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jcowburn
6th Jul 2009, 16:39
Dear All,

I often hear pilots referring to the Margo Restriction? What is the restriction at this waypoint?

cheers

Jim

10W
6th Jul 2009, 16:44
Descent to FL260 level by MARGO for TMA arrivals to the Scottish TMA area from the South.

121decimal375
7th Jul 2009, 07:16
Im sure alot of the operators really dislike the MARGO restriction, whenever traffic allows we try to be as flexible as possible.

The MARGO restriction has 2 main objectives.

1. Aircraft ware forced to be within suitable level bands to allow easier sequencing and speed control into the Scottish TMA airfields.

2. At such times when the oceanic track structure is through Scotish airspace then this enables the hight sector (Dean Cross sector 135.525) to get the aircraft below the crossing transatlantic traffic. This increases capacity and reduces controller workload. This also means that when the Dean Cross sector is split, the Scottish TMA inbounds do not penetrate the Dean Cross North sector (135.855)

Hope this helps

salsaboy
7th Jul 2009, 10:24
Doesn't work out too bad for EDI or GLA... means a slightly shallower than 3degree descent to FL70 by TALLA/LANAK but no probs.

Lately I have often been cleared direct to LANAK or TALLA, then handed over to the next scottish controller and then given the MARGO restriction... not a major problem, but causes a bit of extra work reprogramming the FMS. (means putting the coffee down! ho hum)

fisbangwollop
7th Jul 2009, 18:27
The Margo restriction was the number of jars of home made jam she would let you have....enjoy your retirement "Margo":ok:

javelin
8th Jul 2009, 01:01
Glad I didn't start this one :E

bad bear
8th Jul 2009, 08:33
1. Aircraft ware forced to be within suitable level bands to allow easier sequencing and speed control into the Scottish TMA airfields.

er no. it forces the Glasgow inbounds that would otherwise be 4,000' higher than the Edinburgh inbounds in to a conflict that other wise would not have to be resolved while at the same time wasting fuel.

I wish I could see how many planes there are going over the pond that actually need to be so low over MARGO that every plane going in to the TMA has to be thousands of feet below their optimum descent profile (esp if there is a north wind) and burning fuel that the airlines cannot afford, also how busy does a controller have to be that the coordination cannot be done. Redesign the sectors if needs be .

b b

10W
8th Jul 2009, 08:55
Bad Bear,

You clearly don't know the airspace or traffic flows, otherwise you would know that it is not a restriction due to North Atlantic traffic routeing through MARGO.

I'd suggest you visit.

bad bear
8th Jul 2009, 11:46
2. At such times when the oceanic track structure is through Scotish airspace then this enables the hight sector (Dean Cross sector 135.525) to get the aircraft below the crossing transatlantic traffic. This increases capacity and reduces controller workload.

shoot the mesenger!

rolaaand
8th Jul 2009, 15:20
FL260 by MARGO in the prevailing SW wind really isn't that restrictive at all,and it generally gets cancelled during quiet hours which is 2200-0700 and at certain times at the weekend. Even when told no restriction most aircraft types still cross MARGO around and sometimes below FL260 anyway.
I'm sure 10W would probably be able to explain better than me, but almost all of the level restrictions in UK airspace are designed to maximise overall capacity, which is what the airlines want. However if the airlines put pressure on nats so that traffic could always fly at optimum cruise levels and have continuous descent from cruise to touchdown, with the aim of saving fuel,then i'm sure nats as the service provider would be happy to oblige. The downside of this would be a massive drop in capacity due to increased complexity.

10W
8th Jul 2009, 17:32
shoot the mesenger!

The messenger was right though. There are crossing traffic flows, but you'll find no crossing upper air routes at MARGO getting in the way, which is what you inferred.

Most domestic traffic will be ABOVE the North Atlantic traffic coming up with them through MARGO so a restriction to solve that problem would look nothing like the MARGO restriction. It would be more like Max cruising level FL240 for traffic landing in the Scottish TMA, hence removing the confliction you suggest.

I quite often remove the MARGO restriction when I can, and see aircraft crossing MARGO even lower than FL260 when given unrestricted descent. Can't be that bad then can it ? ;)

Rolaand is right. Taking traffic out of a sector which doesn't need to work it, by imposing a level restriction, frees up capacity for those who have a much greater need to use it. Volumes of airspace have a defined capacity, above which some form of regulation is required to ensure that the overall safety of the system can be managed, plus some contingency built in for unusual circumstances. Imagine sitting on the ground with a 2 hour delay to fly up over MARGO and onwards across the Atlantic, just so that some domestic traffic can get their best possible profile. Or be sitting out your delay on the ground as a UK domestic aircraft because some Johnny Foreigner has already been airborne for 3 hours and has filled up a slot through MARGO which lets him be a couple of thousand feet above the current profile.

NATS do work with the operators (note, those who make the decisions, not individual pilots who will have wide and varied views) to see what they want. Where you can't have everything, then a choice has to be made. The current choice is capacity.

I wish I could see how many planes there are going over the pond that actually need to be so low over MARGO that every plane going in to the TMA has to be thousands of feet below their optimum descent profile (esp if there is a north wind) and burning fuel that the airlines cannot afford, also how busy does a controller have to be that the coordination cannot be done. Redesign the sectors if needs be .

Alternatively, redisgn the airline schedules so that 10 aircraft are not trying to use the runway at the exact same time, 10 aircraft are not trying to fly the same route at the exact same time, 10 aircraft don't want the same level at the same place at the same time. You could call it Free Flight !

leedseagle
8th Sep 2015, 09:01
Listening to new scanner where planes change frequency over my house 132.858/133.708 to 135.530 they used to say MARGO now its what sounds like ABEBE

rolaaand
8th Sep 2015, 10:47
leedseagle the new point is ABEVI. Exactly where MARGO was. The level restrictions for ScTMA arrivals have moved slightly to the north to two new points. ASLIB for PF/PK and INPIP for PH.

Dave Clarke Fife
14th Sep 2015, 11:31
The Margo restriction was the number of jars of home made jam she would let you have....enjoy your retirement "Margo":ok:

For those not of a Scottish persuasion or baffled by fishbangwallops possibly critic comment, then here is a bit of historical background info

http://www.pprune.org/atc-issues/493470-margo-lawson-cartwright-r-i-p.html?highlight=margo+waypoint