Drone disrupting flights from LGW this morning

Interesting. I’m sure I saw or read somewhere that ATC we’re reluctant to get rid of those little handwritten plastic slider things as they were more reliable & easier to glance at.
 
Interesting. I’m sure I saw or read somewhere that ATC we’re reluctant to get rid of those little handwritten plastic slider things as they were more reliable & easier to glance at.
LOL! Towers used to use PFS (Paper Flight Strips) but they have long been consigned to the dustbin of history and the ATCOs love the EFS (Electronic Flight Strips). I was the ATC project manager for implementing them in Dubai International and Dubai World Central.
Control centres have been a little slower on the uptake, basically because of the systems in use. However most have moved across from the dark side, most recently the terminal control centre (handles the approaches for all London airports) at Swanwick.
 
Depends on how you mean by 'monitored'. Radar is very limited in range and is only used to control aircraft within UK airspace (the Oceanic boundary is 10 degrees West in Scotland, 15 degrees further South). In yea olde days it was a completely procedural service with 60NM gaps between aircraft in trail on the same route/height/speed and separated by 10 degrees of latitude. If you imagine the routes crossing the Atlantic they go something like 57North 10West, 57North 20West, 57North 30West, 57North 40West, 58North, 50West. The aircraft are reporting the crossing point times on HF radio (to Ballygireen in Ireland) who pass it to the Oceanic Control Centre at Prestwick. Prestwick Control hand the traffic over to the Canadians about halfway across.
More info in the link
Since the introduction of satellite technology and the ability to 'see' the aircraft (a visual representation in real time) the separation standard has reduced to 30NM in trail. This is good for the airlines as they can now get more aircraft on the preferred route as opposed to one with less optimal winds.

When I first arrived at Prestwick centre in 1983 the Oceanic part was a bit rough & ready. The way they worked out the NAT tracks (North Atlantic Tracks, the route structure) was by receiving the plans from the airlines and putting a tick by the route 50N 15W, 51N 15W, 52N 15W, 53N 10W, 54N 10W, 55N 10W up to 61N 10W. The more ticks then that was the NAT track and they'd send out the NOTAM telling everyone twice a day. When I went back to Prestwick to help get the shiny new centre operational (which took 3 years) in 2005 Oceanic was plonked right in the middle of the Ops room with lots of lovely new kit, very nice. I was curious about what they were using to plan the NAT tracks and amused to find they were still using the trusty old chinagraph pencils LOL!
The NAT OTS now has RLatSM too.

Translation: The North Atlantic Organised Track System (see above) now has reduced lateral separation minima. It used to be 1 degree of latitude (60nm), it’s now 1/2 a degree.

The OTS changes twice daily, the morning (U.K. time) is largely dedicated to eastbound, the night time to westbound which suits the prevailing traffic flow. The tracks change largely based on prevailing wind which is usually westerly so the morning tracks try to stay out of the (head)wind and the night time ones try to stay in the (tail)wind. Airline flight planning systems mainly work on MTT, minimum time track so everyone tries to use the wind to best advantage. The choice of track by the planners as described above is a) news to me, thanks for that and b) fits the description.

The OTS is largely used for US/ Canada destinations and look curved because they are Great Circle routes (the shortest distance between two points on the surface of a sphere is along a Great Circle). The curve is down to the way the map is drawn. Destinations in the Caribbean and south usually use a Random Track ie not on the OTS as it’s shorter. Because of the Great Circle thingy, you’re most likely to go on a more northerly track the further east your destination is. It looks all wrong, apparently going north to get to LA but it’s a trick of the eye. Typically if we go to say Cancun on the Atlantic coast of Mexico, we coast in over Newfoundland, if it’s Puerto Vallarta on the Pacific coast of Mexico we’d coast in over Labrador, much further north. If you’re interested, we coast in about 1/3rd of the way there to Mexico and about 1/4 of the way to PVR. The Atlantic crossing is small beer really.
 
The choice of track by the planners as described above is a) news to me, thanks for that and b) fits the description.
I was more than a little surprised to still see it in use! It dates back to when airlines started using those routes (before ETOPS). Prestwick was the en route destination in UK for all the American aircraft coming over during WW2 and after as it was one of the few licensed international airports. Now pretty much everywhere is and Prestwick is dying.
I always thought of the NAT track system as flying an elongated S shape Not sure how flat earthers view it, straight lines I suppose
 
D3C0C259-1794-4BCD-BBBF-E72F8C4BC4C8.jpeg

Here’s the OTS tracks in red for eastbounds tonight with a Cancun-Manchester flight following the black line from bottom left, following the southernmost OTS for a bit then diving off and crossing a few. It can do this because it’s a 787 and flies above the OTS.

Tracks S, T and U are reduced lateral separation and require higher grade nav and autopilot kit.

If you’re really up to impress that bird with the big tits in the pub, eastbound tracks start with Z in the south and go up the alphabet however many, westbound tracks start with A in the north and go down however many. There is no fixed number of tracks but about 8 is usual.

The green lines are the OCA, Oceanic Control Area boundaries, clockwise from bottom left it’s Nu Yoik (New York to everyone who’s not a Nu Yoik ATC bod), Gander (Canada), Shanwick (a hybrid of Shannon where the radio operators are and Prestwick where the controllers are) and Santa Maria in the Azores.
 
