March 2001 111
a ToTal Fai Lure, Part 2: In the last episode, I gave some background
on Fédération Aéronatique Internationale (FAI) Pylon, or F3D.
To recap, F3D is flown primarily in Europe and the British
Empire. The aircraft are slightly larger and heavier than what we’re
used to in the States, but they are aerodynamically cleaner and go
almost as fast as anything, using full-piped .40s and “cough syrup”
fuel (80% alcohol, 20% castor oil, 0% nitromethane).
The Pylon section of the FAI rule book is only approximately
five pages. Most of the rules are one sentence long. There’s a limit
on engine displacement and there are minimum figures for overall
weight, wing and tail area, wing thickness, and fuselage crosssection,
but that’s basically it. The rest is up to you.
Engine modification? It’s unlimited; make your own from bar
stock, if you like.
Choice of propeller? It’s unlimited; mold your own from carbon
fiber, if you like.
Wingspan? It’s unlimited; give the model a 12-foot span and
three-inch chord, if you like.
The airplanes don’t have to look like a specific “big” airplane,
and there’s no prohibition on wing fillets, engine cowls, retractable
landing gear, or anything else you can think of.
Basically, if you can afford it and it will get off the ground, you
can race it in F3D. And F3D is the only Pylon event in which it is
possible to be crowned World Champion.
All this should make F3D wildly popular—at least if the “don’t
bother us with rules” contingent of the racing fraternity is right.
Unfortunately, the opposite is true.
One contest is held in the US every two years, to pick a threemember
team for the biennial World Championships. The number of
entries range between 10 and 20.
However, I don’t want to sound overly negative. After all, F3D is
not like an amateur softball league; it’s more like the Olympics.
Casual participants need not apply, and F3D offers room for
tremendous creativity to those who take the trouble.
The Cliff Telford/Bob Violett Bob C.A.T. I mentioned last
month represents such a burst of creativity.
Included is a photo of the Bob C.A.T. with its owners, which
Cliff Telford graciously supplied from his personal archives. The
Duane Gall, 1267 S. Beeler Ct., Denver CO 80231; E-mail: [email protected]
RADIO CONTROL PYLON RACING
Cliff Telford (kneeling) and Bob Violett (standing) with the Bob
C.A.T. racer mentioned in this month and last month’s column.
Dauntless-style retracts on author’s Bob C.A.T. offer less drag
reduction than standard setup, but more reliability.
The business end of the author’s Bob C.A.T. with the cowl in
place. Tape closes the glow-plug hole after startup.
112 M ODEL AVIATION
photo was taken in 1974 at Lakehurst, New
Jersey after Cliff and his teammate Bob had
won the Sopwith Trophy for the third
consecutive time.
Cliff explains about the trophy:
“In 1971, before the first International
Pylon Race was held at Doylestown PA,
Sir Thomas Sopwith donated a large
sterling silver cup to the FAI, to be used as
the top award in international Pylon
Racing. Sir Thomas is famous as the
designer/manufacturer of the Sopwith
Camel (WW I fighter aircraft).
“The Cup is passed on to each successive
winner of the FAI Pylon world championship
race. It remains the property of the FAI. Sir
Thomas sent a handwritten note to me as
follows [dated November 16, 1971]:
“‘Many thanks for the kind and
thoughtful letter from you and Mr. Violett.
I would like to offer both of you my
warmest congratulations on being the first
winners of the cup I recently gave for
Pylon Racing on an international scale.
“In 1914 we won the Schneider Trophy
at a speed of 89 mph. The last of the races
was won at over four times that speed. Will
the same thing happen with the models?’”
Look at the photo again. After you’ve
finished laughing at the ’70s clothes and
hairstyles, notice how minimal the model is.
Unlike a full-scale airplane, it does
not need to contain a pilot—only radio
gear. Therefore, the canopy is vestigial.
It’s there only to meet the fuselage
height requirement. Nobody’s head is
going to have to fit in it, so it’s just a
narrow bump.
Likewise, the “two-wheel” landing gear
(which you can’t see in this picture) has
wheels mounted in tandem, one behind the
other, in a streamlined pod on the bottom
of the fuselage. The rules did not specify
that the wheels had to be separated
laterally.
No doubt the rule-writers thought that
since full-scale racing airplanes have to
taxi and steer, and they do so using two
main wheels and a skid, the requirement
of “two-wheel” landing gear would be
sufficient to ensure the continued
scalelike character of the event, and
further detail would just clutter up the
rule book.
Guess what? Model racers don’t have
to taxi or steer; they get shoved into the air
by the caller. Bye-bye scale replicas, hello
center-mounted wheel pods.
To keep the wingtips from scraping, the
stabilizer is drooped slightly and fitted
with twin skids.
The innovations continue, but you get
the idea.
