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To Ed de Chazal, when you answered Angier Ames re: gear pressure bleed

-down, I don't think Angier was talking about bleed-down while

retracted. Instead, I think some of the Glasair Gang has been spooking

him about the bad things that will happen when, not if, his hydro

pressure bleeds down while the gear is extended and on the ground.

To that, with a Lancair, the answer is "Nada" - but not for a Glasair.

They use hydro pressure to down-lock so if it ever goes away, the

gear will collapse. I speak from eye-ball evidence of the guy in the

hangar next to me - last year he had a hydro failure in his Glasair

III, following which I honestly believe his prop was just a bit too

short to be useful.



As you know, when the gear is up, it is held up by hydro pressure.

For you folks that haven't flown yet, or are just getting

started, there is an exciting little happening that you WILL

experience sooner or later. One that no one has probably thought to

tell you about yet. This *fun* thing will happen at an unexpected

moment while you are happily droning along being pretty smug about

things. Just when you're at your most relaxed, all the electrical

stuff on the panel goes "TWITCH!" accompanied by a subliminal "GRUNT!"

 - GUARANTEED to get your attention and your heart rate up six

or seven zillion beats! Depending on a lot of variables in a system

that must have some leakage, the up-lock pressure can bleed down

enough to let the high-pressure limit switch kick in for just a pulse

when it will immediately turn itself off again.



The pump starting up, particularly into an already high pressure,

guarantees that it will pull a big current pulse and the results will

definitely get your attention! Hence the TWITCH! and GRUNT! In my

plane, while on cruise, I'd see it about every 35-45 minutes. (That

frequency was likely due to a sightly higher than normal high pressure

(up-side) leakage rate - around the threads of the junky, brass, gear

dump-valve that came with the kit [subsequently replaced with a high

quality valve]). Until I figured out what the H--- was going on, I

must say, I was a little spooked!



Not being too bright, I took the wife with me on a 2 1/2 hour flight

before I had figured out what was going on. The "TWITCH!" and "GRUNT!"

did not escape her notice. As she's still of a mind that *real*

airplanes are only entered from a carpeted walk directly from the

first class lounge - and anything that happened on my little buzz-bomb

that was in any way unusual (meaning that I turned white and sweated

when it happened) was a BAD THING. Funny how the wife's insistance

that I get her on the ground *now!* forces one to really think. Also

fortunately, I had caught the "Gear in transit" light flash at the

same time as the TWITCH! 'n GRUNT! and I had the proverbial light

flash over my head at the same time, and I figured it out. Not a

moment too soon too! I really think she believed me when I casually

turned and said "Oh! Don't worry about the TWITCH! 'n GRUNT!, that's

just a 'normal little thing', keeps the gear tightly retracted so we

don't slow down too much, and it's going to happen about every 35-40

minutes". Since she didn't insist again that we land immediately, and

the TWITCH! 'n GRUNT! happened right on schedule 38 minutes later, I

got away with one. Of course, now that I've replaced the junky valve

with one that doesn't leak much at all, the T 'n G occurs only about

once in a four hour flight, if that. Now the wife wants to know why

the T 'n G isn't happening any more and worries about it. Can't win!



Dan Schaefer

N235SP





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