Okay... Here's a(nother/ better) idea. Put a rotary on an airplane
(modified Supercub) and fly the poop out of it. Fly to OSH with it. At
the O-show, tear it down with everybody watching (and a video camera
running). Measure all of the parts and compare to new. Log the data.
Put it back together only replacing the necessary gaskets. Fly it
during the airshow. Tear it down a couple of times during the show,
reassemble and fly. Fly it home. Fly it 1000 hours during the year.
Do not make any mods to the airplane. Do not tinker with it. Come
back to OSH during the O-show and do the same exact thing again -
demonstrating lack of significant wear. People are concerned about
trouble free durability as well as loss of coolant.
Test to Failure (Terminal Effects Research) is certainly done on lots of
products, though I disagree with a few of your examples.. For instance,
a canopy that fails on the chicken gun fails acceptance. A de/anti
icing system that actually "fails" causes a plane to crash - failing
acceptance. Products are sold to meet a performance specification.
During qualification, once they meet the spec, testing can stop. Plus,
TER is not typically demonstrated in a marketing gig.
Testing an engine without coolant is fine. I think it's a potentially
low-bang-for-the-buck demonstration however. Doing it once or twice
would probably suffice. Maybe once per year at SnF would be good.
You'd definitely have to do some characterization work up front to
understand how hard you can run the engine (oil temperature might be a
way to monitor this) and still have it run. If it can make 150hp for
20minutes after coolant loss, great. Tell people that's what you want
to show. Or, better yet, come up with a way for it to run for a full
hour without coolant (is this possible with adequate oil cooling)? That
would be spectacular, even if you could only make 40% power during the
run. Or run it at idle without coolant for an hour, and then ramp up
the output to something like 50% and then run it for 20minutes (possible?).
I think there's room (a need) for a multitude of ways to demonstrate the
value of the rotary engine.
Here is a list of common gripes (rumors):
1. Fragile (see above)
2. Needs a PSRU
3. Needs coolant/oil cooling systems
4. Burns too much gas (poor BSFC)
5. Loud/Sounds Weird
6. Exhaust gas is ungodly hot - impossible to build a reliable exhaust
7. Burns lots of oil
8. Installations look too frankensteinish (complicated).
What else?
Each of these items must be addressed somehow. An item can either be
addressed by reliably demonstrating well thought out (engineered)
solutions, or by a marketing ploy, or (preferably) by both.
I think people would be impressed by somebody doing aerobatics demos in
a Skybolt (or similar) that's powered by a rotary of some kind. Ideally
they would go on a circuit where they made at least 6 appearances during
a season. It doesn't have to be unlimited style aerobatics, just
something with loops, rolls, and spins. Racing is great too, but I
think racing by itself implies a specially built, high strung engine
where lots of black magic has been done. Aerobatics implies inherent
robustness. Racing implies "motorhead." Lots of people want to fly and
not have to be a motorhead to do it. I think rotary engines say
"motorhead" thus far.
Regards,
Matt-
The Supercub idea looked like MOTS until you got to the "tear it down at
the show" part. I like that one. No, I LOVE that one. For that
matter, how about a contest, take a reciprosaur and a 13B apart (to the
MOH level), then see who gets their engine assembled first! We'll draw
the contestants' names, then provide an expert to coach them (let's
invite someone from Lycoming to coach, just to eliminate any possibility
of a rigged game).
One advantage of your idea is that the plane would be unremarkable --
that is, it wouldn't outshine the engine. In addition, it would show
the replacement possibilities.
However, I just checked my pockets and all of the cabinets here, and I
seem to have misplaced whatever Supercubs I may have had. ;) I have to
use what I can get.
Maybe next year I can provide an aircraft to do this with, but not this
year.
You seem to think that I intended to do the same demo every show. No, I
meant to do it just one time, then tear the engine apart and take the
pieces to other shows. Let people handle them, inspect them and compare
them to overheated reciprosaur parts.
Several of your points-to-address are typical of all auto conversions.
The one we need to shoot down is the reliability/fragility issue.
The first Chicken Gun was NOT built as a standards measure -- it was
built when (IIRC) Lockheed needed to prove that the (IIRC) P-38 could
take a birdstrike and still be an airplane afterward. There was the
belief that the propeller provided protection for single-engine
fighters, thus the Lightning was at risk. It was known as the "Sez YOU"
for years. Eventually, there was a standard developed to take advantage
of the testing capability.
Test-to-failure has OFTEN been used as a marketing tool. If you're old
enough, you emember the old Shell commercials, where they stuck
one-gallon glass bottles on two cars, filled one with Shell and the
other with another brand, and ran them until the cars stopped. They set
the baseline with the competitor's fuel, then the Shell car passed it by
and kept going.
The company that started making bulletproof glass marketed it by
shooting at it, first with a .22, then up one step at a time, in front
of a crowd at some big fair or World Expo or something, until something
finally went all the way through. Everyone knew the baseline, that
bullets go through ordinary glass.
45 years later, GE repeated the stunt with Lexan, using bulletproof
glass to set the baseline, and took a million-dollar order that afternoon.
We already have the baseline -- every other water-cooled engine out
there will seize within a minute of losing all the coolant.
Keith
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