This weekend I too the time to disassemble my mono gear which had been
assembled a few years ago. I took some measurements.
Using feeler gauges, one Port swing arm was .055" away from seating when the
Starboard leg was against the stop. Doing the Trig, after grinding this
down to equal seating, this provided .8 degree improvement in Over Center
condition.
Allowing for the taper of approximately 4 degrees in the swing arm,
measuring with a balance protractor against the arm and then the shock
absorber - hanging straight down, the over center condition is now 2.31
degrees. I have not measured yet with the gear reattached, but assume this
will improve slightly.
The corollary of the above is that the original position before grinding was
1.51 degrees. This is virtually nothing.
Studying the design, if the shock absorbers were not dampening well in the
reverse direction, a smack of the wheel against the ground and bounce up,
would allow the rubber block to snap the gear down quickly, and pop out the
over center of 1.5 degrees if there were any slop or bending in the gear
retraction lever. This is particularly worrisome, as how does one check the
performance of the shocks - pull down on the prop in the same way you check
a tri-gear's oleo? I know it's working for a lot of people, and has the
blessing of the PFA, but it sure seems marginal.
I am considering locking the gear down, (which will also improve
insurability) which is easily done in a variety of ways. Fairing this in
would be fairly easy with a large shapely fibreglass cover. I would then
operate the flaps and outriggers separately. Has anyone done this?
I guess no one knows what the speed penalty is if the gear is left down in
cruise! (Unless you cruise around with the flaps down all the time!)
Cleve Lee
A198 now in Market Harborough
... and finally getting back at it . .
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