Minimum Radar Separation Question
 

I have a quick question which I hope some kind soul can help me with. What is the minimum radar separation between aircraft in the airways and in the TMA in the UK please? I am sure there are many stipulations about this but a rough idea would be greatly appreciated. I tried to look it up whilst in the cruise today but quickly lost the will to live.

Best Regards,
Office Pest.

5 nautical miles

3 nm in the LTMA, for aircraft working TC sectors

And just to muddy the waters further, LHR approach can use 2.5nm, 2nm and also less than 2nm under varying criteria.

I was trying to do the 'rough idea'.

But now, for my edification, do we still use 8NM or 10NM anywhere in the en-route environment in the UK?

10nm still used in SW Approaches and off Hebrides where service is SSR only
NS

Many thanks for all your replies. Yes I thought it was roughly 5nm en-route and 3nm in the terminal area. I fully appreciate it wholly depends on where you are etc....

Best Regards,
O.P.

never heard of 2 and less nm separation,what are criterion for those?:rolleyes:

I'm not going into the criteria because they're in the TC MATS Pt 2 and it's not my place to publish stuff from that here, but suffice to say it involves final approach and parallel runways.

:rolleyes: if you want but the procedures are there in black and white and used as well.

And a SATCO to boot :oh::hmm: :E

Aim for 10, get 2, call it 5. Oh blast, forgot about the SMF.

min sep
 

1/6 of a mile...otherwise known as 1000 feet:E

<<I'm not going into the criteria because they're in the TC MATS Pt 2 and it's not my place to publish stuff from that here, but suffice to say it involves final approach and parallel runways.>>

Roffa.... Yes, but 2nm is not a radar separation surely? Are you talking about visual separation between aircraft on parallel runways? In which case there is no defined separation.

I shall be seeing one of the Heathrow Directors this morning and will be finding out more!! 2.5nm separation on final approach was the minimum when I was there, but that's long ago!

"1/2 a mile behind is better than 3 in front" ... heard from a very old and bold ATCO!

No, I am talking about radar separation HD. It's a procedure that was brought in some time after you left. I can use 2nm separation in IMC conditions under certain specific criteria.

Times they are a-changin'...

Roffa.. Yep, fully understood now. Had it explained to me this morning in words of one syllable!! Just means I take my hat off more often in admiration for what you people do nowadays. I'd never have validated under current conditions.

Bollox.:ok:

Seperation
 

3 miles within 40 miles of the radar head, and dependant on the controllers experience.

Stenner.. Presumably military? I know of no civil procedures in which separation is based on controller experience.

People... please forgive an ancient controller for joining in but I'm still fascinated by ATC and learn a great deal from these forums. Might come in useful when I'm re-incarnated!!

HD

Stenners comment is certainly not derived from UK Military, don't know where he/she is getting it from.

Nothing in the military rules about 'controller experience'. IIRC it states 'where approved, within 40 miles of the radar overhead at or below FL245 between participating aircraft'

Minimum radar separation range of a particular radar source depends on the azimuth error distribution of the radar source. One radar may be good for 3nm at 50 miles, another 3nm at only 40nm (for example). Each radar source (well, NATS one anyway) has a published separation range for 3nm, 5nm and 10nm, where appropriate. I wasn't aware of general figures being used, unless in a unit's MATS Pt2(?).

It also depends if you are separating SSR from SSR, SSR from PSR and (worst case) PSR from PSR.

Then there's MRT........:}

RS

And to quote an ex-colleague, "Traffic is well clear on radar. You will miss him in the turn"

That was before the days that the radar picture was recorded, of course. We wouldn't get away with that now would we? :E

Just been looking at Monday morning's LHR Webtrak as I was quite amazed with the busy sky outside my East London kitchen window while I was masterminding a bank holiday fry-up! Both LHR and LCY were on westerlies.

Having tired of reconciling the LHR inbounds I'd seen decending to 4000 with the (unplotted by Webtrak) LCY outbounds I'd seen launching beneath them I then noticed how the separations really do decline surprisingly sometimes from around that 13nm mark on the ILS.

I found one instance of number 1 with a (spurious?) final readout of 87kts at 308 feet :eek: with number 5 following up at 175 kts already overhead Brixton! And still they kept coming! Actually the "number 4" so to speak was on the parallel 27R with the others on 27L. It wasn't IMC, but evenso it implies Roffa's MATS Pt 2 must surely get well thumbed !

You still here and going on about LHR and LCY?

I'm afraid all it implies is that Webtrak isn't an approved surveillance radar system so believe exactly what it shows you at your peril.

Meantime I'll stick to actually knowing the rules and using the kosher equipment.

p.s. the Pt 2 is mostly distributed on a CD these days.

Oh:8
... Well I hope said cd is distributed with a nice pair of white gloves - otherwise we might imagine the thumb prints might get in the way of the rule when you least expect it :ok::p

Yep still here on high days and holidays at about 16DME :ok::ok:

I've had 1/2 nm at FL350. Both pilots had each other in sight (2 x DC8) and were happy for a visual climbthrough.

Lon More

The chap in question... didn't have the initials G.P. by any chance?

Radar separation? Eezy peezy. Get half an inch between blips on the tube. If things look a bit tight, just drop down a range - bingo! Separation regained. :E:E