Mike Goulian • September 05, 2014
You think your car is loaded with high-performance tech? It’s got nothing on the Edge 540 airplane flown by pilot Michael Goulian in the Red Bull Air Race series.
We interviewed Goulian to learn more about the technology behind his purpose-built race plane, how it handles up to 10G loads, and even found out a little bit about how his plane’s seat takes the words "customized interior" to a whole new level.
About the Edge 540
Goulian said the Edge 540 was originally conceived by Zivko Aeronautics as an aerobatics stunt plane, but had several attributes that made it ideal for the high-performance, high-speed world of Red Bull Air Race.
"We started out using Sukhois and Extra 300s and CAP 232s and Edge 540s, and it just turned out that the Edge 540, it was the lightest-weight airplane of all of them, and it had the ability to lose even more weight, so that was one of its benefits," Goulian said.
"The other benefit that it had was that the wing was really very well-suited for the Red Bull Air Race," he added. "In aerobatic flying, you pull G on a wing to a certain point, and then the wing stalls. And you want it to do that, because you want the airplane to tumble and do great snaprolls. So much of aerobatic flying is when the wing is stalled... so you want the wing to stall. In a CAP or Sukhoi, the wing stalls right at the perfect point, but on an Edge 540, the wing hangs on a lot more. That was one of its detriments as an aerobatic airplane was that it didn’t really like to snaproll that well, and it was known as an airplane that you kind of cheated on snaprolls.
"But that made it perfectly suited for the Red Bull Air Race, because in Red Bull Air Race, we’re trying to pull very tight circles and very aggressive hard turns in a very small radius, sometimes with not tons of speed. So that’s why the Edge has sort of turned out to be the machine of choice," he said.
From that race-friendly base, Goulian said the plane was given the same kind of treatment you might give a race car with the goal of maximizing acceleration, aerodynamics, and speed. Raised-head screws were exchanged for flush-mount screws. Fiberglass panels became carbon fiber. Select aluminum and steel components became titanium. Where possible, body parts have been shaved and lightened in the name of both weight savings and aerodynamic efficiency - for example, Goulian said the wheel skirts and landing gear struts were streamlined from their stock configuration.
The Edge 540 is a popular plane in Red Bull Air Race. That said, one way pilots seek to gain some performance upper-hand is by putting different tips on the wings that will give each plane a little bit different performance profile, Goulian said.
"That essentially gives more wing area and more aggressive pulling profile, if you will - the ability to pull more G at slower speed. If you look Nigel Lamb’s plane versus my plane versus Paul Bonhomme’s plane, they’re all a little bit different. Very personalized to the pilot," he said.
Another way the airplanes are different is in the cowling, Goulian said. With massive, 541.5-cubic inch Lycoming IO-540 horizontally opposed six-cylinder engines that rely on airflow for cooling, it’s important to find a good balance between aerodynamic efficiency and cooling efficiency - the two being diametrically opposed to one another.
"The engines, as you know, are air-cooled, so it’s all how you bring the air into the front of the airplane and out through the bottom of the cowling for efficiency, so everybody has worked a lot on that," he said. "They’re sort of like the wingtips. They’re very personalized."
We talk a lot about in-car electronics here, and airplanes have some hugely advanced electronics for navigation and communication purposes. At least, normal planes do. In the case of the Edge 540 Goulian pilots in Red Bull Air Race, however, electronics are minimized.
"The electrical systems in the airplane, they’re reliable, but they’re not robust. So they’re just enough to get the airplane started and to run the minimal electronics that we have in them. It’s just like a race car versus a street car," he said.
If I told you the Edge 540 race airplane had something in common with your smartphone and the Tesla Model S, you’d likely raise an eyebrow or two - but it does. Goulian said most race teams have moved away from gel cell batteries (think of those Optima "six-pack" shaped batteries you see in the auto parts store) to lithium ion batteries.
"It has been working fantastic. They’re really great," he said.
Workin’ in the mineâ€¦the data mine
Goulian said just like any car racing team, his Red Bull Air Race team mines data extensively by way of high-tech telematics gear.
"We’re now in the Air Race doing a lot of work with data-logging just like you’d see in a race car. Telemetry of the engine, telemetry of the airplane’s path through the sky, and all that good stuff. So there is a definitely a lot going on in making a race plane versus making a normal, run-of-the-mill aerobatic airplane," he said.
It’s interesting to me how plotting an airplane’s path through the sky takes into account a variable that telemetry of a race car’s path around a track does not: altitude. A race car’s altitude through a given section of race track would never vary more than a few feet, but an airplane’s altitude through a section of its race course could vary a lot.
In addition to the race teams’ data-mining work for their own edification, all race planes reportedly are equipped with TL Elektronic TL-3424_EXT accelerometers that keep fans informed of timing and speed stats that are displayed on large screens at Red Bull Air Race events.
Have a seat, get in the groove
When you pull up to 10G in an aircraft moving in excess of 200 MPH at an altitude much closer to the ground than most of us would be comfortable flying, you want to make sure your seat is bolstered very well.
To accomplish that goal, Goulian said his team worked with some of the same folks who design custom-molded seats for IndyCar racers.
"It’s funny, you know, one of the things that we are dealing with all of the time in aerobatics are the G forces. In the air race, we’re pulling upwards of 10Gs all the time, and it’s a pretty hostile environment, and you get thrown around a lot, and because we’re flying at low altitude, it’s also bumpy," he said.
"It’s one of the things that airplane designers just don’t pay attention to, and that is the seat. It’s really weird, but it’s almost just an afterthought.
"We are friends with a bunch of race car people, so we know what the IndyCar guys are doing. That seat that we made is made by the same people that do all the IndyCar parts for Penske and Ganassi and all of those guys. So if you’re sitting in this airplane, you don’t have to worry about trying to be comfortable, stay comfortable, or more importantly, staying centered in the seat, because you’re plugged right into it. It’s been a huge advantage for me to have that. It’s been great," he said.
Red Bull Air Race will have its next event in the Dallas-Fort Worth, TX area at Texas Motor Speedway on Saturday and Sunday, Sept. 6 and 7.
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