Three Bars, note the word
PRIOR
when flying under daylight VMC conditions prior to an obstacle or terrain warning
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PRIOR to the warning. How do you know what has set it off. I was once told of United airlines Jumbo flying underneath a QF jumbo in IMC (prior to TCAS). The UA jumbo did not maintain its altitude and came close to the underside of the QF one at 20000 odd feet setting the QFs GPWS off.
Now admittely its an unlikely scenario that a light a/c or some other object other than terrain would do this, but imagine you have just set up for approach, then told to Go around, mid go around you get a GPWS - which I dont think you could be expecting, nor with the high nose attitude can you see underneath you...... Would not the most conservative course of action be to carry out the GPWS maneouvre - especially seeing the emphasis being placed on it in QF training at the moment?
Anyway its all speculation, does anyone actually know the facts?