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Jump Complete
3rd Jul 2005, 08:50
Flying a Islander I was warned by the ATSU providing a RIS of 'fast moving' traffic etc. It was a pair of Canberras which I estimated at around 200 kts. Obviously a bit faster than I was doing in the Islander but lead me to wonder. Is there a diffinitive speed for issuing a 'fast moving' advisory or is it relative to the respective aircraft. (Presumably the same applies to 'Slow Moving'?

Spitoon
3rd Jul 2005, 09:57
No definitions that I'm aware of. A controller often has no way of determining the groundspeed of a target so it's usually a subjective judgement to give the pilot being told about the traffic an ideaof whether to look out for military jet or a microlight.

Lon More
3rd Jul 2005, 10:25
a pair of Canberras which I estimated at around 200 kts. At the sort of altitudes Islanders operate at I would say anything over about 180 knots is fast moving.

Spitoon The afterglow, or track history, on the radar gives a pretty good idea of the speed; also most modern systems will also display ground speed.

edited for spelling errors

Spitoon
3rd Jul 2005, 15:21
Ok, maybe I should have said that controllers often have no way to accurately determine the groundspeed of an aircraft from the radar.

The target trail can give an indication of speed but can also be misleading (and if you're relying on radar data only, even the g/s readout can be misleading with some manoeuvres). Depending on the type of processing and display the controller can sometimes also make an educated guess at the type of aircraft from the 'strength' of the return.

Pierre Argh
3rd Jul 2005, 18:41
spitoon

sorry wrong again... Ok, maybe I should have said that controllers often have no way to accurately determine the groundspeed of an aircraft from the radar

the actual ground spped of a squawking radar contact is just a "right click" away.... air speed is another matter though?

To me, "fast moving" tends to mean significantly faster than you". In a Canberra it'd need to be fighter speed, but in a C172 it could easily be a Canberra... it's all relative.... much like "slow moving"

G-ANDY
3rd Jul 2005, 18:50
TWO Canberras as the same time - thats quite rare nowadays! Was over at Marham the other day and had a tour of the Canberra hangar - two grounded, one poorly and two flying in the UK and some off taking photos!!

BALIX
3rd Jul 2005, 19:01
the actual ground spped of a squawking radar contact is just a "right click" away

Not necessarily. Had Jump Complete been flying his Islander in Scotland and receiving a RIS from ScACC, the controller would not have that facility.

Still, only a few years till the new place opens...

Cuddles
4th Jul 2005, 07:17
Significantly faster than you, we often get enough information from the aircrafts behaviour and SSR code to make an educated guess,

ie if it's being a bloody nuisance, there's a good chance it's an F15.

Spitoon
4th Jul 2005, 07:39
the actual ground spped of a squawking radar contact is just a "right click" away.... Pierre, I'm really not into point scoring between ATC units. If you take the trouble to visit a few other units you might be surprised to find that not everyone has a 'click' or speed vector facility.

Widger
4th Jul 2005, 09:08
Getting back to the main point. The controller concerned obviously had a bit of nouse about him and called "fast moving" to get your attention (Which he obviously did) as the conflictor was obviously not another C152 or Islander and was likely to "spong" you at short notice.

:ok:

Lon More
4th Jul 2005, 12:02
Whatever happened to professionalism?

There are presently some three threads on these forums where controllers are having a go at each other (I know, I've done it myself in the past)
"My system is better/worse than yours" is not the way forward, particularly as in another thread there are complaints about the travel perks, or rather lack of them, available to control staff

Lon More,
here before Pontius was a Pilot or Mortus a Rigger,and now very happy to be out of it

normally right blank
5th Jul 2005, 21:42
Maybe just nowadays say: "Two Canberras" (would get some attention!). Many years ago RAF "fast movers" would only say (ex.): Twin engine jet.

Lon More
5th Jul 2005, 23:43
Back in the old days:
Twin jet = Canberra or Dominie (c/s gave a clue)
Single jet = Lightning
Twin prop = Viking
multi-engine = Belfast (low level) or Brittannia (above FL 60)

Cuddles
6th Jul 2005, 16:56
I thowt a lightning had 2 engines

spekesoftly
6th Jul 2005, 19:01
Yes the Lightning has two engines, and was sometimes referred to as a 'Vertical Twin Jet', due to its fairly unique engine configuration. Definitely "fast moving traffic", though, sadly, unlikely to be seen flying other than in South African skies. ;)

normally right blank
6th Jul 2005, 22:02
Twin= Also Phantom, Buccaneer, Jaguar, Tornado.
(I'm getting old ;))

DFC
6th Jul 2005, 22:04
Is there a definitive speed for the reactions required to avoid something moving fast? :D

I always believed the description fast moving was used to imply that if it is heading for you then you better be fast moving out of the way. If it isn't yet heading towards you if soon could be could be.

:)

Regards

DFC

Lon More
6th Jul 2005, 22:46
Twin= Also Phantom, Buccaneer, Jaguar, Tornado
New fangled things; they'll be inventing a replacement for fabric covered wings one day.:rolleyes:

Pierre Argh
7th Jul 2005, 22:11
vertical twin jet... military eight jet... I just love it when people thing they are hiding something from you... what else could we have? Double rotary, Supersonic passenger carrier (anyone?)

... and also apologise to all those impoverished ATCOs out there whose employers can't/won't afford 21st century equipment... to think we thought ours was the worst and we were lagging behind on the technology stakes. You'll be telling me you still use chinagraphs next!!!!

Sorry I digress

Spitoon
8th Jul 2005, 06:13
I only use a chinagraph for marking the advisory heights for SRAs on the face of the radar tube these days. I have these hi-tech strip things for keeping track of callsigns and stuff.

Thank heaven for progress.

Vasa
8th Jul 2005, 17:39
Definition of fast-moving:

Any controller given an early go by A watch.

Jump Complete
12th Jul 2005, 13:14
Thank you for the replies. Just a couple of points. The controller did not know they were Canberra's-I identiefied them to him and I subsequently heard him advise another light aircraft of 'a pair of Canberra's'
Canberra's are definatley faster than Islanders but I suppose slow in conparision to other jet traffic!
I understand there are some in use at Marham (target type stuff?) which is fairly close to where I fly but it is the first time I've spotted any in the air so I guess they're not flown very often!

Flobadob
12th Jul 2005, 14:49
The PR9 canberra could outrun and outclimb our GR1 tornados at Marham. Indeed, while controlling Deps at Marham I recall a PR9 that left with a GR1 to join CAS at CLN. The PR9 had to wait outside CAS at FL330 while the tornado caught up!

Now that's what I call 'fast moving'.:cool:

Arkady
12th Jul 2005, 15:10
Chinagraphs! Irreplacable. You'll miss them when you don't have them! We do!!

Dances with Boffins
12th Jul 2005, 15:11
The call is for your information. Best not to alter course at all unless you can see them and they are going to hit you [which is too late anyway]. They will have seen you and can manoeuvre to miss you, as long as you don't make any sudden moves.

"Gibralter Tower, Two 4-jets for the run and break"

"Confirm that is Four 2-jets?"

"Negative" [2 Nimrods arrive at max chat, 200', and peel at the threshold to join the circuit]

ah, the good old days!

eyeinthesky
12th Jul 2005, 15:30
"Definition of fast-moving:

Any controller given an early go by A watch"

Very good! if a little harsh in the brave new world...

;)