On Saturday, starting from Oshkosh, Dick Keyt will take aim at a closed-course record, piloting his wife, Debbie's, Polen Special, the 1972 creation of none other than Dennis Polen.

There is only one, and there will never be another. The Polen Special, Reserve Grand Champion at Oshkosh 1976, was finally sold to the Keyts in 1998, after a stroke left Dennis unable to fly it any more.

Polen built the plane in the late 1960s, using a lot of military surplus parts. While high-quality, they're now 50 years old. "Replacements are hard to get, sometimes," said Dick, the day before his record attempt.

There are a lot of nifty touches in this no-compromise racer, billed as "The World's Fastest 4-Cylinder Airplane," and which is thus the world's fastest 4-cylinder vehicle.

One which drew my interest is the little-bitty retractable tailwheel. "It's held up there with residual hydraulic pressure," Dick explained. "There's a spring always working to pull it down, and, after several hours, the doors open, and out comes the wheel." I wondered if he heard a disconcerting 'thunk' the first time it happened. "No; but I do feel a little draft on the back of my neck." However, Dick assured me, "It doesn't change the speed -- not one mph."

There are a lot of instruments on the panel, most of them old-style. Looking forward from there, you see something that's not too common in tiny airplanes: a static manifold. "There are so many instruments that require static," Dick said, "the manifold was the only way."

The engine, recently rebuilt by Mattituck, is a parallel-valve Lycoming 180 horse four-cylinder. There is no 'model number,' per se. "It's got a counterweighted crank, fuel injection, a turbocharger and intercooler. Without the turbo, Mattituck dyno'd it at 184 horsepower," said the man who flies it.

That turbocharger isn't just for normalizing, either. "We've run 39 inches at 21,000 feet," Dick said. For the record attempt, "We'll probably run a little less -- maybe 36 -- it depends on the altitude" where the record attempt will be made.

The record for this distance (495 km) is 1:00:05 -- 305 mph. To wrest the record, Dick will have to beat it by 1% -- 308+, therefore, is his goal. The flight will start at the OSH NDB, and Dick will then fly to Dubuque (IA) and back (with 3 GPS systems, plus the contest machinery, he'll know where he is -- probably to the inch). On his last record, he was often seeing speeds of 306 and better; he thinks he can do it.

The machine, as one might guess from looking at it, isn't a 'flying armchair' -- it requires constant pilot attention. Dick concedes, "The autopilot makes it pretty good for cross-country; it's hard, in IMC, to not bust altitude without it."

Dick's plan for the record is to leave the ramp about noon, take off at about 12:30PM, and climb to altitude for about 30 minutes, checking winds, before nailing the throttle and heading for Iowa. The attempt will probably be made between 20,000 and 23,000 feet, where the Polen Special is happiest -- and fastest.

[Note: The attempt on Saturday was close: Dick was just a minute and a half shy. He said the engine seemed a little off, and was having a few things checked, to see if he wanted to make another shot at the record...]

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