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Rob,
May I offer some distinctions
regarding a few terms you used, which should clarify how this Lancair safety
problem should be approached?
You said: 1) Poor behavior at high angles of attack is a design
problem, and one of the risks that we accept (knowingly or unknowingly) when we
buy an experimental airplane rather than a Part 23 certified
airplane.
First, do NOT accept design
problems. When we buy a Kit, we don't buy, and cannot legally buy, an
Experimental 'kitplane'. Unless it has already been built and received its
first Airworthiness Certificate, the kit is just part materials for a
project. The magic that turns a 'project' into an 'aircraft' is the first
Airworthiness Certificate. A Kit is not different from a bunch of parts
bought or scroun ged by a plans-builder. Further, a kit of
parts legally must not constitute more than 49% of the project. And
the majority of kits are never completed to become an FAA defined
'airplane'.
This distinction is very
important to States with Aircraft Use Tax. So, please call your project a
project, and if you bought a kit to speed completion, call it a merchandise
kit. When you get your Airworthiness Certificate, the FAA says you will
become the 'manufacturer/builder' as of that date, of an 'airplane'. When
as manufacturer you sell the 'airplane', the buyer will have to pay the tax
... sales, or use. You will have paid tax opn the parts and matgerials you
bought to build the project which may or may not ever be completed into an
'airplane' ... and most are not.
As an amateur-builder you are
permitted and even encouraged to improve the design, within your own
abilities. One should not 'accept' the faults in a design and try to live
(and die) with them.
You mentioned: Remember when the Columbia crashed during spin
testing? That wasn't because of a failed spin chute -- it was because of
an unrecoverable spin mode. And then we have the Piper Traumahawk, which
obtained certification on one airframe, but produced an ever-so-slightly
different airplane which had significantly different stall recovery
characteristics (although this is the exception rather than the rule in the
certified world.)
This is not quite correct, as
any aerodynamic or primary structural change invalidates the manufactured
aircraft's FAA-granted Type Certificate, and requires re-testing for FAA
approval. This does not apply to amateur-builders or the
commercial 'manufacturer' prior to the award of the first
Airworthiness Certificate. So, when youo flight test your plane, be
looking for problems, and expect to correct them.
Your also said: Certified airplanes are usually safer at high angles
of attack,
Apart from aerobatic categoty, most 'certified' (you mean non-experimental)
are not safer at high AOAs, and are all placarded against intentional
spins. For FAR 23 they only have to demonstrate to the FAA recovery
from an 'incipient spinb', that is., the first two turns of spin-entry, during
which phase most airplanes will self-recover or unstall once... as I
recall. Most Standard Category TCd aircraft will not recover from a
developed spin at their aft CG. I think probably the much safer spin
recovery requirement of the per-WWII designs was removed after the war. ..
recovery, hand-off, from a six-turn spin.
I never understood the 'placard' approach to safety... as it ignores the
inadvertant stall/spin
Most pilots are not airplane
designers, and so that's why they don't talk about correcting design problems...
but they should be trying to learn how to correct design problems if
they're building an Experimental.
Others will have a different
viewpoint, to which they are entitled. I'd enjoy hearing
them.
Mine comes from designing,
building, and test-flying three different airplanes, and from making major
changes to improve the safety of the last Waco, a Mitchell B-10, a Dragonfly,
and now a Lancair 235/320 ... and many years as a Tech Counselor and Flight
Advisor, and I try to encourage other Experimenters to learn as much as they
can, I guess because I enjoy this wonderful past-time Paul Poberezny and his
WWII friends created for us, with the help of the FAA.
Terrence O'Neill
L235/320 N211AL
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