>
> Hey Fred!
> Yeah, seems high to me as well, but I'm getting an
honest 172-175 mph
> GPS at 7500 ft with my 125 hp rated EA81
That's more reasonable within the math at that altitude,
Glenn. Dr. Sighard Hoerner is again motionless in his
grave! ;-)
> and I do not have the slick underbody fairings
> as on Alex's plane. When your'e trying to go fast,
> the aero mods can help more than more hp. Like
> this guy who went 214 mph on 65 hp!
>
> http://www.ar-5.com/sportav93.html
> The Arnold AR-5
A number of aerodynamic mods individually may have to add
up, before meaningful things start to happen. The main
thing Arnold arguably did was achieve laminar flow back to a
phenomenal 70% of chord, and claims to have proven so by the
usual methods. Hoerner, in the days before fiberglass, said
55% was pretty good construction methods. Also mimimal
cooling drag. He also had a really small prop with a really
big bite in pitch -- not a very practical airplane, but some
say a Cessna 150 ain't either!
Reg,
Fred F.
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