Candid76 From United Kingdom, joined Apr 2005, 638 posts, RR: 6 Reply 1, posted (1 year 4 months 2 weeks 3 days 16 hours ago) and read 5198 times:
Here at MAN massive slot delays applying to departing aircraft - around eight hours in most cases where the routes enter the London radar area. One LHR diversion so far, a bmi A319 from Belfast.
Complete choas looms if they don't get this fixed quickly!
Imag From United Kingdom, joined Feb 2007, 106 posts, RR: 0 Reply 3, posted (1 year 4 months 2 weeks 3 days 15 hours ago) and read 5129 times:
Also now advice on BAA heathrow web site that "Passengers are advised that flights departing from Heathrow Airport are currently experiencing some delays due to a problem with Air Traffic Control systems."
TupolevTu154 From United Kingdom, joined Aug 2004, 1684 posts, RR: 39 Reply 5, posted (1 year 4 months 2 weeks 3 days 15 hours ago) and read 5076 times:
Apparently a radar failure and described as the "worst case scenario" by an LGW controller.
Readytotaxi From United Kingdom, joined Dec 2006, 1205 posts, RR: 0 Reply 12, posted (1 year 4 months 2 weeks 3 days 14 hours ago) and read 4603 times:
In the UK we blame it on the "wrong kind of rain/snow/wind/leaves"
Is this a case of the "wrong kind of ATC?"
Do feel for all the people stuck, not knowing when.
you don't get a second chance to make a first impression!
just spoke to some colleagues at work and they say that some easyjet flights have been canx, huge slot delays but flights are leaving and departing but as i said heavily delayed with slots, average slot delay of between 3-8 hours but they are changing all the time
RussianJet From Kazakhstan, joined Jul 2007, 3988 posts, RR: 16 Reply 14, posted (1 year 4 months 2 weeks 3 days 12 hours ago) and read 4352 times:
Quoting Tommy212 (Reply 13): just spoke to some colleagues at work and they say that some easyjet flights have been canx, huge slot delays but flights are leaving and departing but as i said heavily delayed with slots, average slot delay of between 3-8 hours but they are changing all the time
Thanks. How about arrivals? Did we take any diversions?
as far as i know none, ryanair have now canx a few flights now, wots more annoying with the slots are they change soooo fast, 1 min a flight has got a 8hr slot then its changed to 5mins, flights seems to be being held on the ground at destination airports as well, israir showing a 3hr inbound delay so its pretty bad out there, not a gd night to be an ATC controller!
DALCE From Netherlands, joined Feb 2007, 1249 posts, RR: 17 Reply 17, posted (1 year 4 months 2 weeks 3 days 11 hours ago) and read 4102 times:
Just met a friend of mine ( BACF F/O ) and his flights ZRH-LCY-ZRH got cancelled after a 4hr wait in the office up front. Only 1 BA mainline flight to LHR got green light out of ZRH tonight.
I noticed a cxxxd U2 flight to STN aswell.
This must cost serîous money to book hotel rooms for all pax and crews who are stranded elsewhere in Europe.
Who will pay for this?
flown on : F50,F70,CR1,CR2,CR9,E75,143,AR8,733,735,736,73G,738,753,744,319,320,321,AB6. Next flights AMS-CFU-AMS with OR
ORD2PHL From United States of America, joined Oct 2003, 284 posts, RR: 0 Reply 18, posted (1 year 4 months 2 weeks 3 days 4 hours ago) and read 3833 times:
I was a passenger on LH 426 from FRA - PHL today and was impacted by this while enroute. We were told of the error and that we would be holding inside of what appeared to be French airspace until the system was restored, apparently the controllers (based on what the LH flightdeck crew shared) were missing altitude and airspeed data. We held somewhere over the Channel I believe (give me a break I was on my way home from DEL and exhausted!) until after about 20 minutes we were released from our hold and continued.
Don't know what a good source for European flightaware type data would be but DLH426 from 25 Sep should tell the same story above
Mav75 From United States of America, joined Dec 2000, 216 posts, RR: 1 Reply 25, posted (1 year 4 months 2 weeks 2 days 19 hours ago) and read 2737 times:
Hantsflyer27 From United Kingdom, joined Oct 2005, 65 posts, RR: 0 Reply 26, posted (1 year 4 months 2 weeks 2 days 19 hours ago) and read 3007 times:
Swanwick is a small town in south Hampshire where NATS is located, built about 10 years ago or so, but took a long time to come online. About a mile away in Whiteley (my home home town), another small town is the administration side of NATS. Between these two site, i believe most of northern european airspace is controlled/monitered. And yes, when it goes down.....there is all hell to pay.
