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Good afternoon everyone !!!!
What cruising speed are you getting with the CH-750 equipped with Continental O-200 ???
I haven't gotten more than 85 miles without slats.
Thank you very much !!!!
Hi Paulo, Lots of variables come into play here as you know. I have not tried flying without slats but I typically cruise around a TAS of 84mph at 3000', IAS is around 78 to 81mph, I'm also running with smaller 5" cruzer tires. With my current prop pitch on my o-200 I have to turn 2600rpm with 24" of manifold pressure to get close to 75% power at 3000'. It's hard to know exactly what %HP you are running without a MP gauge, but you'll likely have to turn higher than 2500 rpm at that altitude to get 75%. According to the manual o-200's seem to have to spin pretty fast to make anything close to published values. Calculating your TAS from your IAS and running a bit higher rpm you might find you are closer to 91o 93mph TAS without slats, but I would not expect much more than that. Speed is kind of an up hill battle with a 750 STOL, I choose to ignore the ASI and just enjoy the outside view. :) one other thing to check is your flaperon rigging, mine were rigged slightly to far "up" originally. I had found in flight "bumping" the flap switch down allowed me to cruise 2-3 mph IAS faster for the same power setting (had to re-trim the elevator slightly), this did not move the flaperons much, maybe 6-8mm down measured at the trailing edge, but it did seem to give a positive increase. Good luck and happy flying!
Good afternoon Clint !!!
I'm also on the smaller 5" tires.
I also set my flaprons higher than the Zenith design.
I'm flying with a maximum RPM of 2500, as per the O-200 manual.
Our numbers seem pretty close, except that I'm without the slats.
Thank you very much for the information !!!!
Good flights !!!
Speed is kind of an up hill battle with a 750 STOL, I choose to ignore the ASI and just enjoy the outside view. :)
Clint got it right: "It's the journey, not the destination."
Or, more specifically in reference to speed: "When it come to a STOL 750, think Jeep and not Ferrari."
Tuche(two shay) my poor French!
I have a CH 750 STOL and a CH 750 Cruzer, both powered by a Continental O-200A. The STOL cruises at 85 MPH at 2400 RPM. The Cruzer cruises at 100 MPH at 2400 RPM.