Ultralight Incident report
A ultralight pilot is doing a preflight on his aircraft prior to a flight. On
inspection of control systems, he finds that the ailerons are not working properly.
Further investigation revealed that the teleflex cable running from his joy stick to the
aileron mixing bell crank has broken off at the end of the threads, a the point of
attachment.
Another pilot on the field is also inspecting his aircraft and finds that his rudder
has been damaged. The fabric has a puncture mark, which matches up exactly with his
elevator horn. After watching their aircraft, on a very windy day the pilots found that
both the rudder, and ailerons moved around, very rapidly and forcefully when the wind
gusted, or changed direction. This lead to the rudder puncturing the elevator horn and the
breaking of the teleflex cable.
Suggestions:
A simple remedy that has been found to work effectively is to immobilize the rudder,
elevator and ailerons. This can be done very easily on the rudder and elevator by the
building a set of stops.
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Tools required
Drill
Drill bit
Wrenches
Parts required
4 pieces of 1 inch tubing, plastic, wood, whatever.
2 pieces of foam insulation, used on copper water pipe
Bolts, nuts and washers
2 pieces of 1/2 inch plywood 6" x 12"
Procedure
Drill a vertical, about 1/2 an inch from the end of the tubes, if necessary debur the
holes. Place the foam insulation over the tubes. Install a bolt, into one end of one tube,
then through the same end of the other tube. Install a nut onto to bolt.
Slide the tubes over the horizontal stabilizer and elevator. Install the other bolt
into the other end of the top tube, and then the bottom tube, install the nut. Snug up
both nuts.
Build another set of stops and use them to go over the vertical fin and rudder. For
ailerons stops, take 2 pieces of 1/2 inch plywood measuring 6 inches by 12 inches. Use
glue to cover them with a non abrasive carpet material. Drill 2 holes in the centre of the
wood, about 4 inches from either end.
Install the one half of the stop, so that it overlaps both the top of wing and the
aileron the, make sure the carpet side is facing the wing and aileron surface. Install the
other half of the stop with the carpet side toward the underside of the wing, underneath
the top stop. Install two bolts through, the predrilled holes. Make sure bolts go through
gap seal area, between aileron and wing. Install nuts and snug the nuts up. There, about
30 minutes worth of work and 10 bucks worth of material, might just save your life.
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