Cloudyapple From Hong Kong, joined Jul 2005, 1988 posts, RR: 8 Reply 27, posted (1 year 4 months 2 weeks 2 days 19 hours ago) and read 2959 times:
Swanwick is an actual village near Southampton where the London Area Control Centre (LACC) and the London Terminal Control Centres (LTCC) are.
Shanwick however is not an actual place. It's the abbreviation for Shannon and Prestwick, who share responsibility to control the Northeastern quadrant of the Atlantic Ocean. Operations are split between a centre at Shannon Airport and the Scottish Centre at Preswick Airport.
NATS has also a terminal control centre at Manchester Airport, which will be moved to Preswick when the construction of a new centre there completes.
Cloudyapple From Hong Kong, joined Jul 2005, 1988 posts, RR: 8 Reply 28, posted (1 year 4 months 2 weeks 2 days 19 hours ago) and read 2847 times:
Quoting Hantsflyer27 (Reply 26): About a mile away in Whiteley (my home home town), another small town is the administration side of NATS. Between these two site, i believe most of northern european airspace is controlled/monitered. And yes, when it goes down.....there is all hell to pay.
The Corporate & Technical Centre is in Whiteley. It houses a lot of the admin, research and some training facilities. There are also offices elsewhere the UK. Of the major offices, the registered HQ with Company House is Brettenham House on Waterloo Bridge in London. The old control tower at Heathrow has recently been vacated and facilities there moved to Heathrow House along Bath Road. The Training College is still at Hurn near Bournemouth.
Cloudyapple From Hong Kong, joined Jul 2005, 1988 posts, RR: 8 Reply 29, posted (1 year 4 months 2 weeks 2 days 18 hours ago) and read 2755 times:
Quoting ORD2PHL (Reply 18): apparently the controllers (based on what the LH flightdeck crew shared) were missing altitude and airspeed data.
Sounds like an SSR failure there but it's impossible to know which bit of the SSR system failed. There's the primary radar as backup so you see the blips but there's no callsign, FL or speed info on screen.
NicoEDDF From Germany, joined Jan 2008, 815 posts, RR: 0 Reply 30, posted (1 year 4 months 2 weeks 2 days 18 hours ago) and read 2643 times:
Quoting Cloudyapple (Reply 29): Sounds like an SSR failure there but it's impossible to know which bit of the SSR system failed. There's the primary radar as backup so you see the blips but there's no callsign, FL or speed info on screen.
Isn't primary radar also capable of providing Vector, Speed and Altitude?
It can easily calculate speed by comparing runtimes of two echoes, it can easily calculate altitude by measuring the distance (through runtime) and the angle of the incoming echoe and again by comparing the incoming two echoes you can see the vector.
Well, I don't think a PSR can mesure the vertical angle of the echoe. At least here in France they can't. However a complete SSR failure is unlikely since there are plenty of radars. The software or network processing the data from these radars may fail but there are redundancies in both these areas through the SUR (secours ultime radar) which will display squawk code, level (with no indication of tendancy) and ground speed.
Primary radars are only used in terminal areas to reduce the separation minima because of their improved accuracy.
Readytotaxi From United Kingdom, joined Dec 2006, 1205 posts, RR: 0 Reply 33, posted (1 year 4 months 2 weeks 2 days 15 hours ago) and read 1722 times:
Quoting GDB (Reply 15): other parts of the control system had some sort of software fart?
Now what would that sound like?
you don't get a second chance to make a first impression!
NicoEDDF From Germany, joined Jan 2008, 815 posts, RR: 0 Reply 35, posted (1 year 4 months 2 weeks 2 days 12 hours ago) and read 1585 times:
Quoting Icna05e (Reply 31): Well, I don't think a PSR can mesure the vertical angle of the echoe. At least here in France they can't. However a complete SSR failure is unlikely since there are plenty of radars. The software or network processing the data from these radars may fail but there are redundancies in both these areas through the SUR (secours ultime radar) which will display squawk code, level (with no indication of tendancy) and ground speed.
Primary radars are only used in terminal areas to reduce the separation minima because of their improved accuracy.
Hmm I don't know. You can bundle electromagnetic waves, can't you? Anyone insights?
