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Cozy MKIV - Twelfth Flight Test

Date: September 5, 2002

So I played hooky from work this afternoon (what a terrible example I am for my employees) to go to the airport. I loaded up the plane with 30 lbs. of lead in the rear nose ballast compartment, and 150 lb. of water and lead in the passenger seat. With 25 gallons of fuel, this placed the CG. at 97.5, with a weight of 1650 lb. - 1600 lb. (as fuel burns off).

I took of from Fitchburg and immediately noticed that the front of the plane seemed heavy (duh) and it took about 85 mph before it really wanted to rotate. Also, the "Strong" Pitch Trim system was bottomed out, and could not keep the plane trimmed with the CG so far forward - I had to fly the whole day with a bit (not much, but some) back pressure on the stick. I believe that if I move the actuator forward about an inch or so, this should take care of the issue.

I also think that a heavier spring in the trim system could help, with this and general longitudinal static stability issues as well.  I may investigate this also.

If moving the actuator forward does NOT allow trimming to 80 mph at full forward CG, I'll have to investigate increasing the incidence angle of the canard (uugghhh).

Anyway, I started the first climb, and noticed that the plane felt anemic. Got to 8500 ft., descended, and started a climb at 120 mph. Got about halfway up (maybe 4500 ft.) and figured out the anemia - I had forgotten to retract the nose gear. Dope. Descended to 3500 ft., did the stall tests at all the bank angles, and generally found the speeds to be about 5 mph faster than at mid-CG.

So, back down to 1200 ft., pull up the gear, and start again at 130 mph. Ahhh, that's better. Up to 8500 ft., back down and land to get gas. Hey, there's another thing that's pretty different at forward CG - it won't flare on the landing. Bang - pretty good carrier landing, but without the hook. OK, remember to use slightly more speed, and just a bit of throttle just before touching down next time.

Back up, do the 120 mph, 100 mph, and 90 mph runs (with the gear up). Landed (using the new technique, which worked pretty well and still allowed a short turnoff) to get gas, but they closed the pump at 5 PM! Oh well, only used 5 gallons on the last flight, so I went up for the last time for the 110 mph and 80 mph runs. Landed and put the plane away, after another 2.6 hours in the air.

I visited a friend who's a packrat, and collected about 400 lb. of lead lumps to use for ballast in the 1900 lb. and 2100 lb. runs, hopefully this weekend.

Tomorrow, the 1650 lb. aft CG runs.

There's no Protocol for this flight - see Flight Test Protocol 10.

End Date: September 5, 2002

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Copyright 2002, All Rights Reserved, Marc J. Zeitlin