View attachment 371902
The green lines are the OCA, Oceanic Control Area boundaries, clockwise from bottom left it’s Nu Yoik (New York to everyone who’s not a Nu Yoik ATC bod), Gander (Canada), Shanwick (a hybrid of Shannon where the radio operators are and Prestwick where the controllers are) and Santa Maria in the Azores.
Something else of possible interest is that Shanwick (Prestwick) and Gander (Canada) use the same systems. Not certain if it got implemented but it was intended for them to 'share' the whole of the pond. One night Shanwick and the next night Gander. Saving on manpower.

When the system was introduced I was (mainly) working at Swanwick. We did software upgrades at night by making the simulator a live OPS room and moving the operation into there while we switched over and tested. We had to get back into the main OPS room by 5.30 ready for the morning rush. But also for all the oceanic traffic which hits UK early o'clock going onto Europe etc. It concentrated the mind to see quite literally dozens of aircraft heading to UK and knowing that there was NO contingency if we reduced the flow rates because the OPS room wasn't back. These planes were coming no if's but's or maybe's!
 
Toastie you might want to explain to the audience about ETOPS and how you can fly so far from an airport when crossing the pond :)
 
@Toastie is the screenshot of OTS tracks from something open resource / web-based or, is it company software?
 
Here goes!

ETOPs is Extended range Twin engine Operations, it used to be EROPs and is sometimes called Engines Turn Or Passengers Swim. It came about with the advent of efficient twins like the 757 and 767 which started easing out the DC10 and Tristar (3 engines) and the 747 (4) for the simple reason they burn less fuel.

The manufacturer has to prove high levels of reliability in all sorts of systems, not just engines, things like hydraulics, electrics and believe it or not, shitters. There has to be some serious redundancy too. The operator has to prove their training and procedures are up to speed and away we go.

The system splits into 3 bits of time really. Firstly get your approvals as above. Next, on the day do a load of theoretical planning which has to tick all sorts of boxes and is valid up until the point the aeroplane moves under its own power, ie starts to taxi, the so called “despatch” point and after that, it all switches to real time and the third bit which is en route contingency planning and monitoring. The aircraft also needs to have an enhanced pre flight check done by the spanner wielding fraternity.

The approval will be specific to the type and operator. The vast majority are “180 minutes ETOPs”. On the day, minor faults can reduce that so say you have a nav system out, you’re approval will state that that reduces you to say “138 minutes ETOPs”. Hold that thought.

All twin aircraft must stay within 60 minutes still air (ignore the effect of wind) flying time of a useable airport at a speed which is designated as the single engine flying speed in the approval unless they are ETOPs certified and all the above is done. For the 787 this means stay within 400nm of a suitable airport. Suitable means ATC, long enough runway, nav aids, fire cover etc. Note, weather or indeed the serviceability of any of that kit isn’t considered. Yet.

6F17F685-9B01-4E14-8F9E-AC7198D2A2D6.jpeg


Look at the map above,you’ll see some circles with eg “400 TXKF”. That means 400 nm from Bermuda (CYYT is St Johns, Canada, EINN is Shannon and LPLA is Lajes in the Azores. Go outside those circles and you’re ETOPs and must play the game.

Next up, on the day, you must stay within 180 minutes flying time at the designated single engine flying speed of a suitable en route alternate (ERA). For the 787 the speed is 400 kts, 3 hrs (180 mins)= 1200nm in still air. This time though we need to make sure @exbluejob and his mates aren’t out on the piss, nobody’s dug a hole in the runway, the firemen aren’t on this piss with the ATCers and there are no tropical revolving snow storms forecast. There are stricter than normal limits on the weather based on what nav aids are available.

On the map above, the planners have selected the airports stated. In reality there will be dozens down the eastern seaboard that fit the bill but the next bit dictates which ones get chosen. We can now go flying and from here on in I can do what the feck I want and the weather limits etc I use are less restrictive than in the above planning phase.

On the above map you’ll see some lightning type arrows with some data on them. Look at the bottom left one which says “CYYT 604nm Heading 027” and “TXKF 461nm Heading 213”. These are called Equal Time Points (ETPs) and they do what they say on the tin. At that point it will take me the same TIME to fly onwards to St. John’s (CYYT) as it will to fly back to Bermuda (TXKF). The distances are different because now we are going to consider the effect of wind (this tells me there’s a tailwind going north, we will be going faster so will cover more ground in the same time).

You must have enough fuel at each of these ETPs to either go on or go back. It’s for that reason that you pick carefully because you don’t want to be carrying more fuel than necessary. If you think about it, generally the last one is the problem one but not always. Going to Barbados we normally have to load extra because there’s a lot of nothing round that part of the world. The fuel is planned on a range of scenarios like a Decompression on one engine and takes the worst case.

En route we monitor fuel burn and systems etc and can bin the plan if we need to. I recently had to divert off exactly this routing because someone was taken seriously ill but I didn’t go to St. John’s, I went to JFK as there’s better medical care, it was nearer and I wanted it in my log book.

That’s it. Simples!

Back in the day we did all this manually, computers do it all now and we just give it a sense check, launch, drink tea and discuss who’s going to do what to whom amongst those on either side of the flight deck door should the extremely unlikely opportunity arise (at which point most of us would run a mile).
 
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Toastie you might want to explain to the audience about ETOPS and how you can fly so far from an airport when crossing the pond :)
Engines Turn Or Pax Swim Pretty much covers it


Edit bugger beaten to the punch by @Toastie

I remember when 90 mins was an ambition ( Im in the Id rather have 4 doncs if im mid Atlantic camp - on each wing for preference )
 

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