Trust, but verify.
President R. Reagan
Flight Testing Update : This page has a lot of pics, it may take a while to load................
05/01/03 Well, now that I look at the last date of entry, I see that it has been a long annual. The old Lycoming 0290 is gone and a zero timed 0290 D2 is in its place. New engine mount, new canard tips, new belly boards and the removal of about 50 pounds of stuff off the bird has taken some time. The Raptor is mostly back together and ready for testing again. The revised evator torsion tube holders are sweet and there is no play in the elevators now.
08/18/02 Lycoming is back together and running nicely so of course, we tore the plane apart and moved her back to Blue Ridge for extensive annual. The control system slop is high on the list for rework. Check back in December.
07/24/02 Tore Lycoming I0-290 apart to change out 4 cylinders. Discovered that 0-290 parts are very expensive.
07/16/02 Virtually no climb performance. Continued testing of the new aft wing install AOA. Put 40 lbs of weight back onboard and tested slow flight characteristics. At 65 mph the nose was at 12 degrees AOA. The elevators were at 3 degrees deployed with reflexors at max reflex ( upward ) position. As the canard began to stall, the rear wing slipped into the shadow of the canard and sent the rear wing into violent short period flutter. As the nose was dropped, the aft wing came out of the canard's shadow and stopped fluttering. With less reflexor dialed in (ailerons both dialed more towards neutral) the same flutter occurred but it took 8 degrees of elevator to pitch the nose up. With the reflexor dialed all the way out (ailerons deflected down) it took all 15 degrees of elevator deflection to even pitch the nose up high enough to get the canard close to stall ( which it did not). I believe the canard starts to stall at 13 degrees AOA. Engine was began over heating from all the slow flight testing and flight had to be cut short.
07/13/02 Testing of the new aft wing install AOA. Aft wing install AOA is -1.5 degrees to the canard's chord line. Takeoff can now be done at 80 mph with 10 degrees elevator deployed. Tested high angle of attack flight by pulling nose up to 12 degrees AOA and throttling back to 75 mph. No in-flight anomalies to report. Reconfigured reflexors and elevators for high speed and had aircraft up to 180 mph in sustained level flight (right past the tower). At 150 mph, the elevators are deployed only 3 or 4 degrees with reflexors trailing up about 3/8". Mostly I just wanted to have a flight to see if the engine would get hot. Ran the Lycoming at 90% plus power for 45 minutes before the oil temps went above 225 degrees F. Engine still running hot. Average fuel burn was 6 gallons per hour. Cylinder temps are 350 degrees or less throughout envelope. Climb behavior is getting weaker. Estimating 200 to 400 fpm at best. The aircraft has a very promising top end but no power to climb. Familiar scenery goes by real fast at 180 mph :_)
07/01/02 First flight of "Salt
Boy". The little guy currently weighs in at 40 lb, but will grow to
250 lbs before he is
kicked out of the cockpit. Raptor's gross wt is now checked out to 1440 lb at
station 39.25". (Dragonfly guys have to add 24" to my station
numbers due to a difference in the zero station) Weather was marginal
for testing with 10 to 15 mph cross winds again in rough air. Testing was
short but handling characteristics tended to be sluggish at 75 mph with to great
a sink rate (due to full deployment of speed brakes and not carrying
enough power).
06/31/02 Raised the aft wing's install incidence by a
degree. A very nice, old C172 just so happened to be
flying along side to get this picture. Tested out the reflexors and found
that the nose can be lowered several degrees AOA but the elevators must be
deployed to compensate for the lost lift. the increase in drag will not
allow the plane to speed up. New oil cooler position now keeps
engine cool. Landed at 75 mph and made the first turn off.
could have stayed in the air all night, but it had been a 16 hour day of
airplanes and somebody still had to fly that Cessna back home. Aircraft
is very nose heavy and requires nearly 10 degrees of elevator deflection to stay
in level flight.
06/15/02 An extended testing period allowed for right rudder testing to center the yaw string, trim and pitch work, shallow turns and initial investigation of the reflexor system. Reflexing the ailerons (1/4" down) allowed for the the AOA of the system to be changed from 6 degrees to 4 degrees and speed increased 10 mph. The new (larger) airspades worked only partly and the elevator loads are still high (restricting deployment of the elevator to less than 10 degrees). Reflexing the ailerons (upwards) allowed for higher system AOA's and a neutral loading of the elevators throughout landing cycle. The elevators remained only minimally deployed for the entire landing process. The lack of elevator deployment raised the landing speed to approximately 100 mph. This aircraft does not slow down when the engine is pulled. Approximately 25 minutes into the flight, engine instrumentation indicated oil temperature nearing the max safe operating limits, so the test was terminated.
