I was out an about in leafy West Yorkshire this afternoon, nowhere near any flight paths really; LBA about 21 miles away; when I heard something I've heard before and often wondered about: the faintish roar of jet engines suddeny becoming audible, then fading back out.

I just wondered if this is simply a change in the wind when a heavy bird happens to be passing or if it could be something else - change in engine thrust perhaps?

As I said, stupid question of the week. Any thoughts appreciated.

Regards.

Hi J2PT. A/c at cruise level don't always produce contrails, and when its quiet, you can hear them, even at the high altitude, but not necessarily notice the aircraft in the sky! A suggestion? - any more?

Rob

Sounds like someone, (engineering), is doing engine runs, or it could just be a jet taking off, how long does the noise stay audible for? Is it always around the same time or does it vary?

I was out an about in leafy West Yorkshire

What, with this wind and rain? [on th'east side ut Pennines anyow]
Could have been a lander...[reverse thrust] Iused to hear Manch landers from 12-15 miles away [in calm conditions]

Could have been some fast jet activity at medium or high level
or some distance away. Sudden high energy manoeuvres
could produce a similar effect to that experienced.

You dont suffer from tinnitus do you ?that condition can cause ghost noises to be heard ,roaring noise in the ears is typical

Im with Rob, where I live is a very quiet location and frequently you can hear aircraft at cruise altitude

BRgds

Course if you're anywhere near Spadeadam........

Could have been someone using a spell of full reverse thrust on landing then reselecting reverse idle.

It can be quite amazing how far the sound carries on light wind, quiet days.

I live near "RAF" Mildenhall and Lakenheath. This effect is very common with the fast, pointy stuff when they turn, but not with the transports & tankers. Based on this you probably heard a military single or twin-engined aeroplane in a turn.


'b

Doesn't Leeds-B have a "slightly" uneven runway, could it be that on the threshold you get the noise carry of the engines being put into takeoff thrust then suddenly stopping as the gradient changes so the noise is deflected elsewhere?

I used to live 7 miles out from Manchester just off the glideslope and Concorde always rumbled the house for about 25 seconds until it disappeared over the camber then returned once it got a few hundred feet in the air!!!

Unmistakeable and missable