Problem spurs invention in Alaska of shock absorber for small aircraft.

By Melissa Campbell, Alaska Journal of Commerce, Anchorage Knight Ridder/Tribune Business News

Aug. 29--For years Burl Rogers has been able to look at a problem on an airplane and quickly come up with a part to make it better, lighter and more efficient.

He's got several certificates from the Federal Aviation Administration to show for his innovation.

Then a complaint from a friend put Rogers, owner of Burl's Aircraft Rebuild near Chugiak, on a seven-year road to the conception and design of his "Bouncing Baby." His "baby" is a shock absorber for small aircraft designed to better absorb the impact of landings than the traditional hydrasorbs.

"A friend of ours at a New Year's Eve party was grousing about the fact that he needed new hydrasorbs," Rogers said. "He was in the process of rebuilding his plane and couldn't find any. The company that made them for his plane went out of business and there was nobody else to replace them.

"He went on saying that the things weren't any good anyway -- they leak, wear out," he said. "Then he said, 'I don't know why no one can figure out a better way.' I thought to myself, I can do that."

For about three years after that conversation, Rogers batted the idea around in his head, maybe sketching out a thing or two. But for the last four years, he said, "It's become nearly a daily obsession."

Rogers designed the system, officially named the Alpha Omega Suspension System, to be virtually maintenance free.

"There's nothing to leak out, no oils, no gases, no springs," he said.

"There's very little wear on anything."

The system has been fully approved by the FAA and the first systems should be available by the end of August for several Piper PA models.

The conventional hydrasorb system consists of an absorber wrapped with a thick bungee cord. It has two fittings that slip over either end. One end attaches to a V-shaped rod beneath the plane; the other is attached to a rod that hooks onto the landing gear. A vinyl cover, offering some protection against dirt, water and other elements, goes over the main component.

Hydrasorbs require vigilant maintenance, however. The bungee has to be replaced often, and the cover that protects the system can tear easily, depending on landing conditions.

But one of the more disconcerting aspects of the hydrasorbs is the bounce effect, Rogers said.

"It's very unforgiving," he said. "It's really a series of rubber bands wrapped around that. A hard landing will spread the landing gear out and then catapult the plane back into the air again."

After the landing, it's a continuously bumpy ride, sort of like a washboard effect, down the taxiway. All of that is hard on the plane's frame, not to mention the pilot's spine.

The Alpha Omega system smoothes out that seat-tingling trip down the taxiway and nearly eliminates the bone-jarring slingshot effect from a hard landing.

The system uses a solid polymer as a suspension and shock-absorbing medium.

The housing is steel plated with nickel, zinc and a clear conversion coating to offer protection from the elements. Fittings that connect the system to the plane are welded to one end, and the other is sealed with an epoxy mixture. The tubes that connect the system to the plane and landing gear are made of titanium.

They are adjustable, and the only maintenance is the occasional replacement of an $8 seal. The initial investment is $2,200 for the pair. The bungees on hydrasorbs have to be replaced fairly often -- annually for guides or every couple of years for recreational users -- at a cost of just under $100.

Replacing the shock unit costs about $560, and could last for several years.

One of Rogers' absorbers weighs in at about seven pounds, more than a pound lighter than the hydrasorbs.

"Only two things will destroy these: A direct hit and fire," Rogers said.

In testing, Rogers' system indicated that a plane would bounce only about a half- to three-quarters of an inch off the ground, compared with up to two inches using the hydrasorb system.

"This landed softer, with less impact on the frame of the plane," Rogers said. "It hit the ground and just sat there."

That test, using a drop method from a height of 18 inches, was the 212th test to perfect the system.

"We know 211 ways it doesn't work," he said. "We have configured this in every way you can imagine. Nobody had ever used these materials in this application, so there was no data to start with."

Sales will primarily be through the Internet, Burl's Aircraft Rebuild catalogues and by word of mouth.

Rogers discovered his knack for rebuilding planes in the late 1970s, when he worked at an aircraft maintenance shop in Lake Hood. He got his pilot's license in 1977 and promptly bought an Aeronca Sedan, a favorite aircraft of his father, to rebuild for himself.

He rebuilt five planes before he finished his own, in 1981. But he used his plane to develop several modifications and improvements that he still produces in his Birchwood shop today.

"It became apparent that as long as you followed the rules, you can make about anything your mind can possibly conceive," he said. "I loved rebuilding airplanes. I realized then that this is what I wanted to do."

In February 1982, Rogers opened his own shop, Burl's Aircraft Rebuild, and became a licensed airframe and power plant mechanic in 1982. He received an inspection authorization in 1985.

He's also a manufacturer of airplane parts, from small replacements for rebuilds to the Magnum I tail ski, which he designed for his own plane and began selling in 1982. The Magnum I has never had a failure in the 22 years since its inception.

"The prime objective in everything I've built or designed came from a maintenance standpoint," he said. "Most aircraft I've worked on were not well maintained. But I know I'll have to rebuild, tear them apart, so why not design them so they are as easy to tear apart as they are to use."

In 1999, Rogers purchased the certificate and approvals for the Mitchell 15AC Sedan, perhaps better known as the Aeronca Sedan. This gives him the exclusive right to manufacture the entire aircraft and all its parts, and he has ownership of all technical data for the plane.

Only about 586 Aeroncas were built, between the years 1948 to 1950.

"All the tooling was lost," Rogers said. "So everything we make, the first thing we have to do is make the tool to make the part. That doesn't double our work, it triples it."

Web resources: www.aoss.net.

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