Hi Kostas,
Several questions:
1. What is your static rpm at full power?
2. What is your Indicated Airspeed at 2400 rpm?
3. Is your engine still the original 75 hp?
4. Do you have the original wood Sensenich prop or a Metal McCauley?
5. What is the pitch and diameter of your prop?
The reason I ask is that your performance appears low.
According to Ercoupe Service Memorandum No. 37, Appendix "A", a 415-C
at 1260 lb. gross., 75 hp fitted with a McCauley 1A-90 73-51 prop and
"air conditions...very close to standard for all of of the tests"
achieved 109 mph at 2275 rpm. With that prop at 1260 gross wt. they
were able to take off in 520' observed 710 fpm climb.
The preceding is better performance than most get with the 85 hp
"upgrade" with 71 " diameter props. I believe that is because of two
things. The earlier "steel" main landing gear had less drag than the
later aluminum main landing gear, and the larger diameter prop was more
efficient (so long as the engine could spin it up to a maximum rpm in
flight of 2500 rpm).
Regards,
William R. Bayne
.____|-(o)-|____.
(Copyright 2010)
--
On Jun 13, 2010, at 05:24, kostas vegas wrote:
Hartmut
I'm quite happy now with the power produced by the engine.
I can see up to 2400 rpm straight & level and usually I'm cruising
with 2100 but the airplane seams is hold by drag.
With a new ASI and GPS I never see more than 90mph cruising.
Let's hope as you say that this is the last trouble.
I'll keep you posted.
Kostas
--- Στις Κυρ., 13/06/10, ο/η Hartmut Beil <[email protected]> έγραψε:
Από: Hartmut Beil <[email protected]>
Θέμα: Re: [ercoupe-tech] Aileron hinge placement
Προς: [email protected]
Ημερομηνία: Κυριακή, 13 Ιούνιος 2010, 11:06
Kostas.
Let's hope the solution is as simple as that.
How is the engine running now ? After all, changing the intake spider
opened up the throttle significantly.
The engine should be run in by now to the greater power. What rpm do
you see in full throttle flight?
What is your ground speed versus airspeed?
Hartmut
