David Windmiller's 'Edge' Lives Up To Its Name

Dave Windmiller Has A Secret Weapon For World Aerobatic Championships

By Jan Churchill
Published: August 2000; Atlantic Flyer

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Dave Windmiller, 36, of Brooklyn. New York, is a member of the United States Unlimited Aerobatic Team competing for the World Aerobatic Championship in Muret, France from August 7 to 19, 2000. Going for the gold this summer will be intense competition with top pilots from 20 countries competing. Dave started flying when he was 14 and now has a commercial, instrument and helicopter license. He is very enthusiastic about flying the "EDGE 540" aircraft that is powered by a special TML (Teledyne, Mattituck, Lab) engine. To keep himself fit and proficient, Dave has been flying three times a day. Jay Wickham, vice-president of Teledyne-Mattituck, predicts great things from the combination of Dave, the extra strong "EDGE 540" and the special engine. "It's the combination of these three things," said Wickham. ''I'd like him to get an honorable mention in this tough. and political, competition his first time over there, to be noticed that he went."

Dave explained that the competition has changed so much in recent years that it was necessary to find an airplane that could meet the new parameters. "The lAC level of difficulty has increased over the past 10 years so that now a performance oriented aircraft is needed. The free program has a certain amount of difficulty with a maximum of 15 figures that can be used to accumulate points.

The level of competition is now so high that this level can be reached in six figures. The free program has required maneuvers with a set difficulty value. The least number of figures you can fly is six to get the difficulty score that you need. The new rule allows bonus points with 10 figures or less, up to the maximum bonus points. The contest rules provide bonus points for pilots who can reduce the number of maneuvers they fly from the maximum of 15 to a minimum of six. If a pilot flies fewer maneuvers then they must be more difficult. With bonus points they can actually wind up with a higher total score. "Given all the power that TML engine puts out, combined with the control response from the Edge. I've cut my program down to six maneuvers," said Dave. "My hope is to make a significant impression on the judges this year and then come back and win in 2001. No one else will have that kind of torque at their disposal and that seems to be what makes the difference at a WAC these days."

The EDGE 540

A performance aircraft is needed, one with a high roll rate, that is light and agile, and has a vertical penetration via a high thrust/weight ratio.

The Edge 540, built by Zivko Aeronautic in Guthrie. Oklahoma, will be flown by Dave in France. Dave said that, "Zivko is the master of composites, the best in the world." Zivko has designed an aircraft with tremendous power for its weight.

C. Todd Morse, project engineer who assisted in the design of the Edge 540 at Zivko Aeronautics, said that they have custom built 14 of these planes, each a little different. Of the nine aircraft flown by the United States team, five are Edge 540's (one is an alternate). The wing is stiffness driven and can sustain 10 Gs with less than two inch wing tip deflection. Todd Morse said, "The strength of the wing is enough to withstand 27 Gs." Maximum aerobatic weight is 1550 lbs. It has a climb rate of 3,700 feet per minute. The roll rate is 420 degrees per minute.

The fuselage is 4130 steel tube, powder coated, oiled inside. It is designed and fatigue analyzed on a computer. The lower aft fuselage is fabric covered to keep the fuselage weight at a minimum. The empennage is a unique airfoil, all composite with carbon spars and carbon skins. It has been static flight tested and had ground vibration analysis, and ball bearing hinges. Morse said. "The empennage is also stiffness driven so that its strength far exceeds what is actually required. The aircraft can withstand a lot more than the pilot. The ultimate load is +/- 15 Os." The wing is a unique airfoil, all composite with carbon spars. It has been static tested to 20 Gs, had ground vibration analysis, and been flight tested with over 2,500 hours of unlimited aerobatic flying. The fairings are carbon fiber, with large windows and panels for easy removal for inspection. The cowl is carbon fiber for low internal cooling drag. The canopy has a carbon fiber frame with a Hartwell latch and positive locking system with an emergency release. The control system has an aileron and elevator push pull system, while the rudder has a cable system. All systems are ball bearings with nylon bearings or ball bearing rod ends for ease of maintenance and smooth control response.

The instrument panel is carbon fiber with a basic instrument package and optional avionics. The fabric covering is Dacron with ZAI proprietary finish.

