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Hi Matt,
I applaud your interest in
trying to understand your flying.
You might look at the December
1998 issue of Kitplanes magazine, page 96. There's a 6-page article i
wrote on Angle of Attack indicators. I flew P2V s in the Navy until 1957,
getting out the year after the US Navy first put AOAs on every carrier-based
aircaft, which cut landing accidents FIFTY-PERCENT -- 50% -- the first
year. Being in a Patrol Squadron we didn't have them, but when I bought the last Waco project I
restored it and began test flying it in 1963, and I found I needed to
know what the wing was doing in slow-flight. I had two years of
aero-engineering in college and learned in a wind-tunnel session one day that
wings can stall at ANY airspeed, but always at ONE angle of attack. So, as
there were no non-military AOAs on the market in the 60s, I made an AOA
indicator for myself.
I immediately learned that although I thought I 'knew' a lot about
flying, I didn't UNDERSTAND what controlled what.
I was surprised to immediately learn that I, the pilot, directly and
instantly controlled the wing's AOA with my elevator control. The
little free-floating vane on my AOA moved as though it was connected with a
string to the elevator. And that the wing's AOA could remain the same
in any flight attitude.
I found I could fly for an hour holding my Waco's wing just one degree
below the wing's stall AOA, while climbin it, zooming, making 90-degree banks,
etc., just by watching my AOA vane.
I learned that making steep approach turns in hot, gusty wind, to land ,was
'no sweat', since I could SEE exactly how close I was flying my wing to its
stall AOA.
I took-off once when the pitot
line pulled off the tube and I noticed zero airspeed on the A/S indicator, but
just glanced out at my AOA and relaxed... flew the AOA for climb around and
landed, and reconnected the A/S pitot tube.
I also noticed that I became
uncomfortable when flying in planes with no AOAs... which back then was
almost every GenAv plane.
Like a kid with a boom-box I
wanted to spread the joy, but quickly found that most pilots were comfortable
with what habits and instruction that'd expensively learned from the FAA-guided
courses and -- ho-hum -- said 'that's nice', and what else was new.
When I researched safety
records I found that about one-fourth of all GenAv fatal crashes resulted
from stall-spins, and nearly a third of all Experimentals. So I wrote
the '98 article for Kitplanes, eagerly accepted by Editor Dave Martin who was an
ex-Navy ROI in F4s and understood exactly how critical AOA info was for sale
slow-flight.
Going another step I contacted
the FAA's head then, Najeeb Hallaby, who lateralled me to his FAA Safety
bureaucrat, whose people wanted the indicator mounted on the instrument panel,
where a pilot should NOT be looking during a landing approach.
The FAA had a lot inertia in
their training curriculuum about airspeeds, and the AOA idea faded
away.
So I still felt philanthropic
and crusaderish and tried making and selling them. More education:
advertising is very expensive. One-off or short-run production makes parts
and labor costs high. But over the years I sold about 120 of them, the
majority to ultra-light guys who don't 'know it all', and some to ex-Navy jocks,
and guys flying for the few (then) airline companies that put AOAs on their
aluminum tubes.
Over the years I had to admit
that 'safety' was a hard-sell, and it was was disappointing and certainly
unprofitable, all that bother and work and selling them for less than $150.
I mentioned their availability
a time or two on this list but someone accused me of self-interest
with a hint of snake-oil-salesman-ness, so I just stopped making them
altogether.
But you can make a
completely adequate and functional one like mine, yourself. I still make
them for my own planes, the Waco tail-prop AristoCraft, my Model W, the Jake,
the Magnu V8 PickUp, my modified Mitchell B-10 'flying wing', our
Dragonfly, and have one on each wing-stub of our Lancair 235/320.
They are 'pilot information'
and can be put on any plane, with no FAA STC or PMA if you don't 'invade' the
plane's structure or systems. For experimentals you just do it
yourself. For TC'd planes just a mechanic's logbook entry. Some have
been clamped to Cessna or Aeronca wing struts. They could be glued to wing
skins. Only weigh a few ounces.
Before ANY instruments were put
an the newfangled 'airplanes', Orville and Wilbur put a floating piece of yarn
on their biplane, with marking to tell them at what angle they were flying their
wings. That was the first, and the essential, flight instrument. They
understood what they learned in their own DIY wind tunnel ... that wings stall
at an ANGLE!
You could DIY.
FWIW.
Terrence
L235/320 N211AL
at KGRE
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