UK Heathrow

[Spitoon]

Or maybe that the UK uses different spacings from those specified by ICAO and used in many other States.

[rodan]

That's true, but there are also two different standards for civil ATS units within the uk. Something I've never been quite able to understand. If it's perfectly safe at Heathrow, why is it suddenly unsafe down the road at Farnborough (for example)?

[Spitoon]

True rodan, and I've got no answer for that. IIRC LL had approval to do 'land after the departing' and different 'land after' procedures, which were landing clearances when no other airport (perhaps with the exceptions of CC and KK) was permitted to do this. I don't know what the situation is now but the 'big NATS airports' were undoubtedly treated differently by the CAA when the CAA and NATS were a single organisation. What the justifications were I have no idea, no one would say when I asked.

[Eggs Petition]

The UK uses Small as a wake category. Although some others may do likewise (Switzerland) it is unusual.

The UK spacings are
H-H,M,S,L
M-M/S, L
S- S,L

H-4,5,6,8NM
M-3,4,6
S-3,4

To all UK ATCOs, I believe these spacings are different from ICAO and the rest of Europe.

As for cleared to land when one aircraft is still to vacate... well, it does include a certain distance that not many regional aerodromes in the UK could accommodate. I'm out of touch but I think it says the preceeding aircraft must be 2500m further along the runway and in continuous motion? However, remember that this is used elsewhere in Europe... as is the 2.5NM on final approach within the last 10 miles.

[Spitoon]

As for cleared to land when one aircraft is still to vacate... well, it does include a certain distance that not many regional aerodromes in the UK could accommodate. I'm out of touch but I think it says the preceeding aircraft must be 2500m further along the runway and in continuous motion? However, remember that this is used elsewhere in Europe... as is the 2.5NM on final approach within the last 10 miles.

Again, true, but the cleared to land with one to vacate (reduced runway separation) has only recently been formalised and incorporated into ICAO documents. LL was doing it long ago. And not every airport is handling aircraft the size of those at LL, so the distances involved might be accommodated on the runway length available. But the principle was that LL was in some way able to use these procedures - and again I think CC was similarly authorised - whilst other airports were not.

BTW, on the wake vortex categories (or wake turbulence as we're now supposed to call it on the RTF), I think that even for the categories that are used by ICAO the weights used as the cut-off point in the UK are different.

[Lon More]

Is this "substandard" Heathrow the one refereed to in other threads as the best airfield in the world with the best Air Traffic Control?

[Geffen]

After the landing/departing cleared to land has sadly been removed from the ATCO tool box at Heathrow. At least no one can get confused by it anymore.

[Gonzo]

But the principle was that LL was in some way able to use these procedures - and again I think CC was similarly authorised - whilst other airports were not.

I would imagine that given enough time we could find procedures that other airports can use, but others can not.

Anyway, isn't the difference in vortex spacing down to the increased density of the air mix due to pollution?

[Spitoon]

I would imagine that given enough time we could find procedures that other airports can use, but others can not.

Gonzo, I am sure you are right. But I wasn't seeking to be critical of LL, simply trying to illustrate that (and I think it's down to the CAA) treated different airports in different ways for no apparent justifiable reason. If after the landing/departing cleared to land was safe for use at LL why shouldn't it be used at other airports given suitable infrastructure? But it wasn't an option for other airports. As Geffen alludes, it caused confusion - I remember one conversation with a LL-based pilot I had at my place of work when he wanted to know why, in the same circumstances, at 'home' he got cleared to land and we said "land after". Maybe not surprisingly I couldn't give him a satisfactory answer!

[Gonzo]

I agree Spitoon, and on the 'land after/after the landing, cleared to land' matter I very rarely used them, purely because most crews would not understand the differences.