At 10:59 PM 11/06/2009, you wrote:
Mike,( I always like your posts, don't take offence out of hand!)
Firstly,
I don't understand your point, but I would like to thank you for the time
you spent putting it forward.
Typing is such a dreary, half baked way of communication.
Wayne,
The point was that a satisfactory engineering device whose
characteristics were known was unable to continue to be used because
of an arbitrary bureaucratic rule that the manufacturer had to
"certify" it. The bureaucrats could have simply decided that for
motorgliders "uncertified" engines could be used as they continue to
be in ultralights. The result was that a whole new set of problems on
devices of unknown service history was created resulting in
unnecessary expense and hazard to owners.(better the devil you know
etc). These devices weren't even going to be better technology - just
the same old 2 stroke boat anchors with horrible reduction drives and
retraction mechanisms.
Secong,
What, ultimately is the answer, or an answer, or could be improved?
I have a deal of experience in manufacturing machinery and I could not fit a
batch of doors to a helo that would all be the same, I don't know of anyone
who could. The parameters are too flexible.
I guarantee the door made for the frame would not fit in Alaska, and if it
did, it would not fit in 3 months of helo use in Hawaii, simple engineering
problem, currently no satisfactory all purpose fix.
The current answer is, unfortunately, build it substandard.
For a door that would mean the thing is overweight and loose fitting.
For an engine?
The problem with the helo doors wasn't that they didn't fit the hole
in the side of the aircraft, it was that when they locate the hinges
and latches they don't seem to use jigs.
Modern engines for cars are built way better than that. There's a
story about the early days of WW2 when Ford at Dagenham were asked if
they could build Roll-Royce Merlins. They agreed to look at the
drawings and after 3 weeks rang Rolls and said we can't do it. The
Rolls guys said "tolerances too fine for you, eh?" The answer " no we
can't build crap that badly. ALL our pistons have to fit ALL our
cylinder bores - we can't hand select."
This is all a factor of production numbers. Sports aircraft including
gliders are made in such small numbers and have little potential to
kill more than one or two people at a time, overwhelmingly the
occupant(s). What is the point of certification particularly when you
"certify" a prototype. This prevents timely introduction of bettter
parts, design and technology.
If I were to build an engine to power an aircraft (my dream aircraft
perhaps) it would be about 2/3 the size of today's current crop and have
about twice the output. Perfectly possible with todays standards.
No problem at all, really.
:-)
Ask the guys trying to use car engines in homebuilts. Possible, but a
minefield. See May 2009 Kitplanes for details.
Lycoming and Continental are doing fine thank you. Add modern fuel
injection and ignition systems and you won't do much better - for long anyway.
Mike
Borgelt Instruments - manufacturers of quality soaring instruments since 1978
phone Int'l + 61 746 355784
fax Int'l + 61 746 358796
cellphone Int'l + 61 428 355784
email: [email protected]
website: www.borgeltinstruments.com
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