The Bob C.A.T. is a perfect example of
a notion that has slowly dawned on me
throughout the years: simple rules make
complex models. I could call that Gall’s
Racing Axiom #1.
And that axiom has a corollary—let’s
call this Corollary A: If the only rule is
“get to the finish line first,” the technology
will evolve so fast it will make your head
spin. In this regard, Sir Thomas Sopwith’s
question about quadrupling speed was
prophetic.
The first FAI Pylon race was held in
1971. By 1974—a scant four years later—
the Bob C.A.T. was state of the art.
Since then, a canopy-width
requirement and a wheel-track
requirement have been added. However,
the rules are still simple, and there are
still plenty of “opportunities for
innovation.” (A less-charitable term
would be “loopholes.”)
There’s nothing inherently wrong with
encouraging innovation, as long as you
know that’s what you’re trying to do.
The early Schneider Cup races were
partly intended to promote development
of new engines and airframe technologies
that could be used by the military. They
were successful; the Supermarine racers
of the 1920s led directly to the
development of the Supermarine Spitfire
fighter during the 1930s.
The “Spits” are widely credited with
blocking the Nazis’ attempt to invade
Britain in World War II.
Similarly, the “space race” of the
1960s (in which the only rule was “beat
the Soviets to the moon”) found and
exploited countless new materials and
processes, many of which are
commonplace today.
You might say the whole point of such
exercises was to create a massive incentive
for cheating, except that because there
were few, if any, rules to begin with,
cheating was technically impossible. All’s
fair in love and war!
New technologies are expensive. A
one-off prototype is much more costly
than the later production units based on
it. This is true because materials may be
hard to find (imagine Telford and Violett
trying to get carbon fiber for a wing spar
in 1974), and the development of
techniques to use those materials to the
best advantage is very labor-intensive.
Only the most stubborn individuals
are able to keep pushing ahead with one
failed experiment after another, until
they get it right. If they do, they go down
in history. If they do not, they go down
to defeat.
Therefore, it is no accident that
“simple” (read: unlimited) events tend to
be dominated by well-financed factory
teams or millionaires. Just think of the
last world land-speed record attempt, and
you’ll get the idea. In the case of the
“space race,” the only two competitors
were the two largest military/industrial
complexes in the world. How’s that for
an exclusive club?
This leads to Corollary B of Gall’s
Racing Axiom #1: If you want to keep a
lot of competitors in the game, decide what
existing technology you are going to
allow, and define it line by line and inch
by inch—even if it takes more words to do
so. Then prohibit everything else.
Quickie 500 was an attempt to do that,
and it almost worked—but I digress; this
column is about F3D.
To illustrate a principle I do not claim
credit for—circus-promoter P.T. Barnum’s
observation that “there’s a sucker born
every minute”—I will close with my latest
quixotic attempt at F3D.
This model was built for the biennial
US team-selection contest, hosted by the
Speedworld R/C Flyers of Phoenix,
Arizona the weekend of November 11-12,
2000. The top three finishers in the contest
constitute the team representing the US at
the World Championships this year in
Queensland, Australia.
I’ll try to have some pictures for you
next month. Meanwhile, this will have to do.
I realize I’m taking a big risk, going
public with this model before the fact; it
may fall flat. Even so, I’m looking forward
to seeing how it does and whether any of the
concepts embodied in it will be copied by
others in years to come.
The best result would be to do well and
to prompt a rules change, as the Bob
C.A.T. eventually did.
I’ve dubbed this effort the Loose
Ellipse. Its two main features are the
upright engine installation, for ease of
maintenance, and the backward-retracting
main wheels. There’s a small wheel in the
belly scoop, and a beefy nose skid to take
the brunt of the landing loads. That’s
right—it will land with the wheels up.
My reasoning is, wheels and wheel
struts are drag. If you could do without
them completely, that would be better.
However, the airplane does have to take
off and the rules require wheels of a certain
size, so they are a necessary evil.
The biggest problem with retracts is
making the wheels line up with the holes so
they will seal cleanly. Normal retracts close
inward. Each landing bends the struts, so the
wheels eventually stop lining up. Even if
they do line up, the wheels tend to pop out
of the holes in high-gravity pylon turns,
causing major drag.
Backward retraction gives less-thanperfect
drag reduction—the wheels do not
disappear. However, the strut lies fore and
aft on the bottom of the wing, rather than
crosswise to the airstream. The wheel does
not add significantly to the drag if it pops
out a little in the turn.
By landing with the gear up, I don’t
have to worry about tweaking the struts;
the alignment of the wheels and the holes
remains accurate.
If it works and it’s fast, I fully expect
someone to protest because I’m not putting
the wheels down to land—but the rules say
nothing about that.
So off I go into the land of innovation
(that is, loopholes) again. It’s a long shot,
and I’ll let you know how it works out.
I’ll have pictures of some more-normal
airplanes next month! MA
