samparfitt
Posts: 1839
Joined: 9/1/2002
From: West Chester, OH, USA
Status: offline
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Mike,
I used the included wood in the box for the non-retracting wire struts. I cut the hardwood pieces in half for use on both sides of the retract base. I made it a fraction higher than the height of the retract mechanism so it wouldn't hit the original flat mounting ply in the nose. I'm using 14X7 3-blade master airscrew and they only clear about 1 to 1 1/2".
Sunday's flying was good for getting the 'bugs' out of the plane: Broke the engines in at the field. One OS #8 glow(came with the engine) went South after about 15 minutes run. I put #3's in both of them. I've done this in my other OS .91's and they work good. With the engines inverted, I had to turn the low-end in about 1/4 turn to lean it out: was sputtering going from low idle to full throttle (about normal for inverted OS engines). High end was at 3 3/4 turns open.
Getting about 9800 RPM's with the 3 blades and Wildcat Premium 15/16 fuel.
I didn't put the brass tabs on my 1/8" brass rods because I thought they would stay in place: wrong! They vibrated straight up. Made about 1/2" long tabs with 2 holes: soldered one hole to the brass rod and put a screw through the other and into the wing. Also, the hatches I made were lifting up due to the amount of air created by the props when it was sitting on the ground. The wire spring in one of the hinges couldn't hold them down. Didn't have time to make sprung latches so I just used a screw to hold them shut (enough room between the gap of the hatch and fuse shield to put a screw in).
Also, about 4 of the button screws came out that held the upper boom shields on. These were the back screws where it feels pretty soft where the
the screws went in. A little AC fixed that.
After fixing all those 'bugs', I went out Monday evening for the first flight. No cowling or spinners for the first few flights so I can adjust the engines.
In order to do the vertical test, I had to have someone else put full throttle on the engines, AFTER I held it vertical. The plane's so big and those two OS .91's engines are so powerful that it would be difficult to lift it and rotate it vertically by myself if the engines were at full throttle.
Kept the high end at 3 3/4 turns for flying.
Did the vertical test in the pits and on the runway. Lined her up and took off. The left wing dropped some: not sure if that was due to all the tork or maybe not quit up to flying speed. Put the retracts up on the first down turn so I could trim her correctly.
Needed about 7 clicks right on the ailerons and 7 on the down elevator and 2 right on the rudder.
I kept giving it extra right clicks on the elevator thinking it was off but after a couple laps, I noticed that the plane was sliding left.
Looks like the tork in the engines are so great that she goes left so I put 2 clicks right in the rudder to compensate for it.
Flew her about 5 mistakes high for about 5 laps.
Then, did some lower pass bys (about 20').
Put the retracts down and didn't use the flaps.
Idle'd to about 1/2 throttle on the down turn.
Throttled down a little more just before the runway and when she was about 4' above the runway, I throttled back to idle: she dropped quickly (about 30 degrees). Came down hard enough to knock off all 3 wheel covers on the Robart wheels. One half clip came off one of the oleo pins so that was it for flying for that night.
No damage to the plane. Those oleos took all the shock. I had the throttle trim set about 4 clicks below center. Next time, I'll set it about 5 clicks above center.
She glides like a jet: come in fast, no floating this baby in.
Fixed her up last night and ready again for tonight.
I adjusted the clevis's so I can center all the trims and one of the elevator brass clevis's snapped at the base. Metal seems a little brittle. Put a nylon one on.
Also, I had one engiine sputtering (on the ground).
After shutting it down, it was smoking. I noticed brown burn marks around the cylinder head. The head screws came loose about an 1/8 turn. One of the things I do with a new engine is tighten all the screws before using it. I guess the heat expansion worked them loose. Engine ran good again after tightening the screws back up. The other one also needed tightening.
< Message edited by samparfitt -- Jul 15 2003 10:20AM >
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G. Samuel Parfitt
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