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Robert,
I think the only one
"assuming" anything here is you!
In your first post regarding
me exceeding Vne, your comments were rude and insulting.
You claim "I'm dangerous, you
hope I never fly over your house, I should never take passengers".... "YOU will
foot the bill for my insurance claim"....
You don't me, you've never
seen my aircraft, you have no idea my experience, abilities, ratings, degrees,
anything!
I never said you didn't have
knowledge, I just said you have no experience with Lancair's. You have no basis
for your claims. You have no statistics what so ever.
All your statements and
assumptions from a man that still has his kit in the garage?? That's my
point.
A productive forum discussion
regarding the various aspects of Lancair's is more then welcome, there's a
wealth of knowledge here, but blindly insulting another builder / pilot, when
you yourself have not done your research, is not productive at all.
The stats are: Not one LNC-2
has come apart from exceeding Vne. There are no service bulletins from Lancair
regarding high speed flutter on a small tail LNC-2.
I'm not on this forum to
insult builders / pilots. I'm here to share in the wealth of knowledge and
experience. Each person can take what they want from it. Some learn, some
dispute, some read from the sidelines, some contribute and some just laugh.
It's all for a common cause.
Randy
Stuart
LNC-2
----- Original Message -----
Sent: Wednesday, December 02, 2009 6:39
AM
Subject: [LML] Re: Vne is NOT a
meaningless number
Well, I certainly ignited a firestorm! Good. Getting people
talking is a good thing.
Randy is right in one respect -- as builders of an airplane we are
entitled to set whatever limits we want, as we are legally the
manufacturer. I'm also pleased that his loyal passenger paints a picture
of an otherwise very cautious pilot. I still won't fly with him, but
then, it's hardly likely that an invitation would be forthcoming, eh?
However, as I tried to say before, there many factors which influence the
selection of a never exceed speed. Sometimes it is flutter (that's a
for-real, don't-screw-with-this limit, but does not appear to be the limiting
factor on the 320/360 airframe), sometimes it is loading imposed by an
FAA-specified gust (that's a somewhat artificial limit because there is no
guarantee that you'll see that gust -- you might get more or you might get
less), sometimes it is loading imposed by a fully deflected aileron at Vne (if
that's the case then you might go faster safely if the controls are not fully
deflected), sometimes it's a stability or controllability issue caused by
Mach-induced center-of-pressure shift (not gonna happen on an LNC2, but it
might on an LNC4). And those are just the more common reasons why a
particular Vne speed might be chosen.
Certified airplane manufaturers have to prove to the FAA that the vehicle
is safe in all respects up to Vne. Experimental aircraft
are not subject to these constraints -- we can pull numbers from wherever we
choose in order to set our placard limits. Myself, I have simply assumed
that Lance and company used a methodology similar to that used by certified
airplane manufacturers in establishing their placard limits. I suspect
that they actually used the identical methods, but were not obligated to prove
it with FAA-approved and DER-witnessed analyses and tests. No, I don't
know that for sure. In that respect, no, I have not done any research to
convince myself that the Lancair factory limits are safe, either. But
Lancairs have not been breaking up in flight with any regularity (except in
thunderstoms) so the established limits, which most pilots observe, are
probably okay.
I think it is interesting that Randy and his loyal passenger have assumed
that I don't know what I'm talking about simply because my Lancair is not yet
flying. In fact, it is not complete because I was way too busy for
several years as a professional aircraft designer, serving as Chief Engineer
on an aircraft that was to be certified under FAR Part 23, and later teaching
a class on designing aircraft so that they may become certified.
And yes, conducting structural loading tests on wings, fuselages, and vertical
tails. Aircraft engineering is what I do for a living --
building them in my garage is what I do for a hobby. But this is not a
"mine is bigger than yours" contest, so I'll stop there.
Jeff Edwards has suggested that I prepare a posting fully explaining how
Vne is determined. He said, and I agree, that many people reading this
list would enjoy an educational posting of this nature. Someday I may do
that, but it's not a short subject and I don't have time right now.
Consider that a cop-out if you must.
Fly safe.
- Rob Wolf
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