Anyone else hear loud 'bomb-dropping' sound at night?

[Ronnijade]

Like a high pitched whistle that quickly gets louder and decreases in frequency. Just heard it while having a drink with my friend and it's scared the living daylights out of us at first! Genuinely sounds like a bomb or asteroid falling from the sky, very loud! Anyone else hear this/have an explanation or am I just going crazy?

[Elphinstone's Army]

We are on CPR and heard this, a plane coming over - sounding low - they change gear over Barry Road,

all gone now.

[Ronnijade]

Bloody loud planes! Almost gave me a heart attack! Lol

[Tractorlad]

Likely a BAe146 Avro RJ type aircraft flying into City Airport. The high mounted wings on these type of aircraft cause a diving type noise as the flaps are lowered for landing. As this happens on approach and the flight path is over ED this can this can appear loud in the neighbourhood

[ianr]

London City Airport is very unlikely: their permitted operating hours end at 22:30. https://www.londoncityairport.com/aboutandcorporate/page/noiseandtrackkeepingsystem https://www.acl-uk.org/wp-content/uploads/2016/10/LCY-S17-Capacity-Declaration.pdf.

I guess a Heathrow private or cargo flight is the most likely candidate. Or an alien craft.

[kford]

It's the BaE/Avro 146s extending flaps for landing.

[alex_b]

What time was this? I had a look at flightradar24 and the only thing I could see coming over us was a Qatar Cargo plane (Houston to Liege) at 35,000 feet at 12:08am Saturday morning.

If you're searching yourself, note the flightradar uses UTC so is an hour behind BST.

[Ronnijade]

alex_b Wrote:

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> What time was this? I had a look at flightradar24

> and the only thing I could see coming over us was

> a Qatar Cargo plane (Houston to Liege) at 35,000

> feet at 12:08am Saturday morning.

>

> If you're searching yourself, note the flightradar

> uses UTC so is an hour behind BST.

Then that would be the culprit! Thank you very much!!!

[hertburs]

I find it very difficult to believe that a plane flying at nearly 7 miles high would sound like this. Not all planes appear on Flight Radar as far as I am aware.

[alex_b]

The don't all appear in all areas, but it's pretty reliable in London I think. I do find it odd that a plane flying so high would be that noisy though.

[Ruskin]

As Kford says, it's a 146 lowering its flaps as part of landing checks a few thousand feet above (I took in its route-proving in the mid-80s, the first time it was noticed outside BAe) but not one at a cruising altitude when flaps are retracted. I hear it all the time over us near Denmark Hill and see it on Flightradar. It is unnerving when you don't know what on earth it is!

[ianr]

I agree with Hertburs on both points.

The BaE 146 (later, Avro RJ100) suggestions seem very plausible. Some google searching for BAe146 flaps sounds shows that it's long been a talked-about phenomenon. One example is at http://www.youtube.com/watch?v=RNZ92B7QsOA. A sound snippet from it is attached. I think it may be just the external manifestation of the maybe even scarier sound within the plane when the flap movement is actuated.

[Jeremy]

I've often heard that falling pitch, "dive-bombing" sound very early in the morning. I'm not often disturbed by planes, but in the warmer weather with the windows open, it's pretty noticeable. As Ruskin said, a little unnerving at first!

If the noise is a plane lowering the flaps... is it the sound of the motor? Some aeroacoustic phenomenon? Is the falling pitch due to the Doppler effect?

[alex_b]

But Ronnijade and Eliphinstone's Army both said it was around midnight on Friday/Saturday. I can't think where a BaE146 would be landing at that time of night and why it wouldn't show up on flightradar.

[lavender27]

It was 4th July after all.

[prit]

I heard it! Last night​ (Friday) but couldn't give a time as I was half asleep.

I was sceptical when I read the op, having only previously heard the lower 'gear change' noise but yes, this sounds like a high whistle, would have been worrying had I not seen this post!

[Ronnijade]

prit Wrote:

-------------------------------------------------------

> I heard it! Last night​ (Friday) but

> couldn't give a time as I was half asleep.

>

> I was sceptical when I read the op, having only

> previously heard the lower 'gear change' noise but

> yes, this sounds like a high whistle, would have

> been worrying had I not seen this post!

Rather unnerving, right?!