Avstar Aircraft of Washington, Inc.

10415 172nd St. E., Hangar A1
Puyallup, WA  98374
office (253)770-9964
or (253)770-0120
email:  avstarair@att.net

01-25-2012 Ask Mike! Question
Gear Won't Go Down Unless You Crank It Down

Mike,

We have a customer that has a Beech Baron B-55 that we just did the Annual on.  The gear and everything checked out good on jacks.  First flight out of town, he has reported that the gear will only go up and not down, unless you crank it down!  I had a mechanic put it on jacks and he verified that this is the case.  He checked to see if there was any obvious damage like broken wires, etc...and that all switches were mating & clicking.  Do you have any suggestions where we should start first when it arrives back to my shop?  I'm thinking maybe the reverse relay, since it goes up fine, but will not come down?

Thx,
Robert

Possibilities that that strike me, in order of likelihood, would be hung brush in motor, broken wire/corrosion on down limit switch contact, then relay.  The relay seldom is an issue, motor is more likely.  When electrically troubleshooting, you will have voltage on the red wire when you want the gear motor running towards down, so check that when on jacks.  Naturally, have the spar cover off and access the relay from the rear, not the top, while power is applied, just in case the gear motor takes off.  As you are aware, the 24 volt gear is very fast - you don't want your hand/arm in the wrong place.

Let me know what you find.

Mike