Can a Sonic Boom Be Heard For A Distance Of 100 Miles? If Not Something Funny Has Happened.

At 18.10 BST (British Summer Time) a large boom was heard as far away as Coventry in the West Midland and Bath in Somerset. That is a distance of around 100 miles. The M.O.D. has stated it was the sonic boom from a Typhoon jet fighter. So the question is, can a sonic boom be heard over that distance. Also some people stated their windows in their homes rattled.

Story here:-

www.bbc.co.uk...

Mods if i have put this on the incorrect forum then please move.

A sonic boom is not a one off effect, it will be heard by anyone under/near the plane for the entire time its supersonic.

If a jet takes off and goes supersonic over land (BIG NO NO) the boom and the planes engine sound will be heard anywhere it goes, for example takes off in London goes supersonic upto Scotland, the "boom" will be heard by everyone in between those places.

reply to post by Biigs


Yes, but it wouldn't rattle or shake windows. This scenario was actually tested by flying a jet over a house to see the effects.

I found this...it was on wikipedia but it is backed up with sources...

The intensity and width of a sonic boom path depends on the physical characteristics of the aircraft and how it is operated. In general, the greater an aircraft's altitude, the lower the overpressure on the ground. Greater altitude also increases the boom's lateral spread, exposing a wider area to the boom. Overpressures in the sonic boom impact area, however, will not be uniform. Boom intensity is greatest directly under the flight path, progressively weakening with greater horizontal distance away from the aircraft flight track. Ground width of the boom exposure area is approximately 1 statute mile (1.6 km) for each 1,000 feet (300 m) of altitude (5 m/m); that is, an aircraft flying supersonic at 30,000 feet (9,100 m) will create a lateral boom spread of about 30 miles (48 km), or at 10,000 meters a spread of 50 kilometers. For steady supersonic flight, the boom is described as a carpet boom since it moves with the aircraft as it maintains supersonic speed and altitude. Some maneuvers, diving, acceleration or turning, can cause focusing of the boom. Other maneuvers, such as deceleration and climbing, can reduce the strength of the shock. In some instances weather conditions can distort sonic booms.

Source: USAF Fact Sheet 96-03, Armstrong Laboratory, 1996

So using this data it would have to be flying at around 93,000 feet to be heard 100 miles away hahaha!!

Hi I live in Coventry and we thought there had been an explosion.
It was really loud it was all over Facebook immediately with rumours rife, everything from meteors to earthquakes being blamed.

According to the m.o.d it's sonic booms as stated by the op.
Thought I'd post this link that contains eye witness report of the aircraft responsible .......
www.bbc.co.uk...

Crazy isn't it. Over all those counties? And such is weird that 4 minutes before the UK had a small Earthquake. WTF!

Earthquake at 18:06 news.bbc.co.uk...
"Sonic Boom" at 18:10 www.bbc.co.uk...

Clarity is needed - what were they sending Typhoons to? If a Helicopter sends a distress signal, why would they send jets? I thought jets deal with air threats. I'm sure it's legit, just strange IMO. I didn't hear anything in South Oxon though, definitely didn't hear any passing jets.

reply to post by Vandettas


It TOTALLY does shake windows, its a sudden change in air pressure EXACTLY the same as a bomb going off, it sends out a compressed pressure wave.

Originally posted by Vandettas
reply to post by Biigs

 

Yes, but it wouldn't rattle or shake windows. This scenario was actually tested by flying a jet over a house to see the effects.

According to Nasa they can?

Quietlike: Do sonic booms really have the potential to bother people that much? I mean, does the aviation community believe there might someday be enough supersonic aircraft in the air that it would be a pain to people?

Ed.: Right now there are sonic booms around military bases, and some of them are very loud. They can be startling. If the airplane is very low to the ground, it can break windows. The very low altitude supersonic flights are done in very remote areas. These future low boom aircraft should be very quiet and be able to fly anywhere around the world.

www.nasa.gov...

also more in this link:

www.nasa.gov...

Overpressure
Sonic booms are measured in pounds per square foot of overpressure. This is the amount of the increase over the normal atmospheric pressure which surrounds us (2,116 psf/14.7 psi).

At one pound overpressure, no damage to structures would be expected.

Overpressures of 1 to 2 pounds are produced by supersonic aircraft flying at normal operating altitudes. Some public reaction could be expected between 1.5 and 2 pounds.

Rare minor damage may occur with 2 to 5 pounds overpressure.

As overpressure increases, the likelihood of structural damage and stronger public reaction also increases. Tests, however, have shown that structures in good condition have been undamaged by overpressures of up to 11 pounds.

Sonic booms produced by aircraft flying supersonic at altitudes of less than 100 feet, creating between 20 and 144 pounds overpressure, have been experienced by humans without injury.

Damage to eardrums can be expected when overpressures reach 720 pounds. Overpressures of 2160 pounds would have to be generated to produce lung damage.

Typical overpressure of aircraft types are:

SR-71: 0.9 pounds, speed of Mach 3, 80,000 feet
Concorde SST: 1.94 pounds, speed of Mach 2, 52,000 feet
F-104: 0.8 pounds, speed of Mach 1.93, 48,000 feet
Space Shuttle: 1.25 pounds, speed of Mach 1.5, 60,000 feet, landing approach

reply to post by markymint


I hadn't seen the report about the earthquake at 16.04 BST. Because of the timings and locations they may well have a connection. I am in Birmingham about 16 miles north of Coventry. I heard or felt nothing.

