Question to EGKK TWR ATCO's

[BTY]

Hi,

My question to you guys who are working in the busiest airport of the world using a single runway in your daily operation is about the procedure used in EGKK regarding the wake turbulence separations between arrivals and departures vs. the displaced threshold.

According ICAO :
A separation of 2 minutes shall be provided between Medium (Upper & Lower), Small or Light aircraft following a Heavy aircraft and between a Light aircraft following a Medium or Small aircraft when operating on a runway with a displaced threshold when:

(a) A departing Medium (Upper & Lower), Small or Light aircraft follows a Heavy arrival or a departing Light aircraft follows a Medium or Small arrival;

(b) an arriving Medium (Upper & Lower), Small or Light aircraft follows a Heavy aircraft departure, or an arriving Light aircraft follows a departing Medium or Small aircraft;

(c) if the projected flight paths are expected to cross.

My question is :confused::confused::confused::
Do you strictly apply this rule, or does your regulator accept exceptions. Example : a B747 landing on 26L followed by a A320 or a citation-jet (LIGHT) departing from the end (M1/3) ?

Thanks for your answers !!!! :ok:

[BOAC]

It is a while (sadly) since I flew at LGW, but I seem to recall that M does not meet the 'displaced threshold' criterion which I think is 300m?

[SilentHandover]

If we believe that the flightpaths will cross we apply the required wake vortex. The bulk of our operations do not require this as the departure will still be rolling at the point where the previous lander touched down.

[vespasia]

The devil is in the detail!

In the ICAO requirements the a), b) and c) layout makes it look like those situations are separate - what it actually means (note the cunning semi-colons after a) and b)) is that if the flight paths are expected to cross in situations a) or b), THEN that wake turbulence separation is applied. It's not often that those conditions exist here at Gatwick (and we can often avoid them tactically e.g. light aircraft use holding point B to reduce the likelihood of such a situation), but if they do, we aplly the separation.

Hope this helps:)

[GAPSTER]

Been a while since I was there and I'm sure you will get a more comprehensive and up to date answer before long but...

best hourly movements circa 10 years ago around 55,think it must be approaching 60 by now...this includes heli traffic but there are not so many of those.Daily rate best was over 850,would like to see the latest on that myself.Achieved by top notch tactical usage of holding points and slot times by ADC,close coordination between ADC and App regarding spacing and extremely accurate spacing by App...occasionally complemented by the ability to use 2 1\2 mile gaps when weather conditions permit.

Gatwick is possibly the best example of how to maximise rwy utilisation at a single rwy field.

I stand to be corrected:ok:

[cossack]

Back in the late 90s before the second runway was built at Manchester, the movement rate was often 55+/hour. Granted this wasn't for as many hours in the day as Gartwick but it was done. The record stood at 57 for a couple of years and then one September morning between 8 and 9am the 60/hour was achieved without any helicopters. ;) 32 departures and 28 arrivals IIRC.

I don't think that record could be broken unless there were a concerted effort to load the place up with low runway occupancy types. Accurate spacing from approach and perfect weather conditions (light head wind) contributed to the achievement. :ok:

Then the second runway arrived and took all the fun out of it.

[QuestionMaster]

Gatwick's daily record is 895 and Hourly record is 60. Both about 2 years ago.

[vespasia]

Busiest hour 60,

busiest day 897 (IIRC the 895 was revised upwards but not 100% sure?)

regularly 55-57 an hour, but all subject to right weather, right combination of traffic etc. The more heavies in the mix, the more difficult it is to achieve:ok:

[haughtney1]

You guys need to go and defend your patch against the ozzies....who some claim that BNE is busier...and they do it better with a single rwy :E

[GAPSTER]

...claiming it down the pub are they? Not many of 'em on here:E

[vespasia]

some claim that BNE is busier...and they do it better with a single rwy

Always dodgy to compare airports with different procedures etc., but Gatwick movements 2010 240,500 (CAA figures). Brisbane 2010 187,956 (Airservices Oz figures).

Don't want to knock anyone here and complexity can make a huge difference, but in numbers using the runway terms BNE has a way to go yet...

[Dan Dare]

...that, and having twice as many runways as Gatwick

[hangten]

The surf's better too... :(

[Dan Dare]

Runway utilisation improvement is one of the nats consultancy streams sending out managers all over the world (to the relief of us workers). So we could tell you, but we will all be sacked for taking work away from our managers.