10 MARCH 2021 WorldWide Drilling Resource® Leading Indicators should be Followed by Britt Storkson Owner, P2FlowLLC According to Forbes magazine, the concept of leading indicators is sort of a “crystal ball” and are metrics which could help predict the future. They are kind of an extrapolation of existing patterns that, while not absolutely certain, give us a “window” into what will happen in the future. For example, if an employee has been incompetent in the past, he or she will almost certainly be incompetent in the future. There are exceptions, of course, but past practices can predict future performance to a great degree. These “leading indicators” can also indicate the probability of accidents. Certain negative actions or practices can greatly increase the probability of an accident happening. The story of AirAsia Flight 8501 provides many examples of flight crew practices that would suggest a high probability of an “accident waiting to happen”. AirAsia Flight 8501 took off from Surabaya, Java, Indonesia, for a flight to Singapore on Sunday, December 28, 2014. About an hour after take-off the Airbus A320 aircraft crashed into the Java Sea, killing all 162 people onboard. A Wikipedia report said the crash started with a malfunction in two of the plane’s rudder travel limiter units (RTLU). A soldered electrical connection that was cracked likely caused a caution light in the cockpit to intermittently turn on. The plane’s maintenance records showed the RTLU warning had been sent 23 times over the previous year, but was always solved (and never further investigated, which could have identified the underlying electrical problem) by resetting the RTLU system. When they say “resetting” the RTLU system they mean a “power on reset”. This means shutting off the power to the entire system for a time and then turning the power back on. While most in the industry downplay the need to “power on reset” a computer system, in reality it indicates a serious problem. Properly written and tested software should never require a power on reset to work correctly. In this case, the pilot did just that in an attempt to solve the problem. He shut off the circuit breaker powering the system because he had seen engineers in the past do it to correct this issue. The problem was, the particular circuit breaker he shut off was prohibited to be shut off in-flight, and he unknowingly shut off the power to other critical systems leading to the issues that caused the crash. I cannot emphasize this enough: Properly written and tested software should never require a power on reset to work correctly. Most of us drive our computer-controlled cars and use other computer-controlled equipment for years and never need to reset anything. I submit that any computer-controlled device that ever requires a power on reset should be immediately shut down and tagged out of service. Had this policy been implemented, it would have spared these 162 lives and probably many others. Britt Britt Storkson may be contacted via e-mail to michele@ worldwidedrillingresource.com Considering Attending? The Second Annual WorldWide DownHome DrillFest™ in Branson, Missouri August 16-18, 2021 The Chateau on the Lake Spa Resort and Convention Center www.chateauonthelake.com/ Take A Look!