Building error tolerance, error mitigation, and error-capturing strategies into our systems should be one of the most important outputs of safety management, especially when guided by a robust FAA safety management system and supported by formal safety risk assessment processes. These strategies are a hallmark of good system design. And when system design flaws are discovered, risk controls are implemented. Monitoring of the affected process then helps us see if our strategies are effective. If not, our previously-implemented controls must be corrected to keep a hazard in check. Way back in the 80’s I was serving as DO for Salair Air Cargo, operating a fleet of 10 old DC-3s and 30 young pilots. We landed 4 new contracts for Emery Worldwide, and suddenly saw a rash of events in which our DC-3 crews were failing to remove the gear pins before flight. Why did this trend appear after thousands of hours of operation? What changed in our operating environment? Back then we didn’t invest...