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Photo Information

Sgt. Rick Finlay, a Marine All-Weather Fighter Attack Squadron 225 maintainer, holds the flexible end of a borescope in position so another maintainer can see the internal blades of the F/A-18's engine during exercise Air Warrior here June 24. Although the maintainers work hard, there is only so much they can do and when an engine is too damaged there is no alternative but to get a replacement.

Photo by Cpl. Joseph Marianelli

Air Warrior off to rocky start

24 Jun 2009 | Cpl. Joseph Marianelli Marine Corps Air Station Iwakuni, Japan

After one day of flying in exercise Air Warrior, a multi-lateral exercise demonstrating joint and multinational capabilities and improving interoperability between the United States and Malaysia, Marine All-Weather Fighter Attack Squadron 225 lost the use of an F/A-18 due to engine damage here June 23.

To combat future potential engine damage, an all-hands foreign object debris walk took place June 24.

“For that to happen the first flight being here, it’s a big deal,” said Lance Cpl. Wesley Alexander, a Marine All-Weather Fighter Attack Squadron 225 maintainer.

When debris is sucked into the jet, it enters the low pressure compression section where fan blades are rotating at incredible velocities.

Think of it like dropping a penny off the empire state building.

Sure it’s just a penny, but as it travels through the air gaining momentum, the insignificant penny becomes a serious danger.

The same things happens when a small object is sucked into a jet engine, the object is ping-ponged around gaining momentum and scoring surfaces it comes into contact with, said Gunnery Sgt. Gary Walker, VMFA(AW)-225 maintenance control chief.

Ironically the power allowing the jet to operate is what makes FOD such a problem.

Even minor fan blade damage is taken seriously because the engine relies on extremely fast moving parts, said Walker.

Jet engines are composed of a series of tiered fan blades.

Sometimes very minor damage on the first tier can be corrected through filing techniques, said Alexander.

In this particular instance, the damage was done to what’s called the third-stage fan and the only option is to have an entire engine shipped from Marine Aviation Logistics Squadron 12 at Marine Corps Air Station Iwakuni, Japan.

Maintenance for jets is divided into an organizational level which is the VMFA(AW)-225 maintainers, and the intermediate level which is where serious maintenance jobs go, said Walker.

At the organizational level, the maintainers used a borescope, essentially a flexible tube with a camera on the end, to view the internal fan blades.

Once the damage was discovered there was little more to be done at their level.