Between the cracks

BARKSDALE AIR FORCE BASE, La., May 11, 2012 — From tip to tail, the B-52H Stratofortress is comprised of countless parts, each vitally important to enabling the massive bomber to carry out its mission. Each piece of this 185,000 pound puzzle must be routinely inspected to ensure the highest level of mission effectiveness and safety. This is where the Airmen from the 2nd Maintenance Squadron non-destructive inspection flight excel.

By utilizing one of several processes available, the NDI shop is able to determine if aircraft parts need to be repaired or replaced. Without these methods, maintainers would have to spend countless hours replacing costly parts.

"Testing the components is fairly easy and fairly quick, and it doesn't damage the part at all," said Senior Airman Paul Nessle, 2 MXS non-destructive inspector. "We can receive the part and have it inspected within 20 minutes."

With the rigorous operations tempo here, the mission can't afford to slow down long enough for each part to be disassembled and inspected.

One method of inspection is fluorescent magnetic particle inspection, a process that involves magnetizing a metal part before covering it with a fluorescent liquid.

If there are any cracks too small to see with the naked eye, the liquid will accumulate in them and stand out under a black light, explained Nessle as he stepped into a large blacked-out booth to perform the test. After dousing the metal rod in the special liquid, the inside of the pitch black booth glows bright green. The smooth, uniform color of the part indicates there are no cracks.

If the parts are structurally sound, they can be returned to the maintainers and placed back on the aircraft, Nessle said. This quick process saves on costly replacement parts, as well as the critical time it takes to wait for new components to arrive.

Other inspection methods are even more time efficient, allowing inspectors to determine damage while parts are still on the plane.

The numerous rivets that hold the aircraft together are common areas to find micro cracks, explained Nessle while calibrating an eddy current machine. The small black box sends a weak electric current through the part and registers any abnormalities on a screen.

These important checks are a regular part of every phase inspection that takes place on the B-52, said Senior Airman Jessica Cassiday, 2 MXS non-destructive inspector.

"We have our set inspections because there are certain problem areas of the plane where cracks are often found," she said. "Other than the routine inspections, we usually get calls from other shops who think they may have found damage, and we go out and verify."

No matter the method, NDI ensures every component of the aircraft that defend our nation is structurally sound and ready for the fight. This vital job is one among many maintenance specialties Airmen serve in to make the flying mission possible every day.