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ACRO E-mail Archive Thread: [ACRO] AWAC aircraft

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ACRO E-mail Archive Thread: [ACRO] AWAC aircraft


Thread: [ACRO] AWAC aircraft

Message: [ACRO] AWAC aircraft

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From: ACCassidy at

Date: Sun, 28 Jan 2001 09:17:56 UTC


  Don et al,

The regulations state that excluded aircraft are "All designs of 260 hp or 
more unless approved by CIVA."

So for automatic eligibility you have to have installed LESS THAN 260hp. In 
other words 259hp is OK.

However, just looking at the plate on the side of a Lycoming doesn't tll you 
how much power the engine is putting out, because of the modifications that 
can lurk in and around it. The USA in particular has a flying culture that is 
beloved of squeezing more out of a certain number of cubic inches.

So if you were to turn at the AWAC up with an S-1-11B or an Edge540 or a 
Medidit 259, you had better bring with you a certificate from an independent, 
preferably government-owned, test laboratory, stating your engine has been 
very recently bench tested and found to produce only 259hp or less.

One of the problems with refining the AWAC regulations has always been the 
problem of policing any performance "formula" that might be agreed upon. 
Unmodified factory designs, like the Zlins, Yak 55s and so on are generally 
un-modified (outside USA) and come with a known factory performance level. 
But knowing what is in a home-built, what its true rate of roll and drag 
co-efficient are and so on is a great unknown.

One of the motivations behind the movement to remove the restrictions was 
because they would be so prohibitively expensive to regulate properly. But 
that proposal fell because some thought it would lead to aircraft and cost 
"inflation", because all the judges would for some reason mark Extra pilots 
higher than Pitts pilots.

You see how this can become a long story....

Alan Cassidy
IAC# 18506
Maidenhead, England


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