U.S. Grounds 104 Hornets After More Cracks Discovered

[Rockville]

U.S. Naval Air Systems Command grounded 104 U.S. Navy and Marine Corps F/A-18 Hornet fighter jets March 12 after inspectors discovered the airframes were developing cracks much earlier than engineers had thought.

The grounding order affects the first four varieties of Hornet - models A through D - and does not apply to aircraft now flying combat missions over Iraq or Afghanistan. The number of Hornets affected makes up 16 percent of the Navy-Marine A through D fleet.

There have been no crashes or other mishaps related to the problem, said Navy spokesman Lt. Nate Christensen. The March 10 crash of a Marine F/A-18D Hornet from Marine Fighter Attack Squadron 224 off South Carolina - in which both the pilot and weapons officer were rescued - was not related to this problem, he said.

Of the 104 grounded jets, 77 are in flight status. Of those, 23 are in Navy and Marine Corps fleet squadrons; five are forward-deployed at Marine Corps Air Station Iwakuni, Japan; five belong to the Blue Angels flight demonstration team; and 44 are in fleet replacement squadrons. The other 27 Hornets are in a maintenance status.

The grounding notice from NavAir covered a "high stress focus area" that engineers already knew about as part of the Hornets' service-life assessment program, Christensen said, so NavAir issued a set of instructions for affected aircraft.

Squadrons have been ordered to perform a magnetic field inspection on jets included in the grounding. If they don't find cracks, their Hornets go back to unrestricted flight status, although crews are required to visually inspect the wings after every 100 hours of flight.

If a squadron can't do the magnetic inspection on a jet included in the grounding, its crews have been ordered to inspect its wings visually. Even if they find no cracks, the Hornet pilots will not be allowed to pull more than four Gs during flight.

Christensen said he did not have a breakdown for each type of Hornet - A, B, C and D - affected by the grounding. He also did not describe where the cracks were forming on each jet - for example, in their center barrels, wings, or elsewhere.

There are a total of 635 A- through D-model jets in the Navy and Marine Corps fleet.

Defense News, Published: 12 Mar 2010 15:12