Still, Vector and Velocity are measureable for sure. So you still have a good idea of where airplanes are going how fast.
BlueShamu330s From United Kingdom, joined Sep 2001, 2064 posts, RR: 30 Reply 36, posted (1 year 4 months 2 weeks 2 days 11 hours ago) and read 1534 times:
A datalink failure will leave raw SSR squawks on the screen. Altitude/Flight Level and Groundspeed indications will not be compromised.
However, if it is ever a complete failure of the SSR feed, then ATCOs are left with raw, primary data, i.e. just the historical trace of where the aircraft has been. Unbelievably, there are some places in the world where Primary and Secondary are not co-located; in that situation, if Secondary goes, the screens go blank, game over, and it's back to procedural ATC.
Quoting NicoEDDF (Reply 35): Still, Vector and Velocity are measureable for sure. So you still have a good idea of where airplanes are going how fast.
Using just Primary radar, velocity can only be "guestimated" by the Controller watching the screen. He hasn't the ability, time or information to calculate the speed accurately, and has to rely on experience and the movements of the other Primary traces on the screen to get a picture. He'll have access to upper wind information, but if Secondary goes out without warning, he won't have time to go to the briefing room and have a look at the charts.
The loss of Secondary makes it hard work in a busy environment. Silent handovers between sectors are cancelled, every aircraft in and out of a sector has to be individually co-ordinated, and if the shut down has affected an entire centre, then there will be delays answering the phone as everyone will be trying to do manual co-ordinations. On top of that, without SSR, every single aircraft has to be identified to the receiving sector before transfer, again by phone. Aircraft not identified in that way have to be identified by means of an exact point on the ground, by passing a NavAid, or by observing a turn as requested by the controller. Meanwhile, you're also trying to stop outbounds, so you're calling all adjacent airfields before the message from CFMU gets out. Other sectors quickly get overloaded, and they try offloading traffic onto other sectors, perhaps lower airspace, who are as equally snowed under. Controllers earn their $$$, believe me !
I could go on, but this just begins to illustrate how quickly and how intensively the workload can snowball when a vital piece of ATC kit goes down; imagine the chaos if all the electronic strips disappeared down the tube behind the radarscreen too and it all went blank !!
Well done to all those who maintained service during the down time.
Shamu
So I drive a 4x4. So what?! Tax the a$$ off me for it...oh, you already have... :-(
Icna05e From France, joined Feb 2006, 143 posts, RR: 0 Reply 37, posted (1 year 4 months 2 weeks 2 days 10 hours ago) and read 1458 times:
Well, there sure seems to be differences in the way redundancy equipments are conceived depending on the side of the Channel you're on. I think I like our system better! Then again, in the worst-case scenario we are still left with our strips which happen to still be good old yellow, paper strips.
Quoting BlueShamu330s (Reply 36): Unbelievably, there are some places in the world where Primary and Secondary are not co-located
BlueShamu330s From United Kingdom, joined Sep 2001, 2064 posts, RR: 30 Reply 38, posted (1 year 4 months 2 weeks 2 days 9 hours ago) and read 1437 times:
Quoting Icna05e (Reply 37): Tht would make France a third-world country then?
No, not at all !
I shall phrase it differently and more correctly, as my first attempt didn't clarify whether I was meaning the radar equipment's actual positioning or the availability of both to Controllers.
Primary Radar and Secondary Radar tend to co-exist on ATC systems. Surprisingly though, there are some places in the world where Controllers operate in a Secondary Radar-only environment with no Primary Radar as backup. When their system fails, they have to resort back to basic procedural seperation.
Apologies if you thought my comment was directed at a particular country/company/centre.
[Edited 2008-09-26 15:26:05]
So I drive a 4x4. So what?! Tax the a$$ off me for it...oh, you already have... :-(
Icna05e From France, joined Feb 2006, 143 posts, RR: 0 Reply 39, posted (1 year 4 months 2 weeks 2 days ago) and read 1277 times:
No need to apology BlueShamu330s, there was no offense taken. It's just different ways of seeing it depending on the country you're in. Still just to let you know, we don't have primary as a back-up (not in ACCs at least, it's a different story in approaches), however everything from the radar station up to the screen is doubled and/or has a rescue system. "Secours ultime" is, the data is taken through a different network to different computers where it is basically processed (no correlation between a squawk and an ID) and displayed on the screen.
