Sonic Boom

[richydraper]

http://www.coventrytelegraph.net/ne...rwickshire-sonic-boom-details-92746-30751429/

apparently a small civilian helicopter sent out an Unlawful Interference distress call early yesterday evening. all sort of rumours were flying about from bombs to fireworks to terrorists you name it, it was speculated about. Anyway it was our QRA boys being given a blank cheque to 'bring it home safely, **** the rules'

an obviously 'well educated, pillock of the community' (read:- Dole Dosser) tweeted this

A ‘false security alert’? What’s serious enough to go above mach 1? More here than meets the eye.”

well lets see, jebend... the fact that an Aircraft squaked '7500' in the year of the queens jubilee and the olympics. Since all eyes are on us anyway this year i think it was a damn sensible decision... let the boys in the Eurofighters break 770mph! if it means the safety of your country who cares about a few civvies being rubbed up the wrong way! theres a hell of a lot of people who would have jumped on the 'why didnt they go supersonic' band wagon if it had turned out to be Ali Bangabba breeching a cockpit of a passenger flight armed with an in'flight plastic knife.

what people fail to realise is that iirc the RAF dont have radar that shows the size of any given airframe they just see a blip usually with a 'reg' number/callsign, altitude and heading info. but no info on the size of the craft. without cross referencing or being in direct contact with the aircraft there is no way of knowing if its a 2-seater cesna or an Airbus A380. and if its sqaking 7500 id be wanting to scramble my best fighters in a hurry too.

Discuss (MEPs favourite)

 

[AndyRKett]

Of course the raf have radar that tell them what the size of aircraft is roughly from its radar cross section as well as the identification transponder fitted to all aircraft (even light commercial craft) which air traffic control can use to instantly identify the aircraft.

Aside from everything you've said I am still very sceptical that this was a sonic boom or an raf euro fighter

Unusually the Mod were very quick to confirm what had happened and all of the papers and new outlets have taken there story to me fact without so much as questioning any detail of the potentially spurious claims. (unusual for the papers to believe anything the government say unless someone is putting the thumb screws on)

I believe their is more to this story, which we will never find out

 

[Dragon Man]

hmm this is strange, we had 2 jets fly over a few days ago creating a sonic boom.

 

[Dominion]

It was a sensible decision, and reassuring to know that we have people in authority with the good sense to make such decisions.
I don't see what the problem is anyway. A sonic boom is extremely unlikely to cause any kind of damage whatsoever, so at worst it makes people look at each other and say 'wtf was that?'
Always better to be safe than sorry

 

[ChrisUK]

 

[richydraper]

Of course the raf have radar that tell them what the size of aircraft is roughly from its radar cross section as well as the identification transponder fitted to all aircraft (even light commercial craft) which air traffic control can use to instantly identify the aircraft.

info from http://answers.yahoo.com/question/index?qid=20061007002821AAgQAhr:-

The old "standard" transponders only return a 4 digit code (mode A) plus the altitude of the airplane (mode C).

The new (mode S) transponders transmit a whole lot more information and their unique code may be attached to a specific plane (you can reassign this number if the transponder is installed in another aircraft).

These transponders not only send the usual 4 digit code, but altitude and TCAS (traffic collision and avoidance system) information and resolution. They will "talk" to other mode S transponders, report the position and if a conflict exists will resolve and may tell the other transponder equipped aircraft to climb while it gives it's own plane a descent command.

Newer technology also transmit GPS position (ADS-B). This information is used to keep airplanes apart even in uncontrolled airspace.


so if the aircraft wasnt fitted with later type transponders then i dont see how a radar blip would offer any info apart from its position, heading and possibly the altitude of the craft given the resolution of primary ground radar over larger distances. maybe im wrong but im just stating stuff from the way i see it.

hmm this is strange, we had 2 jets fly over a few days ago creating a sonic boom.

Thursday around 6 ish? i think this may be the same aircraft

i know for some this is almost unbelieveable and i completely understand that some people will immediately dismiss it as a cover up or untrue and thats fine i have no problems with people having differing opinions or views on stuff. i simply had it on very good authority that fighters were scrambled from lincolnshire around the time of the bang that was heard by people from shropshire, west mids, parts of leistershire, northamptonshire and oxfordshire. what i will ask any of the more skepitcal ones among us is what do you think it was that was heard and reported by so many over such large distances if not a sonic boom accompanied by military jets? and which delta wing military jets would we be using for protection if not the typhoon? (bear in mind we retired our XH558's in '93 )

 

[EvoStevo]

So there was a big bang in the sky, did it cause any harm?

Our air force is on the ball to go and investigate/protect when there is a hijacked helicopter/aeroplane.

Irrespective of the fact that it was an accidental distress signal, there was a quick response from the RAF.

Good on em I say - even though I did not hear it (being at the other end of the country) I would not be concerned about it knowing that they are responding to a potential emergency.

Next we'll be complaining about ambulance sirens

 

[ChrisUK]

There was a good episode on mythbusters about sonic booms. And although loud it's almost impossible to cause damage from a sonic boom. They had to fly at mach 2 at 50ft above the deck IIRC for it to physically break anything.

 

[richydraper]

1540mph 50ft off the kitty litter... braver than i!

 

[AndyRKett]

so if the aircraft wasnt fitted with later type transponders then i dont see how a radar blip would offer any info apart from its position, heading and possibly the altitude of the craft given the resolution of primary ground radar over larger distances. maybe im wrong but im just stating stuff from the way i see it.

You need to do more reading around how air traffic control works, planes and helicopters don't just fly around without ATC knowing exactly who and what's in the air and this includes the raf, they would see the aircraft on the screen, they would know transponder code and from that can gain its tail number, they would be in radio contact and If needs be ATC can prompt a pilot to squak the ident + transponder code to confirm the aircrafts identity.

The code is set at take off by ATC, it generally isn't changed unless there is a problem or fault, ATC would still no what the craft was even if changed because they would have been tracking it.

If the raf didn't know what aircraft were supposed to be in the air how would they identify when there was a more hostile threat? One that wasn't identified and with unknown purpose? these are the craft that the raf send fighters to intercept in an emergency and they occur more commonly than you imagine.

If I can down load an app for my phone which will tell me information on every plane or helicopter I see above my head then the Raf will know the difference between a 172 and an A380

 

[RuSZ]

There was a good episode on mythbusters about sonic booms. And although loud it's almost impossible to cause damage from a sonic boom. They had to fly at mach 2 at 50ft above the deck IIRC for it to physically break anything.

Thats the one with the Blue Angels wasnt it?

i think the only reason it shattered the glass was because it was movement in the shed they put up not the sonic boom itself.

So its perfectly "Safe" and cant beat fast jets :slayer:

The code is set at take off by ATC, it generally isn't changed unless there is a problem or fault, ATC would still no what the craft was even if changed because they would have been tracking it.

I pretty much agree with everything you said, except that statement. ATC dont set anything, Flight Number is set by airline. and the transponder code is unique to that perticular aircraft's transponder unit itself

 

[AndyRKett]

ATC specify what code the pilot is to set on the transponder unit, this can be changed on hand over between ATCs in different areas where one craft might have a very similar code.

The ident is unique to the aircraft, which is stored by the transponder but only broadcast on request
In this instance the Mod state the pilot set his transponder to 7500 which is aircraft being hijacked.