A320 family sometimes make an odd howl occasionally: sounds rather like blowing across the mouth of a milk bottle and otherwise pretty much as Rainboe describes. I hear it most often as the aircraft has come off the hold at Biggin, heads west towards Ockham then turns back for a 27 approach into Heathrow.
I was on an EasyJet A319 landing at Gatwick several years ago, sitting just aft the wings and thought I could hear it faintly as the flaps began to extend, so they might be the culprit.
PS, would you have flaps coming down that early, off the hold at Biggin?
The landing at Gatwick (from Edinburgh) was more or less straight in, we flew west of Guildford, the flaps were starting to extend before we passed Dunsfold for a landing on 08 as I recall.
Last edited by treadigraph; 18th Aug 2008 at 12:14.