Piper Aircraft is patenting a new metal-bonding technique that will be key to the manufacture of the all-aluminum, $2.2 million PiperJet. According to Piper president and CEO James Bass, the intent is to eliminate the use of rivets altogether in the production wing and limit the number of rivets used in the main structure for the single-engine jet. Piper is also patenting a nondestructive testing system for its bonded structures.
Bass, who comes from a mechanical engineering background, told AIN last month that the bonding technique will allow for “lower labor costs and higher quality,” not to mention an aerodynamically clean natural-laminar-flow wing. He believes that “bonding technology has advanced” to the point that it is technically and economically feasible to incorporate into Piper’s largest airplane.
According to Bass, “The FAA is involved in every step of the metal bonding process” and is on board so far with the new technology. If successful on the PiperJet, the bonding technology will be applied to Piper’s other aircraft production lines, though this technology transfer is still likely several years away.
Piper manager of new product delivery Mark Miller, who is leading the bonding effort, said the parts count on the PiperJet’s wing will be quite low. The design calls for single-piece upper and lower skins, and the internal structure components (including the main spars) are each milled from blocks of aluminum.
At press time, Piper was manufacturing the first set of metal-bonded wings for the proof-of-concept PiperJet prototype in Building 12 at its Vero Beach, Fla. headquarters. However, the prototype’s upper and lower skins had to be made in two pieces and spliced together using rivets because of infrastructure constraints. That limitation will be eliminated when Piper constructs a new manufacturing facility for the jet.
Meanwhile, the main structure of the prototype was quickly coming together at Piper last month. This entire structure is being riveted together, since Piper is using the prototype’s wing as the real-world test for the new metal-bonding technique. Production structures will have a mix of riveted and bonded components.
The PiperJet wing is scheduled to be mated to the main structure this month, and Piper plans to announce subsystem suppliers soon. So far, the only known suppliers are Williams, which will provide the FJ33-4 engine, and Garmin, with the G1000 running things in the PiperJet’s front office.
First flight of the PiperJet is slated for the middle of this year, with deliveries expected to begin in late 2010 or early 2011. Piper said it has firm orders for 198 of the single-engine jets.