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starliner
30th Jul 2012, 05:55
Aircraft from the Ockham stack generally peel off and approach the field from the south. Occasionally though, esecially during the 6am rush, they peel off and fly north over the field and join the approach from the north, fitting in between LAM and BOV arrivals. Interested to hear if there is a "rule" as to when this is done, or is it based on the landing runway.
Tks

Talkdownman
30th Jul 2012, 07:27
This is totally at the discretion of the Heathrow Number 1 Director (The Master Director if it is 'split' No.1 N and No. 1 South). The vectoring to the landing runway includes both right and left-hand circuits and if spare capacity is identified in the opposite circuit then an aircraft may, subject to mutual agreement, be taken 'over the top'. It is often an option if there are 'too many off the stack'. The only constraint is that the aircraft must remain within the joint radar vectoring area. The Number 2 (Final) Director isn't bothered which side they appear from as long as they are sensibly spaced for the base turn. Certain ATCOs favour its use more than others when under pressure. Colloquially known as 'Over the top' meaning over the top of the Final Approach sequence hence the initial descent from minimum stack level to (say) only 5000'. It happens occasionally off BNN too then they are taken left-hand. The Radar Directors are mentally 'counting' the track distance all the time for 'Continuous Descent Approaches' and the 'Over the Top' is yet another path-stretching 'tool in the bag' along with 'orbits' and 'once more around the hold'. It can also happen on easterlies as well but much more rarely as there is greater room to maneuver in the first place.

twentypoint4
30th Jul 2012, 10:34
Sometimes to reduce airbourne delays they choose the odd inbound aircraft to land on the departure runway. Aircraft are chosen tactically depending on the landing order, wake turbulence catagories and which terminal they are parking at. (Seach for Threads on "Heathrow TEAM")
Say a 747 is approaching from one of the south stacks for 27L and the following aircraft, an A320 also from the south stacks is for 27R. Intermediate Wake Turbulence rules dictate that you must either remain at least 5 miles behind or 1000ft above, but the controllers want to end up with the A320 2 miles(?) diagonally behind the 747 once they're both established on their respective final approaches. By planning ahead and placing the A320 on the other side, it saves Heathrow Final Director quite a bit of work and makes it much easier to put the A320 2 miles diagonally from the 747 infront.
This is one reason for it! I hope the explanation makes sense.

DaveReidUK
30th Jul 2012, 12:02
Sometimes to reduce airbourne delays they choose the odd inbound aircraft to land on the departure runway. Aircraft are chosen tactically depending on the landing order, wake turbulence catagories and which terminal they are parking at.

A trial is currently in progress (continuing up to the end of March 2013) which includes provision for landing up to 12 aircraft per hour on the departure runway, subject to defined delay triggers.

HEATHROW DIRECTOR
30th Jul 2012, 19:24
??? What happened to TEAM? The procedure for running over the top has been in use for many, many years. Its' so much easier for the Final Director. I used to do it all the time during the 06-0700 hour.

DaveReidUK
30th Jul 2012, 20:02
What happened to TEAM?

TEAM is alive and well and still in operation pretty well every day. But the flavour of the month (well the 9 months from July to March, in fact) is the new, enhanced version, officially designated TEAM*.

Like TEAM, but subject to less stringent delay triggers, and can be deployed at any time from 0700 until the last arrival.

Talkdownman
30th Jul 2012, 20:03
Well, I wasn't gonna mention any names, like you, me...and PL...
I thought it was a great wheeze...but 'D' Watch didn't seem to take to it...

FlightPathOBN
30th Jul 2012, 20:05
Departures and arrivals from the same runway end, without real time wake turbulence measurement, is lemming talk... :=
especially with marine and inversion layers present...

HEATHROW DIRECTOR
30th Jul 2012, 20:28
Any chance of that in English please?

DaveReidUK
30th Jul 2012, 21:07
Departures and arrivals from the same runway end, without real time wake turbulence measurement, is lemming talk

On the other hand, simultaneous departures and arrivals from opposite runway ends aren't such a good idea. :)

vectorer
31st Jul 2012, 09:50
D Watch didn't do it? Yes we did, you just wasn't around when we did!