I have gotten a lot done on my Bede BD-4C airplane over the last few weeks. I adjusted the length of the push-pull tubes for the horizontal stabilator so that when the control sticks were pushed fully forward
the horizontal stabilator was angled down at least 15°. Here is a photo of the stabilator pivot showing down 16.40°.
Then I assured that when the sticks were pulled fully aft
the stabilator was up at least 6°, like this
Then I proudly surveyed my work, double-checked the plans, and discovered that I should have had at least 15° up and 6° down, not vice versa. Sheee-it!
I tried to readjust the push-pull tubes and found that I could not get 15° up without the stick pulled back into my stomach. In other words, the push-pull tubes were about one inch too short. Sheee-it again!
Fortunately, there is a “rod end” in one of the push-pull tubes that is a block of wood with .063 aluminum cladding on both sides. It was a simple matter to fabricate a new one, slightly longer than the original. Here is the result, being test fit into place.
With the new part in place, my BD-4C now has 17° up and 7.5° down, which exceeds the specifications for least 15° up and 6° down.
I took a careful pass through the aileron cable assemblies and the stabilator push-pull tube assemblies, assuring that every bolt had either a lock nut or a castellated nut. Then I installed cotter pins in all of the castellated nuts.
Next job: attaching the rudder to the vertical stabilizer. (The rudder is the part that wiggles. The vertical stabilizer is the fin that sticks up and does not move.) Here I am with the rudder clecoed together and temporarily clamped to the vertical stabilizer of my BD-4C.
Do I look happy, or what?
Jim Hann says
Art, better now than having a tech counselor or DAR find it at the airport! Looking good.
Gale says
It seems like your measurement worked that . I would verify the numbers when the stabilizer in attached. I’ve net seenit done the way you did it. Could be OK??
Gale
Art Zemon says
I will definitely confirm the measurements after attaching thee stabilator. I have plenty of travel in the Heim rod end so I ought to be able to adjust as needed.