I think people are misunderstanding this and the OP. Yes, sonic booms are heard roughly under the flight path of a plane travelling above the speed of sound, for as long as it is doing so, be that 100 miles or 1,000 miles.

What the OP is, I think, alluding to is the fact that if the Typhoon jets took off from their QRA duty at an Oxfordshire base (Brize Norton?), and they flew to the area around Bath (which is where the MoD claims the incident happened with the helicopter) then why was the 'sonic boom' heard, and felt, almost 100 miles north, in Coventry, and also in Staffordshire (even further north. I live in the West Midlands and it has been on the local news)?

The point is that the official explanation seems very suspicious. Go to Google Earth and you will see what I mean. If the jets were responding to a helicopter emergency around bath then they would have had a short, fast, and relatively low-level dash of only around 50 miles to get there. Would they have needed to go supersonic for 50 miles? Even if they did then why would the residents of Coventry and around Staffordshire have heard this? Even if the jets flew over those areas after the incident then surely they would not have been flying supersonic after it. They would only have been authorised to fly supersonic for the emergency situation.

Please, just go to Google Earth and explain it. I'd love to understand how this makes any sense.

Originally posted by markymint
Crazy isn't it. Over all those counties? And such is weird that 4 minutes before the UK had a small Earthquake. WTF!

Earthquake at 18:06 news.bbc.co.uk...
"Sonic Boom" at 18:10 www.bbc.co.uk...

Clarity is needed - what were they sending Typhoons to? If a Helicopter sends a distress signal, why would they send jets? I thought jets deal with air threats. I'm sure it's legit, just strange IMO. I didn't hear anything in South Oxon though, definitely didn't hear any passing jets.

edit on 12-4-2012 by markymint because: fix errors

The earthquake link is from 2008.

Page last updated at 07:27 GMT, Monday, 27 October 2008

Only time I have ever heard of the sonic boom being heard hundred of miles away is when the space shuttle re enters earth atmosphere. This can only be achieved by flying at high altitude.

Originally posted by markymint
Crazy isn't it. Over all those counties? And such is weird that 4 minutes before the UK had a small Earthquake. WTF!

* Earthquake at 18:06 news.bbc.co.uk...
"Sonic Boom" at 18:10 www.bbc.co.uk...

Clarity is needed - what were they sending Typhoons to? If a Helicopter sends a distress signal, why would they send jets? I thought jets deal with air threats. I'm sure it's legit, just strange IMO. I didn't hear anything in South Oxon though, definitely didn't hear any passing jets.

edit on 12-4-2012 by markymint because: fix errors

OP Haha did you actually bother to look at the date of the report for the *Earthquake? this reports from the 2008 quake ?

Anyone explain the basic glaring elephant in the room? Why would the 'sonic boom' be heard and felt almost a hundred miles away from the flightpath? Brize Norton, Oxon, to Bath is just a little straight line - no complex routing required. How on earth could the sounds and shaking in Coventry and Staffordshire be explained?

I believe the sonic boom report is a cover up.
I just looked right now on the bbc website, travel, and EVERY airport in the UK is disrupted
Not taken a screen cap, but this isnt normal
bbc airport status

Connected?

Edit: apologies, I have just noticed my link is not a proper list of all flights, but just a list of flights suffering delays.
So not such a bad situation as I thought

Originally posted by djyorkie
I believe the sonic boom report is a cover up.
I just looked right now on the bbc website, travel, and EVERY airport in the UK is disrupted
Not taken a screen cap, but this isnt normal
bbc airport status

Connected?

Not sure that is really anything to worry about. That airport thing is referring to individual flight delays - not whole airports being disrupted. This is pretty normal.

reply to post by OliArtist


The next question to ask is, why would RAF Typhoon jet fighters be responding to a civilian helicopter emergency call?

Its really interesting how everyone seems to be swallowing the official line despite the fact that there is still the massive, glaring geographical anomaly. People just aren't mentioning it.

Warwickshire Fire and Rescue Service and West Midlands Police in Coventry were inundated with calls about this. Its not like it was just heard faintly in the distance or anything. But why would the jets have gone anywhere near Coventry if they were 'rushing' to Bath for an 'emergency'?

Please, someone address this.

reply to post by alldaylong



Apparently they thought it was hijacked. It is interesting to consider the following though:

If you were going to devise a cover story you would naturally first think of saying a commercial airliner was having a hijack incident. This would be most believable to the public - of course you would send up the QRA fighters - that's what they are there for after all. But there is a problem with that. It would be easy to prove that there was no such incident. Civilian air traffic chatter is monitored by all sorts of people, plus you have civilian crews and passengers involved. But, a helicopter - fantastic. Helicopters fly low enough that they don't need flight plans etc and are not normally subject to much ATC rules etc. Its easy to just say there was a small civilian helicopter in trouble (or indeed to put one up there to put on a show).

This would also explain the 2 hour delay it took the MoD to realise that 2 of it's QRA fighters (of which there are only a handful at any one time on duty) had been scrambled! Of course they were just using the time to concoct a story. But they completely missed the bit about explaining why Coventry (and other places further north) were affected by the 'sonic boom'.

Originally posted by OliArtist
Anyone explain the basic glaring elephant in the room? Why would the 'sonic boom' be heard and felt almost a hundred miles away from the flightpath? Brize Norton, Oxon, to Bath is just a little straight line - no complex routing required. How on earth could the sounds and shaking in Coventry and Staffordshire be explained?

I don't think they came from brize. There's been no reports of any fighter movement there today that I've seen, I monitor the plane spotting forums quite a lot and people go to brize every day. Someone would have seen them scramble...