Takeoff delay behind a 757 at EGLL

[dick badcock]

Been a while since I was there. Do the controllers at EGLL allow for two minutes for a meduim aircraft to take off behind a 757? If not, why not?

[120.4]

I can't speak for the departures, being an approach man (although I don't believe they do unless it is specifically asked for).

On approach we still treat the B757 as an upper medium (specific to the UK) meaning that B737s and similar get 4 miles. There are an increasing number of airlines however which now insist on Heavy spacing (5 miles).

Thus far the argument has been that no proven case has been made to change; the reality is that commercial pressure is now backed up against inadequate runway capacity.

Point 4

:)

[1261]

The UK does not apply any departure separation for another "medium" (or "small") aircraft following a 757. The pilot can, of course, request increased separtation for any reason she/he likes. This is frequently the case at EDI for CRJs following 757s!

I remember hearing somewhere (and therefore cannot vouch for this) that the reason for this is historical; when the 757 first came to the UK in the mid-eighties, most were registered with a lower MTOW (99 tonnes?) for tax reasons (I believe), hence well within the UK "medium" vortex category. Elsewhere in the world, 757s are had a much higher MTOW (138 tonnes?) and were treated as heavies.

This would also explain why in the UK the 757 is thought of as a "high performance" aeroplane, and as a pig elsewhere in the world :)

[Mr Fishy]

A couple of years ago at Man I took off behind a 757 with very little separation and encountered pretty bad wake vortex (a report was filed), I was flying an A320 . So now I always request two mins. Correct me if I am wrong but I believe in the states that ATC treat the 757 as a heavy. I believe the FAA concluded that the vortex from the wing was significantly higher than from other aircraft of that weight.( < 136t)

[AKI]

I don't know how things are in the states. But in Denmark the 757 is to be considered Heavy. So that means that other mediums get 5 miles spacing on the finale, and 2 minuttes delay in depature.. But because it aint Heavy according to the normale ICAO standards a 757 is considered medium when its behind another heavy......
Take care

[ATCO Two]

As has been stated, the B757 in the UK is classed as an upper medium, therefore departure separation for a lower medium or small behind a B757 is one minute, (i.e. "wheels up") on diverging routes. Pilots are entitled to ask for extra separation, but please inform the Controller BEFORE you line up - s/he may change the order to improve expedition, or s/he may be relying on you rolling promptly with landing traffic on final.

[chiglet]

"Cossack" had a very good thread on this a short time ago
we aim to please, it keeps the cleaners happy

[Scott Voigt]

Most B757's in the states are not heavy... However there are some models now that have a fuel mod that are indeed heavies.

regards

[MrWalker]

In OZ a 757 is a Heavy if it is the preceeding acft and a Medium if it is the following acft. So here you would have got 2 or 3 minutes depending on the intersections used.

[DB_TWR]

757 is considered as an heavy in sweden allso.

[VORTIME]

Sorry to intrude as this thread doesn't appear to concern light aircraft. I regularly fly C150's out of a busy international airport. On occasion, we're forced the share the same runway as the "heavy metal". What do others feel is an acceptable minimum for the operation of a light aircraft following the take-off of a jet?

Tx
ETA

[ATCO Two]

Two minutes vortex separation - more if YOU consider it necessary. But please tell the controller before line up if this is the case.

[information_alpha]

i was taught to that make sure you have two minutes to get a medium/small off behind a 757 as we have all been caught out by pushing a gap for a minute departure and when the plane lines up the captain requests the full 120 secs.

In practice ( if there is nothing on final), after one minute, we tend to say WHEN READY clear take off, in my experience about 70% will go after a minute, about 25% after 2 minutes and some take more - i have seen 4 minutes.

The main thing is that all we have to give you in GB is 1 minute - if you want more - tell us BEFORE YOU LINE UP - we will be very happy to give you more time.

Just a point, we time our 120 secs so that the planes rotate 120 secs apart - if a pilot is timing it (ie has asked atc for 2 minutes - we say roger report rolling) it always seems to be about 3 mins, it seems that they count 120 secs from when the previous departure has rotated THEN the second arcraft starts to roll. I have had a pilot tell me that he had not had the full 120secs - he had but i think he was timing it this way. - Any comments??? (the first a/c wasn't a 757!)

[Gonzo]

I've had someone lined up and on being cleared for take off requested 'another 30 minutes'. :eek:

Rashly assumed he meant seconds!

Gonzo.

[sky9]

I sometimes wonder whether we make rules for our own protection rather than the protection of the departing aircraft.
On a calm day with little wind at low levels 2 minutes might not be adequate. At other times with a brisk wind once the contrail and rotor has broken up it would be safe for any aircraft - or am I missing something?

[professor yaffle]

Vortime

2 minutes if departing from same position, 3 minutes if light goes from an intersection and previous was from full length.
If you are doing a touch and go there should be 3 mins between you and previous departure as you are then considered an intersection departure. (Sometimes you may be instructed to do a stop-go if 3 minutes cannot be applied)
Hope this is useful for the lighties!!

[FWA NATCA]

Dick,

In the US, a 757 is treated just like a Heavy because of the wake turbelence created behind it. This means that non-heavy departures (acft gross weight below 250,000 lbs) behind a 757 will wait 2 or 3 minutes depending on the departure point.

Mike

[skippyscage]

I seem to remember the B757 was upgraded to a "Heavy" in the USA, after an incident when Westwind rolled onto it's back and crashed, on approach behind a B757

[West Coast]

FWA NATCA
I believe the cutoff is 255K vs 250K.