LEXINGTON PARK -- In about two hours, Siegfried "Ziggy" Hohenrainer fashioned the strips of mahogany to the precise calibrations his mystery caller had ordered without revealing their purpose.
Weeks later, a photo arrived in the mail with a stunning explanation. His $80 batch of wood strips was now glued to the wings of a sleek, gray, $44 million aircraft -- the FA-18E/F or Super Hornet, the Navy's newest strike fighter. The 3-foot-long triangular strips keep the wings from vibrating at supersonic speeds.
"I never thought they would glue them on an airplane's wing," said Hohenrainer, 65, a self-described "old world craftsman" who owns a molding and millwork shop in Waldorf. "It was shocking."
But not so surprising in the world of flight testing at Patuxent River Naval Air Station, where sophisticated computer-assisted engineering is occasionally augmented by good old-fashioned jury-rigging.
"Sometimes, you have to make temporary fixes so the airplane will go as fast as we need it to go," said C. D. "Pete" Pilcher, director of the Super Hornet flight test for McDonnell Douglas Aerospace. "It can save us a lot of money and time."
For a year, a team of 400 engineers, technicians, mechanics, pilots, photographers, some civilians and some Navy personnel, have been putting the Super Hornet through its paces at the base in St. Mary's County.
Their three-year mission is, in essence, to correct any deficiencies in the plane's design or construction before 1,000 are built for the Navy beginning in 1999.
At stake is the safety of Navy fliers and the defense of the United States, not to mention more than $80 billion of taxpayer money that makes the Super Hornet one of the most expensive aviation programs in the nation's history.
"This is the future of Navy aviation," said Capt. Joe Dyer, the Navy's FA-18 program manager. "It will be the primary aircraft for carrier aviation well into the next century."
The Super Hornet is an enlarged version of the FA-18C/D, the fighter-bomber that has been on aircraft carriers since the 1980s. The older plane has proved to be reliable and adept at delivering bombs and engaging enemy aircraft, but the newer version will have a far greater range, more powerful engines, a larger payload and a bigger array of weaponry.
But all those capabilities are meaningless if the Super Hornet ends up in the shop because some tiny part wears out or can't survive the rigors of combat situations. That's where the crews at Patuxent River come in.
Working out of the Hazelrigg Flight Test Facility, a large, spotless hangar named after an A-6 test pilot who died in a Patuxent River accident, workers pore over the plane and its parts, down to the washers. Jets are literally taken apart, their pieces individually analyzed for signs of stress or wear.
One jet is regularly dropped from a height of up to 25 feet to simulate a crash. (It never flies, nor does the model that just gets squeezed and twisted by machinery).
More typical is the aircraft that might spend a day getting launched over the Chesapeake Bay by a catapult identical to those on aircraft carriers.
"This is the best duty I've ever had," said Chief Petty Officer Ellis C. Rush, 38, an aviation mechanic who works on the Super Hornet's General Electric-manufactured engines.
"I've been the guy in the fleet who runs into a problem and wondered who the guy was who designed something. Now, I get to do something about it."
There are seven test planes capable of flight, the last of which was delivered to Patuxent River by McDonnell Douglas last weekend. Each has a specific testing purpose. One, for instance, is checked for high-speed performance, another strictly for how it handles weapons.
Sitting in the hangar, they all look sleek and powerful. But on closer inspection, small modifications that correct problems uncovered by testing are visible. The wood strips on the wings are a good example.
The wing vibrations eliminated by the strips were a relatively minor problem, but some corrections avert disaster. In November, for example, a Super Hornet engine overheated and stalled in flight. It took specialists three weeks to find the culprit, a redesigned compressor part that had failed. GE went back to its old component.
"It caused us a lot of grief," said Pilcher. "Twenty engines had to be taken apart."
Test flights are the focus of much attention. Each plane averages 11 such flights a month. Sensors attached to the plane transmit a flood of data to ground crews.
On Jan. 18, the Super Hornet passed a milestone when one of the test planes landed on the carrier USS John C. Stennis in its first sea trial. A large delegation of Patuxent River workers cheered from the deck.
"It felt quite comfortable," said Lt. Frank "Spanky" Morley, who piloted the plane through 50-mph winds. "It had a stable, smooth ride."