Forums

Posted: 20-07-2013 07:45 Post subject:

Right - me mate replied on the hoof (he's away too) so it's shortish:

"It's hard to tell what sort of plane by noise alone, because at distance the higher pitches fade but the low pitches carry a long way and most jet engines have a similar overall noise. From far away a Tornado doesn't sound very different from an Airbus, it's only up close you can hear the difference. That part of UK is probably fighters taking off and landing and flat topography means you won't necessarily see them but you'll hear them for miles, it can be hard to gauge where deep noises come from, and the sound can bounce around buildings and hills produce weird effects as the plane flies by which is why they can suddenly sound very loud then very quiet, its generating the same consistent noise at source but the echoes distort it. There are a few commercial flightpaths over there but no major airports close by so airliners would be high up and quite visible so I'd say it is military over the horizon."

The odd syntax is all his Smile

.

Posted: 20-07-2013 11:34 Post subject:

What odd syntax?

Posted: 20-07-2013 13:40 Post subject:

Posted: 21-07-2013 08:44 Post subject:

I often get low flying planes, because the RAF practice around here. The jet fighters can be difficult to see, because the plane is ahead of its sound, so to speak, so one instinctively looks in the wrong place.

But even though they are very low - well below the mountain-tops - they do make the distinctive Doppler effect, and if there is more than one (they are usually in pairs)you can clearly distinguish each one as it goes by.

I used to live right next to an airport, and occasionally you would hear engines being tested by being run at full bore for some minutes, but even though we lived within a hundred yards or so of the end of one of the runways, that was never as loud as a take-off. But these were civil aircraft, in the main.

Loudest noise ever - visiting Vulcan taking off on 'our' runway and doing a sharp turn - apparently standing on one wing-tip - right over our heads. We were gardening at the time. Brilliant. And sure did upset all the nimbys who'd bought a house next to the airport and started complaining about the noise. (I'm not a plane enthusiast, we bought the house because we could afford it - it was cheap because it was next to the airport. And a main road. And a railway. And therefore obviously subject to noise.)