Longitudinal Separation under radar control?
 

Hi,
could please anyone clarify me the required longitudinal separation between aircrafts in cruise flying the same track when under radar control?
(A reference will be greatly appreciated)
Thanks.

5nm enroute, 3nm approach

Doc 4444, implemented in whatever countries local documents. MATS in the case of Australia

For the UK, have a look here:

http://www.caa.co.uk/docs/33/CAP493Part1cor.pdf

CAP 493 - Manual Of Air Traffic Services (MATS), Part 1.

Section 1 (Air Traffic Services)
Chapter 3 (Separation Standards)

It doesn't give much away as it would ultimately be laid down in the controlling unit's MATS Part 2, or in the case of the Military. Military Manual of Air Traffic Management (MMATM).

AFAIR its 5nm in most places and some areas its increased to 10nm because of radar coverage.

I hope that helps.

MM

It's not set down as a longitudinal (or anything else) separation when using radar - aircraft are just kept apart by a minimum distance. The standard is 5 NM but in areas of poor radar cover or if the aircraft is a long way from the radar head the distance might be increased, sometimes the increase might be in the lateral plane only because the positional accuracy of the return is reduced in such circumstances - for the old timers amongst us this is saying much the same as 'the blips get huge!'

There are lots of separation standards used around the world depending on equipment and circumstances. We use 3, 5, 8 and 16nm in our airspace, depending on which radars we are using and what mode of radar display is being used. But you'd be a brave/stupid controller to use 5nm behind an A380 or B757 in the cruise; never forget wake turbulence separation. You'll get complaints from some pilots even when you are applying the required minimum separation if they feel the bumps.

Okay that was VATSIM, but it is based off AIM Chapter 3 Section 2 (Controlled Airspace) and the FAA Order JO 7110.65U

Regardless of the required separation, spacing in the cruise will also be governed by intra and inter-unit agreements. Even if, say, 5nm can be used within a unit, you will usually find a larger in-trail spacing is required between units (or sectors within a unit). This can be 10nm, 20nm, 30nm etc. (or anything) and is the usual determinant when setting up longitudinal spacing in the cruise.

That´s great guys, thanks to all of you for the answers and references.:ok: