RADIO CONTROL PYLON RACING
Duane Gall, 1267 S. Beeler Ct., Denver CO 80231; E-mail: stinger4@earthlink.net
A Total FAI, Part 2
In the last episode, I gave some background on Fédération Aéronautique 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 cross-section, 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 three-member team for the biennial World Championships. The number of entries ranges 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 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.
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.
Gall's Racing Axiom #1
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 Spitfire is 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 Speedway 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 fail 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-than-perfect 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
Features of the Loose Ellipse:
- Upright engine installation for ease of maintenance
- Backward-retracting main wheels
- Small wheel in the belly scoop
- Beefy nose skid to absorb landing loads
- Designed to land with the wheels up
Transcribed from original scans by AI. Minor OCR errors may remain.
