Pilotage

Oshkosh walkaround

October 1, 1992

My last pilgrimage to the Experimental Aircraft Association Fly-in Convention was in 1969 (to Rockford, Illinois) made in a Curtiss C-46. It was a huge and wonderful rendezvous then. This year, I showed up at Oshkosh in a Hertz Topaz, and the event was still wonderful, but the scale now exceeded normal human experience. I had to discipline myself to avoid squandering in a few hours my entire allotment of oohs, aahs, and adrenaline, to be left standing, eyes glazed, in balding Reeboks.

The most impressive part of the convention could not be fully imagined. That was the effort, the thousands of man-hours of love-labor in each of 2,400 show airplanes (and 10,000 other birds of every stripe) and the labor of thousands of volunteers without whom the evidence could not be displayed.

My focus was drawn to the entrepreneurs who continue to fly in the face of dire reports and to display a spirit of free enterprise not often seen these days. They are reinventing an industry and taking risks that reveal not profit motive so much as a love for aviation.

Two exhibits in particular struck me as serious moves toward the twenty-first century:

German engineer Michael Zoche's aero-diesel engine is characterized by extreme cleverness of design. Seen at Oshkosh before (but yet to be heard running there), the engine was on static display. Nonetheless, according to Zoche, it has amassed 1,100 hours on the bench and received German, U.S., and Japanese patents, with others pending. Certification is in process with the German LBA (its equivalent to the FAA). Zoche seeks simultaneous certification for Normal and Acrobatic categories and helicopters under JAR-E and FAR Part 33.

It is a one- or two-row, four- or eight- cylinder radial diesel with a two-stroke cycle. The design is entirely different from many gasoline-fueled two-strokes, by having a full pressure oil system and fuel injectors. Scavenging is provided by a supercharger and a turbocharger, much like American Detroit Diesel two-strokes. Piston ports are used rather than a valve train, which dramatically reduces the parts count and holds the maximum engine diameter — including accessories — to 24.7 inches.

The unique radial layout has no master rod. Rather, the four interlinked rods have slippers that each bear on one fifth of a common single crank journal. With no separate intake stroke and constant boost, the pistons, pins, and bearings operate with only varying degrees of positive pressure, never banging back and forth through their clearances as happens in all other reciprocating engines. This layout is also theoretically 100 percent in balance statically and dynamically. Zoche says that it's the smoothest-running recip ever tested by the ZF Corporation, which makes the accessory drive gears. There are, by the way, three accessory drive pads to accommodate two vacuum pumps and a prop governor and also a crank-driven, brushless, 24-volt, 40-ampere alternator that has no bearing surfaces.

The engine itself has no electrical requirement. Starting is done by a 2-pound device that sends compressed air from a small tank through the gear-driven supercharger to turn first the oil pump — to achieve pressure — then the crank to fire up on the first revolution in typical diesel fashion.

The 163-cubic-inch four-banger makes 150 horsepower at 2,500 rpm (direct drive) on Jet A, JP-4, or diesel fuel. It weighs just 185 pounds complete. The 326-cu-in eight makes 300 hp, weighing just 259 pounds. Piston speed at full rpm is a low 1,540 feet per minute, favoring Zoche's claim of a 2,000-hour TBO.

An engine design this revolutionary can have many unforeseen pitfalls, and a raised eyebrow is a healthy eyebrow. Nonetheless, Zoche has so far made slow, deliberate, and proper moves and certainly bears watching.

Speedy kitplanes have had great appeal and some success for years but have been — up to now — hampered by two serious drawbacks, namely: They are tiny, and they are kits.

The average pilot with the bucks to spring for an aircraft is at least 45 years old. He wants to sit up, not lie back. He wants to choose his companions for their amiability, not their size, and no matter the thickness of his billfold, he can't afford to spend one fifth of his remaining life building an airplane just to get airborne.

Enter the Lancair ES — a big, roomy, full four-seater, sitting on tall, sturdy, fixed, spring-steel gear with normal-size tires. Its 35.5- foot wing has 140 square feet of area, large slotted flaps, an aspect ratio of 8, and carries 73 gallons of fuel. The latter feeds a six- cylinder, Teledyne Continental IO-360-ES of 210 hp. While ancestors of this engine have been somewhat maligned for having a short, cranky lifespan, this model — according to designer Lance Neibauer — offers the best fuel specifics in its power class and a 2,000-hour TBO.

Best of all, this "real" airplane has the same combination of qualities that guaranteed the success of the Cessna Skyhawk/Skylane series, with bigger portions all around. The cabin is about 6 inches wider and 5 inches higher than that in my 172. With an empty weight of 1,650 pounds and a gross of 2,850 pounds, the ES will carry full fuel plus 771 pounds of people, bags, and radios, more than 1,000 nautical miles with reserves at 165 knots. That's 1 statute mile per minute faster than my Skyhawk and more than three times the -ES's 50-knot stall speed. Neibauer says that his fuel burn on the way to Oshkosh was less than 10 gph. He also says that the ES will haul just about whatever you can slam the door on and cannot be loaded aft of CG without exceeding max gross by hundreds of pounds. And he will seek certification under new, simplified rules.

Okay now — both eyebrows are up, but I'm ready to charge into the new millennium. Say, Lance, I believe that's Michael on line one.