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Permalink Reply by Clint L Gosch on January 5, 2022 at 8:17pm

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!

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Permalink Reply by Paulo Pagamissi on January 6, 2022 at 11:31am

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 !!!

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Permalink Reply by John Austin on January 7, 2022 at 9:28am

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."

John

N750A

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Permalink Reply by Norm Neuls on January 8, 2022 at 11:32am

Tuche(two shay) my poor French!

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Permalink Reply by Timothy Sparks on September 18, 2022 at 7:33pm

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.

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