"It now flies like an Extra 230 with twice the power." said Dave. '''The vertical penetration goes way beyond any other piston powered aircraft in the world. Judges at WAC really like that. Where it used to be essential to plan freestyle programs that started at the top of the aerobatic box and finished at the bottom, it's now possible to start at the bottom and end up at the top. Energy management is a thing of the past. Now the key is keeping up with the airplane. The Edge 540 makes that easy.

The TML Engine

Windmiller is very impressed with the special project AEIO-555 engine that develops more than 340 hp at 2750 rpm. The hybrid engine was conceived and built up by the TML team of Lee Bandrw and Phil Haponic. Dave went to Mattituck for an engine because he used to know a mechanic there when he raced boats. Dave said, "The engine has performed beautifully and nothing has gone wrong. I have flown it about 100 hours. It has tremendous power for the weight. What amazes me is the strength of this engine. It experiences more abuse in a week than most engines would experience in 10 years, but it's always right there. Putting the airplane and engine together has been a labor of love with great results."

The engine was originally an IO-540C4B5, which when removed from an Aztec developed 250 hp. TML has improved to deliver the necessary power and torque for this demanding competition. Jay Wickham said, "We're trying to do something a little different and it's been intriguing. We've had a lot of fun with it." The engine is 95% Lycoming production parts with some modifications to the cam shaft and valve train. The valves come from Zanzi, an Italian company that makes Formula One racing valves as well as valves for the general aviation industry. It's an integration of automotive and aircraft ideas. Getting more air into and out of the engine has been a challenge. The increase in torque is about 20% to more than 630 lbs-ft, giving this engine a superb weight to torque ratio. It has fantastic vertical penetration and will deliver the power and torque ratios needed for top world aerobatic competition. The propeller is a Hartzell three blade composite HC-C3YR-IAX1.

The engine that powers Windmiller's Edge 540 is one of a kind. It has more than 100 hours on it and will be taken apart at Mattituck after the competition. It will be marketed after the competition, and within a year will get the new electronic FADEC system that Teledyne is developing.

The Pilot Dave

Windmiller has been flying three times a day in preparation for the world contest. Before leaving for France July 28 on a C5 out of Kelly AFB, Texas, Dave said, "No one thought any pilot or aircraft could withstand the G’s or have an aircraft with the roll rate demanded by this increasingly high level of competition which can last around 3 1/2 minutes, depending on the wind. The pilot needs stamina and the right aircraft. A performance aircraft is essential. You don't notice the G’s after you are fit.

"Dave commended the FAA for providing a practice box for him near his home base of Republic Airport on Long Island, New York. "They've been very cooperative."

Updates From France

Aerobatic enthusiasts can follow the progress of the United States Unlimited Aerobatic Team as it competes at the World Aerobatic Championship in Muret, France, by checking the team's web site during the practice week preceding the contest and then from August 7-9, 2000 at www.usafaerobatics.org. Steve Cunningham, U.S. Aerobatic Team executive director guarantees virtual front row seats for fans. The 2000 Unlimited Team is composed of nine pilots - five men and four women, plus a contingency of ground and support personnel. The ground support crew includes a volunteer team of manager/delegate, physician, mechanics, judge, assistant judge and recorder. "Committee individuals taking vacation or time from their businesses to ensure our nation is well represented on the world stage fill these essential positions," said Cunningham. Dedicated sponsors round out the support team. The sponsors are: Shell Aeroshell, Aircraft Spruce & Specialty, AMA, Champion, EAA, Fantasy of Flight Museum, Green Tree, Hartzell, Lycoming, Mattituck, Pilot Communications, Trade-A-Plane, Air Shows, lAC, Sun 'n Fun and Echelon Club USA.

The team members have devoted countless hours of intensive training to prepare for world competition. This will be Dave Windmiller's first time competing with this fantastically strong aircraft with its special modified engine. His aircraft has a high roll rate, is light and agile, and has marvelous vertical penetration. Windmiller is ready for performing the aerobatic maneuvers at the World Level that have transitioned over the past decade from a form of ballet to gymnastics. Today the European judges appreciate aggressive, high energy flying where energy is often considered more important than precision. Windmiller hopes to be able to demonstrate the capabilities of his unusual aircraft at a number of air shows this fall and next spring.