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Wheelpants Mounting and Tests

Date: July 12, 2003

So the weather this morning was crappy (no visibility and 200 ft. ceilings), so I had to wait a couple of hours for it to clear so that I could fly over to Orange airport (ORE) to get some pancakes at their EAA chapter fly-in, courtesy of John Vance. At around 930, it cleared, so I headed out to the airport to meet Andrew Johnson (a prospective COZY builder) to try to salvage a breakfast trip -). We got over to OREjust in time to get the last two plates of food, but not in time for the homebuilt judging (which was just as well, since Al Dean's Glastar was there, and it's a beauty, and he won -) ).

At any rate, Andrew seemed pleased with the plane, and we got about 40 minutes in there and back.

The real work for the day was threefold - first, add a couple quarts of oil, second, apply the vinyl 15 inch tall "83" Airventure Cup Race #'s to the bottom of the fuselage just in front of the landing brake, and last, mount the (unpainted) wheel pants to check them out for vibration, fit, takeoff and landing performance and speed enhancement.

The pants mounted easily and leave about 2" of tire showing, with about 1" of ground clearance with the nose down. They seemed pretty rigidly mounted, so I took off and climbed up to 9500 ft. to get above the clouds into calm air. I didn't really notice much of a difference in climb, which is about right, since I was climbing at about 110 mph IAS, so I figure that maybe the pants make a 50 fpm difference, which I certainly can't discern.

I reduced the throttle and leveled off at about 140 mph IAS. No vibration, no problem. I slowly increased the throttle, letting the IAS build slowly so that if there was I problem, it wouldn't get away from me. At 9500 ft. and 46 F or so, I used to get about 189 mph - 191 mph TAS (according to the GPS). This time, the IAS built up to about 174 mph, and the GPS was telling me that my TAS was about 204 mph! A few people (Ken Brimmer for one) had told me to expect about 10 mph increase with the wheel pants - it looks like I've got that beat by a few mph!

This was only one test and not an extensive one by any means - I only leveled out for about 2 minutes. Tomorrow will be a better test, as I'll be flying for an hour from FIT to CDW to get my son to his grandparents. However, I'm VERY pleased - that's a BIG difference.

On the way down from 9500 ft., I increased the IAS to 200 mph (still not comfortable with IAS higher than that) and there was no vibration whatsoever. Landing was fine - no scraping or tire touching. Just have to paint them now.....

AC Race, here I come! -).


I flew down to NJ from MA to drop off my son today - 2.1 hours total round trip. I flew at 6500 ft. and 8500 ft. on the way there, and 7500 ft. and 9500 ft. on the way back (had to climb over some clouds). In all cases, I let the speed stabilize and then asked the GPS for TAS. Max. TAS was 210 mph at 6500 and 7500 ft., with density altitudes of 7000 and 8000 ft respectively. This was full throttle, leaned to just rich of peak. At 9500 ft. I was still truing out at about 206 mph. I believe that all these #'s are close to 15 mph higher than before the pants - it's just unbelievable - I was expecting 7 - 10 max.

I haven't tried a top speed run down low - it's been just too bumpy and I don't like having my teeth hammered out of my head, but it looks like I'll be dang close to 215 - 220 mph. Yee hah.


One thing I forgot to mention about yesterday's flight with the wheel pants was that I removed them after the flight to take them home to paint. In doing this, I felt around to see what the heat distribution within the wheel area was. I tend to use the brakes a lot, both on landing and taxi, so they get pretty warm.

The MATCO brake discs and cylinders were hot - not so hot that I couldn't touch them, but VERY warm. The wheel itself was very warm, and the 1/8" aluminum heat shield was pretty warm as well. I have wrapped the bottom of the gear leg with fiberfrax and aluminum tape, and the tape and gear leg were at ambient temperature. It's impossible for me to believe that I can ever do any damage to my gear legs given the protection that I've got, even though my wheel pants are not vented.

One data point - draw your graphs as you see fit -).


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