Maintenance matters

Flying Safety, July, 2003

Editor's Note: The following accounts are from actual mishaps. They have been screened to prevent the release of privileged information.

Leftovers! Every month when I write this column I have too much material and the graphic artist has to cut some stories. Isn't it terrible that I never have a shortage of screw-ups? Well, here are some more cases where maintenance could have done things a little smarter.

Where Does The [O.sub.2] Come From?

An AC-130 Gunship Electronic Warfare Officer and Infrared Operator had some breathing problems a while back. The crew had problems during their pre-breathing and had to switch to the alternate regulators. They wrote up the primary regulators in the aircraft forms, and' maintenance did a complete checkout. Unfortunately, maintenance found no problems with the oxygen system. They also checked the crew equipment and found no problems. They signed off the aircraft forms and sent the aircraft back to flight. On the next sortie

Extra Parts?

A T-37 had just finished its mission and was heading to the parking spot when they had to declare a ground emergency for an engine fire light. Once the dust settled, maintenance found a flat washer lodged in between the terminals of terminal board number 30, which caused the fire warning light to short circuit. The washer was of the type used on the terminal board itself, but guess what was not missing any washers? If you said the terminal

Should I Write This Up?

A B-52 came back from a mission and was found to have a damaged trailing edge 30 percent by-pass duct. The duct to be replaced was the second duct installed in this aircraft while at this deployed location. Now we have a trend developing here, don't we? The previous history of this aircraft showed that three weeks after they installed the first duct the crew had the same problem. I guess the checkout wasn't as effective as they had hoped. This time, maintenance did a more detailed checkout and found that the [O.sub.2] line that feeds the two operators was kinked.

When the regulator had been installed, the maintenance person who attached the lines must have used some serious torque to kink the line. We in maintenance never invent a new way to do things wrong. We just keep relearning the same mistakes. Make sure you check the entire job before you sign things off.

board, you are correct. Now, this terminal board is not easily accessed, as you have to remove the left cockpit interior upholstery panel behind the left seat to access the terminal board. The lesson learned here? Where did the extra hardware come from? We must account for every bit and piece of hardware we use, and never leave anything behind. The extra hardware may do nothing for a long time, but it will eventually come back to make more work for all of US.

they found broken aft support strut assembly hardware for the duct while performing other work on the aircraft. The workers removed the broken parts, but they only documented the removal in the turnover log and never entered the removal in the aircraft 781 series forms. Now, is that the proper place to document a removed part? The aircraft then went for a contingency phase inspection, but the broken part was not replaced. It wasn't part of the phase inspection work package to look at this area. The aircraft had flown only 81.8 hours and six sorties since the previous duct was changed. Did the Air Force get its money's worth out of the $24,000 by-pass duct? Is it standard practice to not document removal of aircraft p arts? I don't think it is. Document everything you do. The few seconds! minutes you take to write it up may save you a lot more work in the long run.

QD Disconnected At The Wrong Time

A student pilot was completing a T-38 sortie when the crew had to return home via single engine because the right engine RPM wouldn't follow throttle movement. After an uneventful landing, the jet was turned over to maintenance. Upon depaneling the aircraft, the cause of the problem was easily detected. The right throttle control telescopic push-pull assembly quick disconnect (QD) was disengaged. Easy to see why the engine did not respond correctly. As the team looked closer, they found the QD would not lock properly per T.O. 1T-38A-2-6. The QD was replaced and the jet was back in the air.

What caused the QD to become disconnected inflight? The aircraft had recently undergone extensive maintenance. The aircraft had undergone major fuel cell floor work, it was the "CANN" bird and both engines were time changed. A lot going on, and after the repairs it was prepared for flight. The aircraft passed its check flight and had accumulated 27.6 hours before the incident. The "Book" provided detailed instructions on how to install the QD, and there was a local IPI requirement to ensure the slide collar cover extended beyond the finger segments. The IPI stated, "use every method possible, wiggle, tap, pull, shake, and cycle throttle through the full range to ensure the collar is seated and throttle does not come apart."