Propulsion Control of Aircraft: A Case Study in Systems Engineering

摘要

On July 19, 1989 United Airlines Flight 232 was cruising at approximately 37,000 feet between Denver and Minneapolis when it experienced a catastrophic failure of the number two (tail-mounted) engine. At the moment of failure are engine ejected shrapnel through the tail section, destroying all three on-board hydraulic systems. The complete loss of hydraulics left the pilots of the McDonnell Douglas DC-10 aircraft without the ability to move the flight controls. In contrast to what most aviation experts would have expected as an outcome, the airplane was crash-landed at Sioux City, Iowa with 185 of the 296 passengers and crew surviving. The flight crew was able to maintain rudimentary control of the aircraft with only the use of thrust from the two remaining wing-mounted engines by independently moving their respective power levers. It was not until the final touchdown that the crew's command of the aircraft was lost due to the imprecise nature of manual propulsion control (Propulsion Controlled Aircraft (PCA), 1999).