06/08/02 High speed taxi test of new ( larger ) elevator airspades became a hop around pattern. 25 kt crosswinds proved to be too much for this aircraft. New airspades were marginally more effective. Deployed right rudder to amplify right aileron authority. Reset of aft wing (+1.0 degrees AOA) and 1/4' aileron reflexor down created too much aft wing lift and generated significant "nose down" stick loads. Aircraft needed more canard lift but was too busy with weather to try new reflexor controls. Overall, aircraft needs more aileron authority for rough winds. Take off was 80 mph, climb out 100 mph, downwind 120 mph (full power), side slipped most of final at 100 mph and touched down at 80 mph. Put massive side loading on gear on landing due to gust. Gear flexed but sustained on visible damage. Note : this aircraft is not controllable in 25 kt (gusting to 40) crosswinds.
06/02/02 Took aircraft around the the pattern today for first time. Shallow ROC (200 ft/min) but rapid airspeed increase (160 mph on downwind). Constant load (about 2 pounds) on stick from elevators wanting to cycle up most likely due to too much aft wing lift. tested out the Reflexors: cycled them upwards and nose went up. Stick forces vanished but full reverse elevators would not bring the nose back down. Cycled reflexors back down and nose came down, stick loads returned along with pitch control. conclusions : Reflexors effective as secondary pitch control but currently to sensitive. Lack of aileron authority at high RPM resulted in having to pull throttle. Low RPM restored full roll control. (note did not use rudder in these test). Take off at 85 mph (5 degrees AOA of fuselage, flew pattern at 120-140 and 5 degrees AOA (briefly dipped nose and accelerated to 160 mph) , came over fence at 100 mph, landed at 80 mph and 5 degrees AOA indicated. This aint no C172, it is a fighter plane in disguise ! ! !
06/01/02 Mistake hop into the air at end of high speed taxi test of new elevator airspades. Once airborne at 70 mph, the aircraft rotated to 15 degrees AOA and the nose did not want to come down. The rear wing reflexors were set to neutral (which set the servos at 1/2 inch above the trailing edge) It was ( later ) concluded that the rear wing was not making enough lift due to the aileron servos being reflexed), the canard over-powered the lift ratio and the rear wing nearly deep stalled. Chopping the power and mushing it down to the runway allowed for a landing (long) at very high AOA. Ailerons seem effective down to 65 mph (with no throttle). Aircraft took 2000 ft of runway to slow down 5 mph airspeed.
05/25/02 High speed taxi testing no longer a danger to airport or pilot. Having 1.2 degrees toe-in seems to have solved the taxi drift. Tightening the nose gear got rid of the shimmy. Deploying the aileron reflexors 3/8" downwards has fixed the pitch up problem of the nose on landing. Elevators still very heavy, always wanting to cycle up.
May '02 Taxi testing has us drifting all over the runway. Nose wheel shimmy, main wheel shimmy, drift, and difficulty steering the bird seems very out of character for her. Non of these handling issues were seen on grass strip at same speeds (up to 80 mph). Thinking that it may be the new crown they put on 36 last week.
April '02 Taxi testing at Oak Hill is wrapping up. There is not much more we can learn from zooming up and down this strip any more (except that this bird is ready to fly). Speeds up to 85 mph are stable (if a little noisy). Elevators are still heavy, but sanding the top surface of the canard helped.
March '02 Resuming taxi testing on grass strip with new nose gear. No flexure in new gear structure at speeds to 45 mph. the rubber donuts take a beating, but the ride is smooth. Elevators are still heavy (like there is no air over the top of them to push against the trim tab)
Jan '02 decided to take a little pause in the testing (while we make a new nose gear) and sand/prime the bottoms of the wings.
Dec '01 first short runs on grass strip. plane handles well but tends to fall on its butt when pilot gets in or out. main wheels may be wrong place
June 16, 2001 Eos Raptor is certified FAA Experimental status.
taxi testing at at Blue Ridge ( click here ) grass strip (early spring '02)
more taxi testing at at Blue Ridge ( click here ) grass strip (early spring '02)
gettin ready ( click here ) (spring '02)
yet more taxi testing (up to 45 mph) ( click here ) on grass strip (early summer '02)
canard testing at 45 mph ( click here ) basic tuft testing grass strip (early summer '02)
taxi testing at 45 mph ( click here ) on grass strip (early summer '02)
canard testing at 45 mph ( click here ) basic tuft testing (early summer '02)
taxi testing at 85 mph ( click here ) (early summer '02)
taxi testing (up to 85 mph) ( click here ) paved runway (summer '02)
totally ready for first hop ( click here ) (summer '02)
sixth hop (first photo opportunity) ( click here ) (summer '02)
07/13/02 hop (first high speed pass of field) ( click here ) (summer '02)
This page information was last updated on 05/02/03.
