Tom,

 

Verrrrry interrrrresting!

 

** It would be nice to know why the relay got stuck (contacts fused?) so that the cause can be eliminated. 

** Did you later measure the actual flap angle since it was probably larger than 45 degrees if the motor reached its mechanical limit?  Such a deployment could explain the lesser effect of the elevator. 

** Were the flap to bell crank push rods bent as the hole thru the rear spar might not have been big enough to handle such an extreme? 

** Do you trim the elevator with a tab or spring load the whole elevator?  If by tab, it might not be as effective at slower speeds.

** What do you estimate as the location of the CG (I assume you still have that heavier engine up front)?  It might be too far forward when low on fuel. 

 

Nice flying to a successful touchdown.  Timely responding to the drop in airspeed saved the day.  Power up and pushing the nose down to keep the speed up is the right recipe. 

 

I can only hope that Lancair training and practice includes slow flight when all dirtied up (full flaps and gear out) as I believe that slow regime is the most dangerous.  The controllable bandwidth of pitch and power it at its minimum.  I was impressed that you dickered with the power rather than try to instantly push the know thru the panel. I often wonder if loss of control on a go-around because of too much power applied to rapidly.

 

I don't think I ever used Lancair's relays as I obtained sealed pluggable ones with 10 amp rated contacts (high quality) from Radio Shack and their related sockets so that the relay connections did not have to be soldered and were easily replaceable.  These relays have been used thousands of times over 13 flying years (knocking on my oaken head).  

 

 

 

I thought I would share my recent flap relay failure.  Looking back on what happened I think it was an interesting experience, and how my training kicked in.

So I turn downwind and slow to below gear speed.  I drop the gear and look for flap speed.  Before I turn to base I usually add a bit of flaps.  Maybe 2 seconds worth.  After selecting flaps I found a huge change in pitch trim and a noticeable drop in airspeed.  I looked out at the flaps and found them to be fully extended.  So much that I could see straight down do the ground. (or at least it seemed like it)  Instantly I added some power with little results.  I selected flaps up with no results.  A quick look at the flap breaker sticking out explained that one.  At this point I decided to not mess with anything else in the cockpit and just fly the plane.  Probably that Skip Holm training kicking in.  It also felt like I just deployed a drag chute, as the airspeed was dropping quickly.  I came back with a couple turns on the prop and what I think was about half throttle.  During the confusion I had cut the turn from base to final and was a
bit high for the approach.  With plenty of runway left I was ok with that.  I did not want to go around, period.  I found a power setting that let me hold my current airspeed and gave me some pitch feeling back.  Being high on final I pointed the nose down and came back a bit on the power.  I have never been in a Lancair that was pointed down like this one and it didn't speed up.  Combine that with the 16 gusting to 22 headwind and I had a very slow ground speed.  It felt like I was flying a Vans RV on final. haha  Everything was feeling good so I even made a normal radio call. :)  Touchdown was very smooth, I have no idea how.  I do remember that I was full aft on the stick, or pitch up.  This is a small tail 360.  The one time I wish it was bigger.  My normal landing does not consist of full flaps, let alone the mechanical limit of the flap motor, because of the small tail.  I can not trim to a neutral stick and I am not comfortable
with the lack of pitch up.

The down flap relay stuck closed causing the flap motor to run. When this happens it cuts the limit switch out of the loop.  Yeehaww

I have ordered new relays from Lancair.  Just curious if anyone knows if the relays are the same as what came with the early 90's kit? 

Tom McNerney
www.N54SG.com

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