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View Full Version : Two minutes behind a 757 please!!


Secret Squirrel
7th Feb 2003, 01:45
I'm a skipper on the diminishing RJ100 fleet at LGW (formerly CityFlyer) and I have to relate this story to you as it really disappoints me that someone at LGW TWR could act in such a way. I have a very high regard for all controllers and the LGW ones I normally have a special regard for as I have had the pleasure of working with them for the majority of my career. I suspect that it's just the one controller but I'm not sure as the two incidents took place a fair time apart. Here goes:

I'm sitting at A2 and a 757 has just lined up from A3 on 26L. The controller asks me if I'll accept an imediate departure behind a 757 which I respectfully decline. He then has me sitting at the holding point for 15-20 minutes before he allows me to go. In view of the fact that I have been flying out of LGW for six years I am well, aware and used to, being slotted in between two arriving aircraft five miles or so apart. On this ocasion he did not do so, choosing intead to "punish" me for NOT being bloody stupid.

About three months later exactly the same happened, only this time the 757 lined up at M1 and there was a BA 737 at A3. Again I respectfully declined his invitation. I expected him to ask the 737 the same question but he did not. WHY?? Why, also, did he then proceed to punish me again and keep me there for 15 minutes again, allowing the 737 and the whole queue on A3 to line up ahead of me?

Now please don't respond with theories about slots and gaps because, believe me, I should know how it works by now and I do, so you can take it from me that he could have got me off easily on both ocasions without any disruption to his sequencing.

Now look, I know this subject comes up every so often and you're all bored to tears with it which is why I'm not after a legal ANO quote on vortex separation and classification of the 757; I know what the book says but I have run out of control input in roll taking off after a 737 and I can tell you it's not a pleasant experience so I shudder to think what it must be like behind a 757.

My old Grandad used to say, "Common sense is the least common of all the senses". The ANO may state that for departure a 757 is to be classified as a medium, and heavy for approach but the 757 is barely medium (especially the long range ones), and the RJ barely medium; they are each at the upper and lower end of the spectrum respectively. I'm not getting at all the controllers (Unless you all think like this individual, which I doubt) just this particular individual or if it's a LGW thing, then them as a whole.

On a last note I often get lined up behind 757's in AMS, CDG and MAN as well as other places and I always ensure the controller is going to give me 2 minutes. In AMS recently the reply came, "Do I have a choice SpeedbirdXXXX?" I respectfully suggest that if other european countries can acknowledge that a 757 generates wake vortices far in excess of it's weight category we should do the same.

So, LGW, give us a break, please. The RJ's have always played fair; we always make the first RET and we are often airborne by then too.

Rant over, thankyou.

Bright-Ling
7th Feb 2003, 07:12
SS - I don't work at LGW but maybe they were of the belief that as the vortex doesn't start until the 757 nose lifts, they may have given you the option to go straight away believing you will be airborne before the 757 was and above all the vortex wake which is descending.

Also, it may have been offered (not insisted on!) if there was a strong crosswind which would have moved the wake. I understand why you don't accept it, but some probably do which is why you were asked.

Just a thought - and I very much doubt that they would delay you deliberately! If they are like me they just want to get rid of the traffic!!!

B-L

Muppit
7th Feb 2003, 11:28
SS,
Check your PM

:O

Cough
7th Feb 2003, 15:35
Just a bit of food for thought.

The vortex will be affected by the wind on the day. So given a 15 kt headwind, the vortex will drift around 500m down the runway from the point at which the 75 had rotated (in 1 min - back of a fag packet calculation). Not insignificant, and more to the point, probably at the point the RJ will rotate. Add to this the fact a 10 knot crosswind will hold the vortex of the upwind wing over the runway. So a NW/NE/SE/SW wind at around 15kt would not be too good for the RJ boys in this situation.

Second bit of food (must be a nibble) is that it seems to me that the RJ climbs out a lot shallower than the 75 (must be something to do with having too many engines). So say the RJ rotates before any vortex, it will then has to fly through it straight after take off. Bumpy rides for the RJ boys....

SS - I hate it when I get stuffed by the slot situation too. Life...

throw a dyce
9th Feb 2003, 23:23
In the Tower at Hong Kong we were required to give 2 minutes vortex separation for mediums following 757's on departure.It was introduced in their Mats part 1 some time ago.In the Uk it is not required on Departure.However extra spacings is required for mediums following 757's and certain other upper mediums down the ILS.I use that HK departure separation here just in case and certainly would not penalise someone for wanting 120 secs behind one of those things.
Also a friend who flys 744's reckons that the vortex behind a 757 is enough to throw a 744 around down the ILS.I think you're wise to give them a wide berth.

126,7
10th Feb 2003, 16:04
Any ATC with even a vague interest in his/her job should know/care about wake turbulence. But, there are more than I care to mention who dont give a hoot and a few who dont even know what a B757 looks like !!

Muppit
10th Feb 2003, 20:49
The B757 departure problem is well known.....an ATCO 'punishing' a pilot for making a legit request is not on!!:mad:

Secret Squirrel
10th Feb 2003, 22:53
I thankyou all for your replies and messages. Thanx, cough, it's what I was going to to say to bright-ling; nails and heads and all that.

Anyway, I am heartened to read that common sense does prevail amoung the majority of you and that you are aware that it's no joke. Please forgive me if I seemed a little harsh.

I guess I could have written a report on both ocasions but even though the first incident was the more blatant (the feeling of being punished, that is) I was willing to give him the benefit of the doubt. The second time was, perhaps not so clear cut but there was room for doubt nonetheless. In any case, I spent nine years in a boarding school (yes, yes, yes, heard them all, boys!) and so to go writing reports (in spite of the clear advantages in some cases) still seems like snitching and goes against the grain. Having said that, my reason behind this post was, a) to get a feeling for the general consensus on this subject (feedback); and b) to let you all know that we find it dangerous (in.. case... you....didn't..... already...... know....... that).

And so goodnight to you all.

Fred.

Only A Few More Seasons
12th Feb 2003, 00:32
Its not wake - honest - I have had it hundreds of times.

Check out CHIRPS (having said that they were not much help) its all to do with those sodding great engines " trust me I know"

pushapproved
14th Feb 2003, 17:26
Secret Squirrel

There are many permutations and combinations that determine the departure order and it can be difficult to provide the full picture to all the aircraft involved. Our delays are based on push & start request times to airborne. We try to be as fair as possible, at the same time utilising the runway. Some pilots call up to ask 'where they are in the queue' because they feel others are departing unfairly ahead of them, this particularly the case with airlines who only have a short taxi to the hold, which can be frustrating for us when we're busy! (This comment not directed at yourself as you travel mostly from the North Terminal - just a general one!)
All the factors taken into account are inbound/outbound demand, start request times, Aircraft type/performance, SID, Slot etc... Basically we won't necessarily depart you in the order you arrive at the hold. On the other hand we do sometimes get you away earlier than you may expect because your A/C type/SID may be ideal for the situation at the time. All in all you should NEVER be penalised for safety issues. If it happens again make a note of the times involved and call the ATC Watch Manager on your return to Gatwick. We can very easily listen to the RT recordings to try to give you an explanation. Most of us take pride in providing you with the best possible service!!

Happy landings! (& Take Off's!)