Sunday (today) I headed out to the airport early (like 9:30 AM) to fix the nose retract mechanism, and I also fixed the gear clamp. So, 1:00 PM rolls around, and it's time to take off for the Max. Gross Weight tests. I decided to perform the rear CG (102") MGW (2155 lb.) test first, as I should get the shortest takeoff roll, and easiest landing that way. This involved loading 460 lb. of lead into the rear seats. Uggh. It took a few hundred feet more runway to get off the ground, but it still was less than 2500 ft.
I headed west and performed the stall/accelerated stall tests (no problems and no anomalies), and then decided to head up to EEN for the landing, as the runway is 6000 ft. up there, compared to 4700 ft. at FIT. As it turns out, the landing was a total non-event - I used 110 mph until short final, and 100 mph over the numbers. Just a slight flare, and greased it on. I parked, and then moved 110 lb. of lead from the rear seats to the front seat, to put the CG right in the middle of the range (99.6" - 99.9"). This takeoff also took about 2500 ft., with rotation at about 90 mph.
The climb test(s) went well - performance was not as good as at the lower weights, but that's no surprise. It was still very good - I was getting about 500 ft/min at 8500 ft. at most speeds. The stall tests also went well, with performance about the same as at the rear CG position. A couple of landings and refuelings at EEN later, I moved another 80 lb. from the rear to the front, putting the CG at 97.5". The last takeoff wasn't substantially different from the first few - rotation seemed less different at the higher weight with different CG's than it did at the lower weight with different CG's. Same with the landings. Carrying 110 mph on final for all 2100 lb. landings worked fine, and if I had to land on a 3000 ft. runway, I could have done so. No fading of the brakes, either, at these weights or speeds.
So, these stall tests and climb tests finished up ALL the performance testing for the aircraft called out in AC90-89A. At some point I'll probably do some glide tests, but since the performance of my plane seems to match up pretty well with the COZY owner's manual, I'm not sure it's worth the effort - I can just read the numbers out of the book -).
The last test left are the rest of the flutter tests, and there are a few of you that have volunteered to speak to me about them (and I'll do so before the next set of tests).
I'm now at 30.5 hours (more than 75% done!), and I'm going to spend the next few hours flying to some smaller airports (3000 ft. runways, and 50 ft. or 75 ft. wide, like Gardner [GDM], Northampton [7B2] and Turners Falls [0B5]) to get the feel of it. A couple more trips around the FIT/IJD/PSF/EEN/FIT loop, and 40 hours will be here before I know it.
The light is at the end of the tunnel, and it's NOT an oncoming train -).
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