Quiet Technology Aerospace has engineered a solution to a recently discovered corrosion issue on the Gulfstream IV’s engine inlet cowl attachment flange holes and the forward fastener line of the inlet's acoustic inner barrel.

For the former problem, the company has developed a proprietary repair procedure, which it claims is more economical than replacement and eliminates the return of any corrosion on the inlet cowl flange attachment holes. QTA said that the standard bushing repair does not always clean up corrosion around the hole edge. Thus, during the company's repair process, the flange is removed from the inlet, completely stripped and then Alodine-coated and primed to protect against further corrosion.

For the forward fastener line repair, QTA’s solution replaces the alloy steel fasteners with monel, which is a nickel alloy—composed of up to 67 percent nickel,copper, and with small amounts of iron, manganese, carbon and silicon—that has high corrosion resistance.

In addition, QTA said that its engineering and DER staff has “full capability” for composite repairs on all GII, GIII, GIV and GV parts. Its composite specialties on these Gulfstreams include flight controls, nacelles, winglets, fairings, doors and floorboards.