Mailing List flyrotary@lancaironline.net Message #13656
From: rijakits <rijakits@cwpanama.net>
Subject: Re: [FlyRotary] Re: DAR visit?
Date: Sat, 11 Dec 2004 18:58:28 -0500
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Message
Congratulations Paul!!
 
The more uneventful the first flight the better!! :))
 
Looking forward to your troubleshooting reports! For me that 's the most interesting part of the evolution of an Experimental, as here we all learn something to put in the notebook for our own project troubleshooting!!
 
Good luck with power problem!!
 
Thomas Jakits
----- Original Message -----
From: Paul
Sent: Saturday, December 11, 2004 6:22 PM
Subject: [FlyRotary] Re: DAR visit?

 
----- Original Message -----
Sent: Saturday, December 11, 2004 11:40 AM
Subject: [FlyRotary] Re: DAR visit?

Hi, Rusty....yep....airworthiness certificate in hand.   
 
Congrats!  
 
Not looking like the greatest choice of wind at your airport today.  I just checked the wx for the area, and find a 15kt gusting to 22kt, which is almost a direct crosswind from the left.  Should ease up this afternoon, and be much better tomorrow.  With that kind of left crosswind, coupled with my ample left torque, I'd never be able to take off :-)
 
Cheers,
Rusty (more bite than bark) 
 
You're correct, Rusty....the winds were a direct crosswind 20 knots, gusting higher (windsock standing straight out).  At approximately 3:30 P.M.  my SQ2000 slipped the surly bounds of Earth....made a couple circuits around the airport and had an uneventful (yawn) landing.  The precarious part was the take-off and climbout.  I am not getting enough power.  From 1/4 to 1/2 throttle, engine accelerates smoothly and plenty of power. As soon as I try to go above 1/2 throttle, the engine begins to bog down. Advancing the throttle more only made it bog down even more.  On takeoff roll, I was only able to get 4400 rpm's at approximately 1/2 throttle. Acceleration felt OK, and the nosewheel lifted at around 70 knots. Mains lifted off shortly afterward, but it just didn't want to climb. (Flew fine in ground effect, of course).  Unfortunately, I had reached the point of no return (short runway) and past the accelerate/stop point, so I was committed.  Found a "V" in the treeline and headed for that.  Made it...(whew)....continued slow climb to 2000 feet, made a couple of circuits around the airport and had a smooth landing (considering the strong, gusty crosswinds).  Down and stopped by mid field. 
     I had a few "bugs" to work out, like tightening the tension on the nosewheel, so after 3 trips to the runway and back to the hangar, by the time I got to the runway the fourth time, water temperatures were up to 190 degrees.  Fortunately, on climbout they started dropping, and by the time I was downwind, they were stable at 170.  I am pleased that the temperature decreased in the climb.
     I have to work on the power problem ASAP.  I'm thinking it is mixture related. I had programed the MicroTech ECU to be 10 percent leaner (for all throttle settings), and perhaps that was a mistake.  If I remember correctly, you need sufficient air and sufficient fuel to make power.  Because the butterfly in the throttlebody continues opening past 1/2 throttle, I'm reaonably certain that I am getting more air past 1/2 throttle. I am assuming that I am not getting more fuel coming in past that 1/2 throttle position, causing the engine to bog down past 1/2 throttle.  Best RPM I could obtain was 4400 rpm (in cruise with the prop unloaded), and with a 2.19:1 gear reduction,that puts my max rpm on the prop at only 2000. Barely enough to fly, let alone climb out. Will continue problem solving and pass on results.  On the positive side, first flight was successful, aircraft flew well, and no-one got hurt.  I have to count that as a success.  Take care.  Paul Conner, Mobile, AL
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