Interception communications

[Phil_R]

Hi folks

When two Typhoons intercepted a Latvian cargo aircraft in 2014, the Typhoon pilot began a radio transmission with "one six zero five from lima nine tango four seven..."

How does the cargo plane they're intercepting know he's 1605? From what I can find online, it was an Antonov with the registration code YL-RAA.

Also, how does the cargo plane know that L9T47 is the Typhoon? That doesn't sound like a UK military callsign.

It's nothing but idle curiosity, but where do these codes come from?

P

[charliegolf]

A cargo ac that stopped responding/ left an airway? The cargo doesn't need to know it's mil, but suspect after acknowledgement, they'd be told.. They will find out soon enough if they don't.

CG

[Cyberhacker]

To be honest, I'm surprised that a standard set of callsigns are not used... akin to RESCUE xxx that were (assume still are) used for noduff emergency flights...

[KiloB]

Suspect that 1605 was the Antonov’s ADS Squawk code.

[MPN11]

Never been involved, but something a bit more that "1605" seems constructive ... "Antonov squawking 1605 this is interceptor L9T47" might be a good start, to give them a clue about the disembodied voice in their headsets. Cryptic, clipped, Mil R/T might work with the 'mates' on frequency, but dealing with foreigners requires a little more to achieve 2-way. Done a fair bit of non-standard comms in my ATC time when controlling other Nations, especially non-English native speakers.

[sycamore]

More likely to be the company `flight number`....

[Pontius Navigator]

As MPN says, you need to communicate. After several attempts to follow our briefed procedures "We are RAF 4 Jet" the French controller came back with "Are you VULCAN X-RAY MIKE 607?"

Seemed quite explicit and reinforced by two FAF Mirage on port wing supported by two RCAF F104 on the other.
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[MPN11]

I recall being quite annoyed by someone on the RT in Singapore calling himself a Twin Turbo ... it was a bloody wallowing Belvedere!!

We had enough trouble weaving Lightning, Mirage, Hunter, Canberra and Single Pioneer in the system without that! :*

[SirToppamHat]

Hi folks

When two Typhoons intercepted a Latvian cargo aircraft in 2014, the Typhoon pilot began a radio transmission with "one six zero five from lima nine tango four seven..."

How does the cargo plane they're intercepting know he's 1605? From what I can find online, it was an Antonov with the registration code YL-RAA.

Also, how does the cargo plane know that L9T47 is the Typhoon? That doesn't sound like a UK military callsign.

It's nothing but idle curiosity, but where do these codes come from?

P

Lima Nine Tango Four Seven (flying with 46 or 48 as the other half of the pair I presume) sounds precisely like a UK operational military callsign. These are issued according to centralized procedures and are based on the unit rather than the squadron - in my experience one number and 2 letters with the digit first or second. So Nine Lima Tango or Lima Nine Tango would be OK, but not Lima Tango Nine. In effect, the trigraph is issued at random ... the station/squadron/unit has no say ... as far as I know, they do not repeat regularly (though I guess statistics will suggest that there are only 26 x 26 x 10 x 2 possible combinations), .

Can't speak for the 1605, it could be part of the callsign (commercial and military aircraft don't often use their tail letters/registrations as their callsigns though it is common in the General Aviation world) - have a look at any ADSB feed for plenty of examples. As MPN11 says and Pontious Navigator agrees, I would expect the call (especially the initial call) to be as precise as practically possible and the form of words is very formulaic. So "Aircraft Squawking 1605" or "Ukraine Air Force 1605" or the whole callsign.

Toppam. .

[Phil_R]

Lima Nine Tango Four Seven (flying with 46 or 48 as the other half of the pair I presume) sounds precisely like a UK operational military callsign. These are issued according to centralized procedures and are based on the unit rather than the squadron - in my experience one number and 2 letters with the digit first or second. So Nine Lima Tango or Lima Nine Tango would be OK, but not Lima Tango Nine. In effect, the trigraph is issued at random ... the station/squadron/unit has no say ... as far as I know, they do not repeat regularly (though I guess statistics will suggest that there are only 26 x 26 x 10 x 2 possible combinations), .

OK, thanks folks! But:

How does this relate to the sort of stuff you hear along the lines of [word] [number] [number]? The famous example is "bravo two zero" and seems to be used by all branches, but I hear it endlessly in recorded radio traffic. One example contains a conversation during (I think) a Red Flag exercise during which an American controller of some kind is "alleycat," and talks to a British voice describing himself as "hydra one one." Other players include what I assume is a tanker "focus," though we occasionally hear from "focus three eight," and what sounds like a fast jet called "knight four one."

Is this some sort of American procedure because it's Red Flag?

Transcript of one exchange, most of which I do vaguely follow, is in the hidden block below for reference.
KNIGHT41: Knight four one checking in as fragged minus one
ALLEYCAT: Knight four one, alleycat, negative radar contact, procedural control only, maintain own separation, altimeter two niner niner niner, pull up clear of clouds, few clouds in east, flight level two six zero to three one zero, west side is clear, words alpha, chalice nogo, checkmate nogo, words bravo, single frequency war on beige three zero.
KNIGHT41: [unclear] copied, words bravo, single freq war beige three zero, Knight four one.
ALLEYCAT: Knight four one, Alleycat, push tactical.
KNIGHT41: Push tactical, Knight four one. [break] Knight, push tactical.

