Don’t let lessons learned become lessons lost Published Sept. 24, 2009 By Maj. Christopher Hague 22nd Maintenance Operations Squadron commander MCCONNELL AIR FORCE BASE, Kan. -- Throughout our careers, we've all learned lessons about doing a job better, avoiding injury and not damaging equipment. We read about it in inspector general and safety reports, professional magazines and so on. Like many, I would read them and get a little information out of them. And when it came to safety lessons learned from an unfortunate incident, I always thought that stuff only happened to "That Guy." On Feb 23, 2008, I and 93 of my fellow aircraft maintainers became "That Guy." It was the last day of a five-month deployment, and we were preparing a B-2 Spirit for a flight home. We encountered a maintenance problem we had seen a few times before. The air data system that determines airspeed and altitude required calibration. Our technician went into the aircraft, technical order in hand, and performed a calibration of the system. Diagnostics confirmed everything was good-to-go. The aircraft taxied along and headed to the runway. We gathered next to the runway to see them off and celebrate a successful deployment. One aircraft took off. Then, the B-2 started rolling down the runway. That's when our lives changed in an instant. The B-2 lifted off the ground, suddenly stalled, and crashed right in front of us. Fortunately, the pilots ejected and were safely recovered. But the B-2 came to rest a few hundred yards from us in flames. After several months, the accident report was released to the public. Initially, it sounded like a happy ending to something no maintainer or operator ever wants to experience. We did everything in accordance with the technical data. We made no mistakes in the performance of our duties, and there were no fatalities. However, there was a catch; lessons learned had become lessons lost. It turned out the problem we experienced with the air data system requiring calibration was the cause of the crash. Moisture trapped in the system was causing inaccurate readings in the cockpit and made our calibration inaccurate as well. An investigation confirmed the technician did everything correctly, but the T.O. was deficient. Sadly, this T.O. deficiency was identified a year earlier during a deployment to the same location. Technicians on the previous deployment started using a heating system to evaporate moisture prior to system calibration. This technique reduced the excessive amount of calibrations and worked like a champ the entire deployment. Unfortunately, this lesson learned became a lesson lost when that deployment ended. This technique was never documented or incorporated into the T.O. One year later, this lost knowledge was a contributing factor in the crash of a B-2 and nearly cost the lives of two pilots. What we perceive as a minor problem today might have unforeseen consequences tomorrow and cost time, money, equipment and even lives if we don't take action. When we see a problem, we have to solve it, document what we did and pass it on. Don't let lessons learned become lessons lost.