Wreckage of the downed Hornet

April 13, 2012
Virginian-Pilot|by Kate Wiltrout

Loss of power, or loss of control?

That may be the biggest question facing the team investigating the cause of last Friday’s jet crash in Virginia Beach.

The Navy has said the F/A-18D Hornet that hit an apartment complex shortly after takeoff from Oceana Naval Air Station experienced a “catastrophic mechanical malfunction,” but a detailed explanation will likely take weeks or months.

Boiled down to the most basic terms, the Navy investigation will try to determine whether the doomed Hornet had a problem with its engines, which stopped generating thrust needed to keep the jet aloft, or experienced failures of its hydraulic system or electronic flight controls, either of which could have rendered the aircraft uncontrollable.
Beyond that basic distinction, things quickly get complicated. Various scenarios could lead to either outcome:
** A ruptured fuel line spews jet fuel into a hot engine bay, which catches fire.
** Birds are sucked into one or both engines.
** A “foreign object” — like a wrench accidentally left inside an engine during maintenance — causes a major malfunction.
** The flight control computers fail shortly after takeoff, forcing the plane into an unfamiliar mechanical backup mode that gives pilots far less control.
** Fan blades fly out of an engine that has catastrophically failed, cutting hydraulic and fuel lines.

The so-called “legacy” Hornet — the precursor to the upgraded Super Hornet, which also flies out of Oceana — is one of the Navy and Marine Corps’ longest-serving and most reliable planes. The D model, a two-seat version, entered the fleet in 1987. It’s more common in Marine Corps squadrons, which have 92 of the planes; the Navy flies 39 of them, according to Cmdr. Phil Rosi, a Navy spokesman. One of the Navy’s highest-profile squadrons — the Blue Angels flight demonstration team — flies the F/A-18D.

Those who’ve spent time in Hornets sing their praises and talk admiringly of the twin General Electric F404 engines that power them to supersonic speeds. Numerous Navy Hornet pilots — both retired and active duty — said they never experienced an engine malfunction during their careers.

“It’s an extraordinary airplane in terms of its resilience,” said George Dom, a retired Navy pilot who served as commander of Carrier Air Wing 7 at Oceana and, before that, as commanding officer of the Blue Angels.

Dom, who retired in 2003, said he lost a leading edge flap while flying a Hornet at very high speed and was able to land. And he said he’s seen Hornet pilots survive midair collisions and return to base.

One scenario experts and pilots discount in Friday’s crash is dual engine failure.

“The reason that Navy planes have two engines is because the odds of two engines failing simultaneously are close to nil,” said John Pike, a military aviation expert who runs the website globalsecurity.org. “It would have to be a common failure mode, and one thing the two engines have in common is the fuel system.”

Pike theorized that the jet, which belonged to Oceana’s training squadron, the Gladiators of Strike Fighter Squadron 106, had a clogged fuel line … READ MORE

Advertisements