Heathrow Flow Control Problem

[777fly]

From 2030 UTC on the night of Monday 29th July, the Heathrow departure clearance controller began advising that all DVR departures were to expect indefinite delay. Subsequently all BPK and MID departures also went to indefinite delay. The quoted reason was that Maastrict control were accepting no traffic ex-LHR due to severe weather. Eventually aircraft were able to depart after 1 - 1 1/2 hour delays. Apart from one, admittedly severe, thunderstorm which passed over LHR at 2130 we saw no adverse weather over the whole of Europe.
Can any LATCC ATCO shed some light on the real reason for the chaos? I fail to see how one thunderstorm could have affected all continental departures for over an hour.

[747-436]

Not an LHR ATCO but could it have been the Thunderstorm that later passed over LHR way at about 0030 BST?!?!?

[eyeinthesky]

I was southbound in the UK at about that time and heard traffic being advised that Maastricht were not accepting traffic via KOK. It was rerouted via REDFA.

To answer your question, consider the effect of a thunderstorm (or series of them) sitting in the middle of the narrow airway at KOK. If no-one will fly through it then they will go round it and this may put them in conflict with traffic which would not normally be the case. Multiply that by each aircraft wanting to take a different route around the storm and chaos rapidly ensues. Safety dictates that traffic shoudl be stopped from getting to this chaotic state.

Stopping traffic is not a decision taken lightly, so ' one thunderstorm ' was probably not the situation. Just because you didn't see any weather doesn't mean there wasn't any. As for 'the whole of Europe', how do you know? I certainly picked my way aroundseveral huge buildups between the IOM and NOKIN, which I believe still count as being in Europe.

If you don't like this answer, wait until your next request to avoid weather is refused and see how you like the ride...

[bvcu]

Thunderstorm over LGW at 2130 so we had delays for about 1 and 3/4 hours for DVR dep.

[Phantom99]

Worked from 2200 Monday to 0600 Tuesday local on Clacton/North Sea sector relieving some very tired ATCOs from the afternoon shift.

Maastricht were accepting traffic by the time we came in to work the night shift however we still restricted the outbounds due to extreme weather avoidance for arrivals causing increased workload for us, TC, Maas Delta and Koksy. Even had aicraft avoiding at FL400. Dover outbounds were regularly entering our airspace and at one point they had three or four Luton and Stansted arrivals orbitting due to weather.

At about 2300 we were advised of a severe band of weather stretching from overhead Paris to Dover. Avoidance reduced in severity approx 0300 when problems due to turbulence increased. It was not a boring night shift.

So that was the 'real' reason - as you were informed. MDIs were I think 1/5 for most directions.

[777fly]

Phantom99
Thank you for the insight. I guess the weight of traffic is so high now that one sector blocked by weather affects all the others. It was just highly unusual that all 3 airways east through to south were closed at the same time.
For my departure via BPK at 2245 there was no significant weather after passing BPK apart from one small build up over Ostend and it was a beautiful clear night over all of Holland and Germany. It was hard to see why there had been any restriction on that routing.

[Phantom99]

From a Clacton point of view, the increased workload was caused by the traffic avoiding weather between COA and LOGAN. This traffic was turning right towards REDFA then skirting the buildups before turning back towards the CLN/LOGAN/BPK direction.

They would then be head on to departures via BPK/CLN heading East with no wx problems (like you I guess). Although we regularly manage to cope with head on conflict areas, the unpredictable requests for avoidance means level separation is better than lateral using headings: vertical separation = monitoring Mode C = increase workload - MDIs were used to reduce bunching of departures and minimise the likelihood of a/c from LL, KK, SS, GW etc all arriving at the same time at CLN, requiring headings.

Unfortunately you were penalised for others bad fortune!

[1985]

relieving some very tired ATCOs from the afternoon shift.

Being one of those very tired ATCOs, i can say that the weather was horrible from about 1630 on monday. There was a line of CB's that stretched for miles along the south coast, working its way from the IOW and ended up sitting just north of DVR right in the middle of the CLN westbound sectors. As Phantom99 said the main problem started with MAAS refusing traffic because of the weather and the french not letting weather avoidance traffic enter them for the same reason. This meant DVR outbounds and EBBR inbounds went through CLN the wrong way against all the westbound traffic, which as we all know can be very busy, and monday evening was no exception. From about 2000 when the weather was north of DVR then all the westbounds went north towards REDFA and LOGAN against the eastbound depatures. It was very busy and challenging for everyone involved. Departures were stopped for a time because of the shear number that were planned through CLN and REDFA, a large majority of these were earlier flights that had refiled and were trying to avoid the wx around DVR.

My thanks to everyone involved, it shows how flexible both ATCOs and pilots can be when we need to.

[2.5 miles]

Situation; A few years ago bad weather all over the London TMA, Heathrow easterly operations. All and sundry stating that the weather was showing very heavy in the approach funnel and nobody wanted to fly an approach, therefore zero landing rate. Wind was too strong to consider changing ends (which would have meant departures getting airborne into it). Aircraft in the holds were then asking for EATS!!!!!!! (with zero landing rate and no one prepared to fly an approach, crystal ball required).
If aircraft can't fly the optimum routes (understandably) capacity will be adversely affected.
Monday evening, Heathrow again easterly operations. VIR 340 airborne on CPT departure asked for heading 300degs as soon as airborne. Slow climbing aircraft requesting a heading that would put it straight into confliction with all of the traffic on the final approach on 09L!!!!!!
We will do our very best to accommodate requests to avoid weather, regrettably occasionally the answer has to be no.

[777fly]

Gentlemen of ATC,
Thank you all for the story of that evening from your perspective. It must have been a logistical nightmare for you all.The suspension of LHR departures is completely understandable under those circumstances. From the pilots' point of view, it is always the lack of accurate information about the real situation which causes unnecessary second-guessing and changes of flightplan.
In tribute to UK ATC, I re-entered the UK via REFSO on Friday evening of 2nd August at about 1700UTC. On initial contact, it was immediately apparent that the controller's workload was immense. For a period of at least 5 minutes whilst we were on frequency, he issued instructions and responded continuously, without a second's pause, to a huge number of aircraft. The degree of cool professionalism was outstanding and you all have my utmost respect.
I have flown for far too long, all over the world, but it is always a real 'welcome home' to get back to the best ATC environment of all.

[1985]

777fly

I'd love to claim credit!

Come and visit, the more pilots that do the better from our point of view.

[Phantom99]

In tribute to UK ATC, I re-entered the UK via REFSO on Friday evening of 2nd August at about 1700UTC.

Probably an E watch controller, I'll point your post out to them. Thank you.