From earlier in the thread, I believe someone stated that certification
standards mandate that Go Around thrust is effective within 8 seconds of
throttle application. However, it is usually effective in less time, such as 5
seconds.
That was me - by regulation 95% of go-around thrust must be available 8 seconds after a throttle push from idle. From minimum idle it can take significantly longer, so the engine control incorporates an "approach" idle schedule that is automatically selected when landing flaps are selected. Healthy engines normally do better than 8 seconds from approach idle - typically in the 5 to 6 second range.
There was a infamous story making the rounds back during my graduate study days about a biz jet that landed gear up. The flight crew insisted that the config warning never sounded - until the CVR was played back to them, with the config warning horn blaring during most of final
.
I recall being a passenger on a turboprop years ago in SE Asia (pre 9/11, the cockpit 'door' was a curtain) where I heard multiple warnings going off during final but they continued on and made a fine landing. I think sometimes the flight crews get so accustomed to some of the warnings going off that they simply tune them out - too many audio warnings can be just as bad as not enough.
I suspect the primary focus of the investigation is going to be the human factors element of:
How did the crew fail to engage the autothrottle (and not know it), and
How did the crew fail to notice the falling airspeed until it was too late.