Andrewg - the performance of the human in the loop is one of the most difficult things to predict. In the case of AF 447, they wre presented a difficult challenge, and for a variety of training, cultural and engineering reasons, failed to meet that challenge. In the case of Al Haynes of UAL flight 232, he flew an airplane with all hydraulics failed, and got it to the runway in Sioux City, IA
In general, if a pilot is trained for it, has seen it in the simulator before he sees it in the airplane, then that pilot is very likely to handle it successfully.... Loss of indicators and displays is trained...so that failure, in and of itself, is unlikely to cause a crash, though the workload on the crew increases dramatically with a loss of displays.
One of the biggest areas of safety innovation is the introduction of Cockpit Resource Management - leadership, by another name....developed by United and known as C/L/R in the company... The resources include the skills, experience, knowledge of the crew in the cockpit and external resources, such as Air Traffic Control, Cabin Crew, and Company communications such as the Dispatcher. The ability of a crew to optimize their performance by managing those resources effectively is critical to a successful outcome in an emergency. Al Haynes demonstrated brilliant resource management of the situation, including leveraging an instructor who was in the back, directing and querying ATC and communicating, prioritising and distributing tasks among the crew.
Clearly, some pilots are better than others, and some companies train pilots better than others...but despite that variability, the error rate that results in a crash is so low that it is difficult to convince the bean counters that advanced pilot training (like United's 3 day immersion course in C/L/R) is worth the investment.
Fortunately for the flying public, the pilot's unions have been able to press for the implementation of better training, like the upset training I referred to in the previous post, or United's C/L/R, at the more enlightened airlines (and there are many good airlines out there)...after all, the cockpit crew is among the least likely to survive an airplane crash...while the bean counters will get in their luxury car and drive home from the office after their airline loses an airplane...
Cheers,
Astro
