Different types of stall?

[PEI_3721]

BOAC, given that neither we nor the NTSB have knowledge of what the Colgan crew saw, deduced, or ‘deliberately’ reasoned before their actions, there will always be some speculation.
IMHO the NTSB place too much emphasis on what should have seen, monitored, etc; how can anyone know that speed awareness was poor or was there any bias in the reason to pull up – and if so was the bias a flaw in generic stall training or the effect of the crew’s recent (unwarranted) tail stall training.
The NTSB’s findings have the caveat of ‘most probable cause’; many accident investigators shy away from ‘cause’ which might incorrectly focus on one aspect. They also avoid or explain their use of ‘error’.

It would be better to consider the crew as an operational unit, their apparent joint behaviour and documented training history. Why did the PNF raise the flap and the PF pull back; together these appear to be better aligned with tail stall, which is why I used this accident as a simple example to distinguish between the types of stall, the recognition features, and actions required.
A tail stall will not give a stick shake alert (AFAIK), but did the crew know that.

NASA has produced a good training video of tail stall which is predominantly aimed at GA flying. Unfortunately many commercial training sessions take easily available off-the-shelf materials and use them without further thought as to their relevance to aircraft type or operation. Tail stall is now much less relevant to commercially certificated aircraft which have been subject to new rule making; the icing test requirements have been strengthened with considerable focus on conventional stalling and stall warning. AFAIR the Q400 had considered many of these aspects.

AFAIK the last commercial aircraft subject to tail icing was the J31; all of these aircraft were modified to restrict the configuration associated with the conditions; or has anyone more recent information.