Thanks all for the interesting comments so far. If I could just second BOAC's request to avoid rehashing here arguments that have been thoroughly played out in the respective accident threads. My purpose in starting this thread was to look at the
different attitudes to the actions of the respective crews in the two accidents, and to explore what this might show about underlying beliefs and assumptions about human factors and safety.
Anyway, so far we have:
Both Type 3 mistakes. IMHO.
According to your definition both are type 2 mistakes in my opinion
So much for the PPRuNe consensus! But still, it seems that many view the two errors as being of the same type. As PJ2 says, my types are at best approximations and at worst completely arbitrary. But this kind of rough categorisation can perhaps shine some light on the difficult cases at the margins - which are typically the ones that result in accidents. As captplaystation puts it:
teetering between Type 2 & 3
For example, type 2 errors that are insufficiently covered by checks and balances, or type 3 errors that are easier to make and more common than is generally recognised.
As SLF, I am happy to accept the tiny risks of catastrophic mechanical or structural failure, extraordinarily unlucky combinations of multiple factors (e.g. crew forgets flaps AND flap warning fails), freak weather, terrorist attacks, midair collisions, etc. What worries me more is that I may be a typo away from a fiery death, or that the crew may just "forget" to fly the plane.
Worse than this, if I have understood correctly, is that there's no agreement on what to do about the problem. PJ2 says of the TK crash:
Further, there is no understanding in this accident that is useful in the addressing of organizational, systemic or human factors accidents.
So what to do? Are you saying these kinds of risks cannot be reduced?