I thought this one was worth passing on to the Forum - for those unfamiliar
it's from the very useful aero-electrics list that Matronics run, and Bob
Nuckolls is the highly-respected guru on it.
It sounds like a candidate for a future Darwin Award...
Regards,
Jeremy
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
L. Nuckolls, III
Subject: AeroElectric-List: Some airplanes were never ment to fly . . .
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
<bob.nuckolls@cox.net>
Just got this note from a friend of mine who was
inadvertently sucked into helping resolve a few
assembly issues on an amateur built airplane.
Seems the builder was offered one of our OV
modules but a supposedly learned friend decided
he knew how it was supposed to work without
reading the instructions.
After the alternator ran away and smoked some
electro-whizzies in spite of OV "protection",
my friend finds himself paddling upstream in
the rapids of ignorance with a very short paddle . . .
>The builder is making a GlassStar which is now in flyable condition. Big
>engine. His "friend" helped him rig the throttle cable. At first turn
>over of the engine, it went to full power, ~2900 rpm on a 3 blade
>prop. Pulling the throttle all the way out reduced the rpm about 300. I
>pointed out the problem, a lever "mechanical advantage" on the carb where
>the cable connects. Limited delta length of the "wire", I suggested move
>the attach point further in toward the carb to get greater "range". There
>was an argument with the "friend".
>
>A friend of mine spent some time with the builder. His "friend" had
>rigged the ailerons so that the "cross over" cable was wound around the
>"outgoing" cable, in each wing, two turns each side. Further, the flaps
>cable was wound around that. Somehow, it passed FAA inspection that
>way. You could put the stick anywhere you wanted, and it would stay
>there, with a real high "break loose" force. All of that got straightened
>out over 3 days of restringing by my friend.
>
>I was called in to look at the ELT installation. There was a dashboard
>remote switch of the "pull and toggle" variety. Can't change the position
>unless you pull out on the "flipper" - prevents accidental actuation on
>the remote dashboard switch. It was working in the ON-ON method. Pulled
>the switch and noticed that a terminal had been pulled out of the switch
>on the wiring side under the dash. Missing a terminal, it was just wired,
>for that wire, to the other side (throw). The builder's "friend" had
>checked it out for him, and rewired it; the builder said. I rewired the
>switch, so there was an OFF, regardless of the ELT "impact switch", and an
>ON, regardless of the ELT "impact switch", as well as the center "what
>ever the ELT impact switch wants".
>
>The builder has your files, which I gave him on a disk, my schematic, and
>your phone number and your e-mail address. He said that he gave them all
>to his "friend", and that the "friend" rewired your OV protection
>circuit. He said that there is now a third contactor. He didn't want me
>to look at it, even though I volunteered. He said that he isn't going to
>contact you.?!
>
>I have told my friend what I saw, he related the story of the re-rigging
>of the flight controls, and suggested that we both stop helping this
>fellow, because there might be implications during an inquiry that is
>likely in the future.
I was just going to suggest that approach. Some airplanes
were just not meant to fly and this may indeed be one of
them. I think I'd distance myself as far as possible from
this accident looking for someplace to happen . . .
>I really have to stop helping people.
Don't let this one event discourage you. The only
thing sadder than good information not shared is
good information being ignored. The bell-curve is
a fact of nature . . . SOMEBODY has a natural
obligation to occupy the lowliest places on the curve.
Fortunately most are eliminated from the gene-pool
at minimum risk to others.
I think it was Igor Sikorsky who was credited with
the following observation: "Most early designers
of airplanes were also the test pilots. This had
the beneficial effect of eliminating bad designers".
>Meanwhile, the abstract of my next paper (European GNSS 2003 at Graz
>Austria) is on the web at
>http://www.gtwn.net/~keith.peshak/GNSS2003.htm I sent a copy to the new
>FAA Administrator and the Transportation Secretary. I guess I am getting
>a little frustrated.
Understand. I'm just wrapping up a 4-year effort trying
to fix a $10 problem in a pitch trim actuator that
has cost us 10-15 million dollars in warranty claims
and untold damage in customer dissatisfaction.
The problem has gone on for so long and cost so much
money that nobody wants to admit that there was ever
a simple solution. Hence, we're about to embark on
a development program for a fine new actuator
that will cost twice as much (but last the lifetime
of the airplane), needs perhaps a $million$
more in development costs and will take two years to get
to the field. In the mean time, customers who bought
our airplanes in good faith are still getting screwed.
When you're dealing with professional bureaucrats,
consumer benefits and faith in the logical application
of physics are the smallest of driving forces
on their considerations. Doesn't matter if it's
government or business.
All we can do is be good engineers and don't
rewrite any laws of physics. If our audience
is high enough on the bell curve to perceive
the value of what we do, great. You may have to
bang on the bell a whole lot before you get
the attention of folks in top 10% of the curve.
Bob . . .
http://www.matronics.com/browselist/aeroelectric-list
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