[biddedout]

I think I head this interception on 121.5 and remember the Typhoon pilots sounding a bit excited and unnecessarily shouty. Particularly when they rattled out the arse covering lawyery bit about needing to shoot down for Queen and country. I guess the Antonov pilot had already got the hint from two jets on his nose and was probably wishing he had a copy of the intercept procedures to hand. I seem to remember (if it was this incident) he did respond but I don't think his English language skills were up to picking up on the punchy clipped top-gun stuff.

[Old-Duffer]

MPN11,

Re Post 8, the Belvedere did not WALLOW but proceeded gracefully across the skies until the control cables jumped off their pulleys or the vertically mounted engines started and dumped a bucket of Avpin on your shiny shoes!!

Old Duffer

[Widger]

Dear Phil R,

You do realise that you have now committed an offence under the Interception of Communications Act 1985?

[MPN11]

MPN11, Re Post 8, the Belvedere did not WALLOW but proceeded gracefully across the skies until the control cables jumped off their pulleys or the vertically mounted engines started and dumped a bucket of Avpin on your shiny shoes!!
Old Duffer
I apologise for any disrespect shown to Bristol's Finest Tandem-Rotor Torpedo Carrier! IIRC I was busy on Director at the time, and thus temporarily less tolerant than my usual mellow self.

A bit like the visiting Victor tanker joining the traffic pattern at Tengah, where there were lonnggg delays in responding to, and copying with, my RT instructions. Eventually I went non-standard, as said "May I speak to the Captain, please?" A new voice materialised, and stayed with me for the rest of the recovery process. :cool:

[Wyler]

The air to air comms are not the only conversations going on. There would be a lot of landline stuff as well between different control authorities.
biddedout - The 'arse covering lawyery bit' is the most important bit of all :)

[Phil_R]

You do realise that you have now committed an offence under the Interception of Communications Act 1985?

I doubt it; that act was (actually quite famously) replaced by RIPA, although I guess similar rules might apply.

Still, as a practical matter, there's hours of it available; just google for "red flag scanner audio." I would humbly submit that if it's a serious security issue the stable door has been swinging in the breeze for years.

Does this mean nobody's going to want to address how the [word] [number] [number] callsigns work?

P

[ORAC]

https://www.pprune.org/military-aviation/605452-raf-vulcan-callsigns-1970-s.html#post10059596

The entire thread is relevant.

[Phil_R]

https://www.pprune.org/military-aviation/605452-raf-vulcan-callsigns-1970-s.html#post10059596

The entire thread is relevant.
Many thanks. What I'm getting from this is that everyone has something formal in the format A1B23 where the first three are randomly assigned and the last two indicate an aircraft, and also something else in the format [word] [number] [number], which may be based on all kinds of things. It's not quite clear to me at what time either of those would be used. Almost all of the military communications traffic I've ever heard has been "knight four one" or "focus three eight," that sort of stuff, though it is very often in an American context.

(Oddly enough, "knight" probably isn't one I'd use in fictional writing, because it sounds too... you know... top gun?)

[frodo_monkey]

Many thanks. What I'm getting from this is that everyone has something formal in the format A1B23 where the first three are randomly assigned and the last two indicate an aircraft, and also something else in the format [word] [number] [number], which may be based on all kinds of things. It's not quite clear to me at what time either of those would be used. Almost all of the military communications traffic I've ever heard has been "knight four one" or "focus three eight," that sort of stuff, though it is very often in an American context.

(Oddly enough, "knight" probably isn't one I'd use in fictional writing, because it sounds too... you know... top gun?)

Not quite true. One callsign per aircraft. For UK operational use (such as QRA etc) you’ll have an A1B23 style callsign where A1B23 is the formation lead and A1B24 is the wingman (providing it’s a formation).

For training sorties, a singleton is likely to have a Stn identifier plus pilot identifier - for example ‘Marham 01’ will be a Marham based aircraft, and 01 a pilot from Marham (normally the Stn Cdr in 01).

Formations will normally use a formation callsign - allocated to a particular Squadron - plus a numerical identifier corresponding to a place within the formation. So ‘Vandal 2’ would be the no 2 in Vandal formation - Vandal being a 617 Sqn callsign (or at least it was in Tornado times). Some variations on this theme, so if there were two Vandal formations launching in a day the first four might be Vandal 11-14, and the second 4-ship Vandal 21-24 etc.

For ops outside the UK you’ll use an Air Tasking Order callsign for your formation, but the number convention above applies. So you might be tasked as ‘London’ formation for example, and also given the callsigns 71 through 74 depending on what else had gone on.

[Phil_R]

Formations will normally use a formation callsign - allocated to a particular Squadron - plus a numerical identifier corresponding to a place within the formation. So ‘Vandal 2’ would be the no 2 in Vandal formation - Vandal being a 617 Sqn callsign (or at least it was in Tornado times). Some variations on this theme, so if there were two Vandal formations launching in a day the first four might be Vandal 11-14, and the second 4-ship Vandal 21-24 etc.

Thanks. That's how I understood it; that's how I'd always approached stuff when these aircraft were supposed to be on actual operations.

[Widger]

Quote:
Originally Posted by Widger View Post (https://www.pprune.org/military-aviation/638673-interception-communications.html#post10990943)
You do realise that you have now committed an offence under the Interception of Communications Act 1985?
I doubt it; that act was (actually quite famously) replaced by RIPA, although I guess similar rules might apply.

Still, as a practical matter, there's hours of it available; just google for "red flag scanner audio." I would humbly submit that if it's a serious security issue the stable door has been swinging in the breeze for years.

Does this mean nobody's going to want to address how the [word] [number] [number] callsigns work?

Tell it to the judge!