Submitted by Bill Kramer, Glasair III builder.
During recent gear cycle tests, I discovered a problem. The gear would retract but would not extend. After much investigation I discovered that several small pieces of rubber material from the process of my assembly of the flexible hydraulic hoses had lodged themselves in the “B” cross and up against the small hole in the snubber fitting. The debris allowed near normal “up” pressure allowing the gear to retract, but kept the oil from flowing back to the pump for the “extend” cycle.
This situation represents the worst case scenario if it would have happened in the air. Not only could I not have gotten the gear down with the normal pump, using the emergency pump would not have done any good either’.
I thought I had taken great pains to clear out the lines prior to starting tests. I can only emphasize the absolute importance to builders of flushing out these lines several times before flying.
