, and a battle site also, I think. As a drop-in replacement for the
|merlin, I shudder to think of the racket 4000 of these ((1000
|lancastersX4 engines) would have made over germany in their nightly
|forays! talk about pschy. war.
||
|One of the things that intrigues me about these engines (WW2 aircraft
|engines) is that many of their features are becoming standard in cars,
|now that US govt regs (CAFE and Emmissions) are forcing an increase in
|engine efficiency. Several car companies, for instance, are developing
|2-stroke engines, and of course, turbocharging, supercharging,
|aftercooling etc. etc. were first either developed or volume produced
|for WW2. Nitrous Oxide injection, currently the darling of the
|performance crowd was developed by both germans and brits, primarily
|for the photo recon wars. In fact, nitrous was obsolete by '44. The
|germans going to pure oxygen injection, and the brits to 150 octane
|gas, not to be confused with 115/145. Of course, octane
|enhancement/detonation suppression is the gate through which power
|development must be forced. We won that race, and the germans lost it,
|sometimes by only 7 m.p.h. (87 vs 100 octane avgas) as in the Battle
|of Britain. we can thank Standard Oil (and the US Army) for that
|little trick. They supplied all the fuel for both sides. 
||Thanks!
||
||Iskandar

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Iskandar Taib                          | The only thing worse than Peach ala
Internet: NTAIB@SILVER.UCS.INDIANA.EDU |    Frog is Frog ala Peach
Bitnet:   NTAIB@IUBACS                 !
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