Accidental Classic

From the designers who brought you the P-51 Mustang, an airplane with a complicated past…and a controversial present.

So popular is the Navion that airplane lovers consider a complete restoration, like David Peters', the proverbial pot of gold at the end of the rainbow. (David Peters)
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In May 1960, Bob Swanzy, a retired road construction engineer from Greenwood, Mississippi, was driving through Memphis when he saw a 1947 Navion for sale. He bought it for $4,500, and some 5,000 hours and four engines later, he is still flying it. “It just suits me,” Swanzy says. “You can load it down with baggage. You just crank [the engine] up. If the tail comes off the ground, you go.”

Dick McSpadden, who flies out of Canon, Georgia, and is the former president of the 156-member Southern Navion Air Group, agrees. “Whatever you can put into it, it’s going to fly. At 75 miles per hour, it is going to come off the ground.”

Ron Judy, who is the American Navion Society’s chief technical advisor, says that in cross-country trips, the Navion really shines in “dirty,” or turbulent, air: “When I’m flying through moderate turbulence, I barely feel it. Meanwhile, a guy in a Cessna 150 in the same air is getting beat to death.” Judy, a Gate, Oklahoma rancher who spent six years restoring his Navion, says the structure and area of the airfoil contribute to the stability. “It’s a monocoque wing with no spars, just ribs, stringers, and subspars to hold the [retractable] landing gear. The wing skins and stringers provide the structural strength. The wing is evenly loaded across a large area. The wing design delivers a smooth ride and high lift and makes the airplane very controllable at low speeds.”

The Navion’s wing consists of two different airfoils that join approximately 50 inches from the wing root. With landing gear and flaps extended, a Navion stalls at just 48 mph, about the same stall speed as the much smaller—and much lighter—Cessna 152.

Ruggedness and stability aside, most owners were initially attracted by the aircraft’s distinctive good looks. “It’s coming from an era where design for aesthetic purposes was as important as anything else,” says David Peters (who provided artwork for this article).

In issuing the Airworthiness Directive, the FAA cited nine Navion accidents generally associated with the fuel system, three of which were directly linked to the fuel selector valve. The agency also speculated that many of the existing valves might be reaching the end of their serviceable lives.

Gardner claims that since his company bought the Navion type certificate, 18 fuel-system-related accidents have occurred, and that he issued a service bulletin recommending action to Navion owners as early as 2004. Most of the accidents occurred on takeoff at high engine power settings, when defective or improperly repaired valves allowed the vacuum fuel system to ingest air, causing the engines to stop.

Navion owners who objected to the AD succeeded in getting the FAA to slightly modify it. “The proposed AD, with the references it used for doing the inspection, left much to be desired, safety-wise,” said Judy. “The American Navion Society wrote a Service Bulletin and submitted it to the FAA, and the FAA included portions of it in the final version as a means of conducting the inspection.” Judy, who had a valve fail 17 years ago, now believes the AD is acceptable, but prefers the Alternate Means of Compliance (AMOC).

According to Gardner, he and the Navion Society are competing parts suppliers. He says that the paperwork-intensive and time-consuming AMOC—a detailed inspection that does not preclude the need for valve replacement and is available only to society members—is actually more expensive than simply replacing the valve in the first place. Judy points out that the stringent inspection of the fuel valve required under the AD virtually guarantees that the valve will not pass.

Even with the AD and accompanying controversy, McSpadden maintains that Navions are relatively inexpensive to maintain: “Our parts are less expensive than for almost any other airplane.” And whether following the AD or pursuing the AMOC, Navion owners are doing whatever it takes so that they can continue to fly their favorite aircraft.

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