Investigation guidelines for mxers

Flying Safety, April, 2004 by Jeff Moening

An aircraft mishap has just happened and a safety investigation is started. What are you, the maintainer, to do? Too many times here at the HQ AF Safety Center we get reports where an engine or aircraft part was improperly tagged or identified, or maintenance started tearing into the part before an investigation was started. Sometimes the true cause was not determined or several possibilities were left that couldn't be ruled out. Here are some tips that will help you, the maintainer, during the course of a safety investigation, and will help the Air Force find the true cause of a mishap. The goal is mishap prevention.

First, STOP and talk to the person in charge of the investigation before you touch anything. Maintainers are get-it-done types, and when an aircraft is broken they want to fix it. In addition, there is the push to get the aircraft back to mission capable status as fast as possible. We understand that, but if an investigation into a mishap is to be done, you must stop and leave things alone until a plan is set up as to what is to be inspected and torn down, before you proceed. You want to get the big picture and look at everything before you tear it apart.

Now that you have your plan of action and the safety/investigation team is in place, you can start the process. Pick a spot to start from and work your way through the engine or aircraft part, documenting what you are doing along the way. It doesn't really matter where your starting point is, as long as it is documented and you stick with it.

Mark your parts as you remove them. Make sure the tagging is correct and you log what is taken away. Make your numbers and letters legible. Make sure other people can determine if it is a 9 or a 6 and your S and 5 don't look alike. In addition, make sure the writing utensil that you use will actually mark on the part and will remain legible. The key to all this is consistency. Once you start marking things one way stay the course and don't change the horse in midstream. Otherwise you will just confuse the people who will be looking at your work.

The old saying that a picture is worth a thousand words is still true today. Digital cameras are everywhere, and if your unit has one, use it. If not, make sure you talk to your wing safety office as they will have one, or be able to get the base photo lab to assist. Take a multitude of shots that cover the process from the start, before you start the tear-down, the disassembly process and the finished product with everything torn apart. Many things can be learned from the photos that you may have missed as you took the aircraft/engine apart. The engineers and other analysts that will look at your pictures may pick up something that you missed, but is critical to the mishap sequence.

It's time again to talk about documentation. Make sure when you took all those pictures you wrote down what they were of and why you took them. This way you aren't relying on memory, but on documented fact. If you are really on top of the game, make little signs or ID numbers that you put into the picture that reference your notes. This way there is no doubt about what the picture is of and why you took it.

Go slowly! This is one time where time is not of the essence. Take the time to do the inspection correctly, as the faster you go you may destroy evidence of the failure. Pay attention to each part and ensure everyone involved understands why you are taking it apart. Look for differences in the parts as you take them off. If you are trying to set the record for the fastest investigation, you will miss the subtle differences that may tell the story.

Observe everything and sweat the small stuff. This goes along with taking your time. Look at all the hardware and the little things that you would not normally look at. These little things can be the cause of the catastrophe. A key to look for is missing pieces. The little missing piece may be the starting agent for an engine FOD, or the cause of an electrical short. Besides, if the part has pieces missing, maybe there is a problem with the supply line that has gone unnoticed. Solving this could prevent the future loss of an airframe or aircrew.

Once you are all done, the safety gurus will pat you on the back for a job well done. Most importantly, the Air Force will have an effective record of what happened during the mishap. The goal of every safety investigation, or your own investigation, is to prevent future mishaps. Facts are what get the bad things changed in our Air Force. If you can present the bean counters with facts that the product is bad, or they need to redesign the process, or a supplier is not meeting standards, then they can act fairly fast and the money can come your way to fix the problem. Stating "I think it's bad" is not a good way to get the people who wear the stars, and direct where the money goes, to follow your suggestions.

I hope I have given you some guidelines to ensure your safety investigation is on track. If ever in doubt, contact your wing safety office. They are the local experts, and they can help ensure the right thing is done for the Air Force.