Anyway, must have been a hell of a night for all controllers involved! Bravo for the work done!
NicoEDDF From Germany, joined Jan 2008, 815 posts, RR: 0 Reply 40, posted (1 year 4 months 2 weeks 1 day 6 hours ago) and read 1070 times:
Quoting BlueShamu330s (Reply 36):
Using just Primary radar, velocity can only be "guestimated" by the Controller watching the screen.
No, I don't buy that.
You can "calculate" the distance by measuring the runtime of a signal and its echo.
You agree to that?
So with two echoes you have the difference in run time (frequency shift due to doppler effect) with which you can accurately determine which speed the object is going in reference to the line of sight from radar to the object.
Together with the horizontal azimut of two pulses you get exact vectors, speed, direction and distances (pulse-doppler).
So, while I am not sure about the vertical azimut to determin the altitude, I am quite sure that direction, distance, speed and vector (as combination of the former) are no problem whatsoever for primary radar.
But I agree, the loss of secondary in a busy environment is not by any means helpful.
Well, this is supposing you have a processor saying "ok, those 2 echoes belong to the same aircraft". However the thing is, Murphy's law dictates thas this processor was part of the system that just broke. So you are left with the raw data (horizontal azimuth and distance).
I don't want to bother you again with our "secours ultime" but well... it does a really basic linkage to provide groundspeed, and that's made easier because it gets its data from SSRs. So I assume it is made through mode A codes. Now, with PSR data I don't see how you link 2 blips to the same aircraft.
BlueShamu330s From United Kingdom, joined Sep 2001, 2064 posts, RR: 30 Reply 42, posted (1 year 4 months 2 weeks 10 hours ago) and read 865 times:
Quoting Icna05e (Reply 41): Well, this is supposing you have a processor saying "ok, those 2 echoes belong to the same aircraft". However the thing is, Murphy's law dictates thas this processor was part of the system that just broke. So you are left with the raw data (horizontal azimuth and distance).
I don't want to bother you again with our "secours ultime" but well... it does a really basic linkage to provide groundspeed, and that's made easier because it gets its data from SSRs. So I assume it is made through mode A codes. Now, with PSR data I don't see how you link 2 blips to the same aircraft.
Agreed. You can't, because you can't protect from pop-ups, echoes, dense flocks of birds, high-sided vehicles going over raised bridges, intense weather etc. There is no built-in intelligence to a Primary Radar. It simply paints on the screen whatever is reflected. It can't assymilate what has caused the echo trace and it can't associate two returns as belonging to the same reflective surface, hence Nico, for an ATC application there is no fail-safe way of achieving your argument/theory.
So whilst technically, you could calculate the velocity of a moving object purely from Primary returns, from a safety risk assessment point of view, you would have to limit each sector to one aircraft at a time, and on that basis, departure lounges are going to get full very quickly!
Shamu
So I drive a 4x4. So what?! Tax the a$$ off me for it...oh, you already have... :-(
Cloudyapple From Hong Kong, joined Jul 2005, 1988 posts, RR: 8 Reply 43, posted (1 year 4 months 2 weeks 2 hours ago) and read 742 times:
Quoting NicoEDDF (Reply 40): You can "calculate" the distance by measuring the runtime of a signal and its echo.
You agree to that?
No you can't because:
Quoting NicoEDDF (Reply 40): So with two echoes you have the difference in run time (frequency shift due to doppler effect) with which you can accurately determine which speed the object is going in reference to the line of sight from radar to the object.
Together with the horizontal azimut of two pulses you get exact vectors, speed, direction and distances (pulse-doppler).
You do not get a dot return, you get one big blob the size of which depends on the range. Some systems display everything that has been echoed back as a big blob while others do some primary interpolation and displays the centre point of the blob but there's no guarantee it's the actual centre point of the plane. While indicating there's something there, it doesn't tell you what is there, it could be anything:
Quoting BlueShamu330s (Reply 42): Agreed. You can't, because you can't protect from pop-ups, echoes, dense flocks of birds, high-sided vehicles going over raised bridges, intense weather etc.
All of which will result in ghost targets you don't want. Also there's no way to match each of the returns from the last scan with each of the returns from the current scan. With 100+ blobs there's no way to guarantee any pair from 2 separate scans have come from the same source. If we can't guarantee the mapping accuracy, there's not way such routines can get into the PSR processing logic. It wouldn't pass the safety assessment.
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