News

Start Your Engines

  • Published
  • By Jenny Gordon
  • Robins Public Affairs
Even aircraft engines removed from powerful Air Force weapon systems need an oil change every now and then.

As part of our ongoing "Home Away from Home" series, which debuted last September, our in-depth coverage over the last four months has highlighted various stages of the programmed depot maintenance of a C-130H at the Warner Robins Air Logistics Complex. 

During Gate 4 when scheduled inspections occur, outboard engines on the aircraft were removed in early December and routed to the C-130 Engine Shop in Bldg. 44. 

After all, you can't do anything with an aircraft if nothing is there to power it up. That's where the engines come in. 

And to make sure they're safely and properly maintained, a crew of at least three people arrived from the engine shop to first remove any connections each engine has to the plane, including just four bolts. Once that's done, safety caps and plugs are installed, and a crane gently removes and lifts the precious cargo for transfer to its temporary home a few hangars away.

So what happens when a 5000-pound engine is hauled in? First, mechanics open up all the cowlings - the metal covering the entire engine, to take a closer look inside. Then, the oil is drained and oil filters are carefully checked for any contaminants that could indicate an engine is malfunctioning.

  That's one of many things the engine shop mechanics look for to ensure they have a good engine. 

Sometimes when bearings start to go bad, it will vibrate, which then causes metal shavings to get bigger and bigger until they're picked up in the oil, magnetic particle plugs or in the engine's filters. 

If no metal particles are detected in the oil magnetic plugs or engine filters, the fuel and hydraulic filters are removed and replaced. Then inspections begin. 

"We change the oil, all the filters; we lubricate it; we check for minor problems, and then we put it back together," said Stephen Welchel, 560th Aircraft Maintenance Squadron Engine Shop supervisor.

The engine, which takes 40 quarts of oil, is inspected from front to back as part of its 56-hour work package. They'll look for hoses that are out of date. Teflon, for example, can be used indefinitely; rubber hoses wear out and must be changed.

Clamps and bushings are checked; the entire engine is checked for signs of any cracks, and six fuel nozzles are removed, checked and reinstalled. Boroscopes are used to visually inspect all the engine's blades for any chips and cracks.

Just like in a car, an aircraft's engine contains an igniter, located at the back.

"It's nothing more than a spark plug,"  said Welchel. "It just takes one time to start things up, then it sits there until it's needed again."

Once you have ignition, the turbine turns providing the pilot with bleed air, hydraulic, AC and DC power, and the torque necessary for take-off and flight. 

Few if any pieces from the inside are completely removed from the engine. If major damage is found, it's a phone call to home station to see what the customer wants done. 

As part of that work, the engine's propellers, which take 22 quarts of hydraulic fluid, are also inspected. Its edges are checked for any chips, possibly as a result of rock damage.

On this day's inspections everything looked good, and there were no oil contaminants, according to Welchel.