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Old 25th Mar 2015, 15:06
  #655 (permalink)  
Bleve
 
Join Date: Jun 2006
Location: Terra Firma
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Explosive decompression is a near instantaneous as you will get. As suggested, on a large aircraft you would not expect explosive decompression from loss of cabin Windows etc.
The 2008 Qantas event is informative. When cruising at 29 000' (cabin altitude 3 700') an oxygen bottle exploded creating a 3 square metre hole in the fuselage. One second later the A/P disconnected and the aircraft pitched nose UP. Three seconds later the cabin altitude reached 10 000'. Pilots put on oxy masks and established communications with each other. At 22 seconds descent was initiated (thrust to idle/ speed brakes extended). At approx 40 seconds the uncommanded climb was reversed and and the descent established, maximum cabin of 25 900' occurred at about this time. The mean rate of descent was about 3 000 fpm and the cabin altitude was about about 3000' below the aircraft's altitude during the descent.

The key points are that at 29 000' and with a 3 sq m hole, cabin altitude reached 10 000' within 3" and 26 000' within 40". With idle thrust, speed brakes extended snd IAS at the cruise IAS, descent rate was ~ 3 000 fpm.
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