Its not the air rush noise, in the recording (which BTW is the lightsaber sound from star wars) its the low whoop...
Have an Airbus driver here from JetBlue, fortunately, there is a pub along the west approach to KSEA, the altitude on the flightpath is around 5500-6000 when the whoop sounds, he says it is when you go to config 1.
We had the ADSB running on the laptop. He pointed out by sound when it was an A320, vs the 737 which just makes an air rush noise...
(not sure about the original FL15-FL12 poster)
Last edited by FlightPathOBN; 27th Aug 2012 at 18:27.