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Air Traffic Control out in Sweden
Hi, I read newspaper articles that there was an outage of air traffic control in Sweden on the 4th of November. Anyone have Details ? What didn´t work anymore ?
Thanks . |
Procedural isn't taught in many places anymore, and how comfortable would you be sitting down with paper and a pencil and doing it for the first time in a few decades with live traffic?
I certainly wouldn't be. |
There are no procedures except land as soon as possible.
If the geomagnetic disturbance from the flare is severe enough, radio doesn't work, radar doesn't work, and GPS signals are lost. Radio based navigational aids will also fail or be unreliable.
So strict VFR flying conditions with no external contact between aircraft and the ground or other aircraft and no navigational information except eyeballs and paper charts. Even that may not work if compasses are inaccurate, as they often are that far north in geomagnetic storm conditions. Still want to fly? Sometimes we just have to recognise that nature is bigger than our technological solutions. |
Procedural really ought to be taught & be available. However, keeping proficient enough to be able to use it I in a serious situation with lots of traffic is problematical. it was abandoned partly because of the reliability of Radar systems, but also as a cost saving matter. I think that the cost saving element was given far too high a priority & that Procedural training should have continued.
I also have to reflect that when undergoing TRUCE training, ATCOS at my unit, who had no experience of controlling without SSR, were at a complete loss of how to continue Radar Control using PRI only. This is highly regrettable & ought not to be allowed. But, that is the modern way, & every penny counts ! |
You may find that London Control is not authorised to provide a non-radar service except for short term clear the sky purposes.
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I have to admit that it is very hard to imagine any effective sort of Procedural Control taking place in the very busy, & complicated , airspace that we have now. But, it would be a useful tool for ATC to use to provide some sort of service when Radar is u/s. Although, it should be possible to provide back-up Radar within a short while of a failure in the service.
Let's face it, if the Radar fails in busy airspace, it is an emergency situation which can only be resolved effectively by the use of a replacement Radar service. But, I continue to feel that Procedural experience & ability could help in the provision of a safe contingency ATC service, both in the immediate aftermath of the Radar failure & in the longer term, before the Radar is restored. |
hmmm....so, Radar didn´t work, and the newspaper didn´t mention GPS. I guess that worked fine, then. Were any notams out ?
Procedural control must be quite difficult with many planes in the sky.... I think I´d like to stay out of and area where this is done, if I had a choice. |
A friend of mine who works at Sweden Control (but was not at work during the incident) tells me that the MSSR system (1030/1090 MHz) was compromised such that the same aircraft could be displayed up to 10 times along a 20-30 mile track. The disturbance was "medium", which is ironic; if the disturbance had been stronger, the system would have filtered out the bad echoes by itself. The "medium" strength probably explains why the event was not accompanied by increased auroral activity. We've had a few aurora nights at 64N in the recent weeks, but this clear night showed none (bummer).
My friend also stated that procedural routes have either to be purely VOR-based or defined (and approved by the authorities) as "separated", neither of which is common in Scandinavia any more. Overflying traffic was not affected as they could easily be separated by altitude. I have heard no report of affected GPS signals nor observed any unusual anomalies (on the ground) myself. Since GPS operate near MSSR frequencies, it would be expected that it too experienced anomalies. My speculation is that if GPS was less largely hit, the difference might be explained by the difference in signal travel direction between MSSR (effectively horizontally) and GPS (more slanted towards vertical, even at 60+ deg north). His comment that the radar system can filter out strong disturbances intrigues me. Could this be an "automatic" effect because the return signal would appear outside some tight tolerance defined by the Mode A/C/S protocol or is it more likely it is handled in an additional software layer? Any comment from an RF/MSSR-knowledgeable person would be appreciated. (Edit) The end result was that aircraft in the air were allowed to land but no domestic aircraft were allowed to take off. Don't know about international departures. Normal OPS were restarted after about 1.5 hours. (/Edit) (Edit 2) After re-reading the media report of that day (http://www.dn.se/nyheter/sverige/sol...ll-radarstopp/) I can add the following: All radar stations that were affected had the sun above the horizon. All false radar echoes appeared within an 8 degree narrow sector in the sunward direction. (/Edit 2) /N |
LookingForAJob
I could not agree with you more ! I know that the statistics give comfort to "those that matter", but they give no comfort to me. As I have said before, my generation of ATC was schooled (& submersed) in the "when the system fails, it fails safe" philosophy. For me, it is difficult to imagine that this philosophy is upheld in modern systems & methods. However, it is difficult to accuse those in charge of having a cavalier attitude in this matter when the statistics do not make an obvious flaw in safety standards apparent. I do believe that there is such a flaw underlying the system, but it may never make itself obvious to the ANSPS, the regulators, the bean counters, the general public, or even to the ATCOS. Long may that continue to be the case ! In general, it may have to be accepted that the modern system & philosophy of ATC is the ONLY way to deal with the traffic load. In that case, "Goodbye Procedural ATC". |
Sumburgh, Shetland Islands also had a radar outage for about an hour at the same time.
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hmm, shetlands, too ? Well, they are about at the same N latitude as Sweden.
I wonder why Norway and Denmark didn´t have Problems... Found a solar Radio burst on https://twitter.com/thesuntoday , but don´t know if it is relevant Re procedural control: can´t really remember having flown that for real during the last decades. So, no real practice - and I don´t think that todays traffic could be handled procedurally.....in London, Frankfurt, Stockholm... best |
Klauss, thanks for the link. The timing and length of the event in the plots is consistent with the outage. Too bad that the monitored frequencies stop at 400MHz, but it stand to reason that the 1GHz band was affected too.
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This is fine, particularly for the beancounters who have a great say in how airlines are run. |
I think so, too, but I am still looking for evidence. There are a few other stations that Monitor to 800 Mhz, but they don´t seem to have the same burst . No idea why....not a scientist....
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I wrote about this in the Nordic Forum when it happened.
The people from Luftfartsverket claimed that the solar flares disturbed radar enough that it would sometimes show doubles of planes, and sometimes the planes disappeared. The disturbance lasted about four hours plus minus. It was low intensity flares so the automated system didn't filter the erroneous data because it was calibrated for larger events. |
thanks for the hint - the newspaper article makes it clear that the SSR was in trouble, not the real radar. Looks like a strong radio burst fromt the sun played a role, but I guess the definite failure reason will take some time to determine.
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and FR24 wasn't in trouble either :):)
Joking apart, a bit strange that Mode S - ADS-B based flight surveillance info (provided by 'consumer product' class of hardware) was available, without AC appearing tenfold. And top notch professional SSR was having trouble. And the Olso boys and girls (left side of the picture) didn't seem to care either, while Swedish airspace was emptying out. http://www.anony.ws/i/2015/11/11/FR2...naviaSolar.png |
That is why scientists are questioning the solar flare theory, DIBO.
I do not have access to the systems used on ARN et al, but I do know they have had some small problems now and then, ARN even had to close for a few hours and then a NOTAM to always carry enough for diversion was placed. (This was maybe a year ago, the NOTAM is lifted now...) It is, in my mind, very possible that this might have been a glitch that happened to manifest during a solar flare, instead of the solar flare causing the glitch. The strange distribution of the flares and the complete lack of flares in Norway and Denmark is indeed very puzzling. |
well, yes, it´s curious that there wasn´t anything wrong in the surrounding countries.
I still believe that the sun had a great deal to do with the Event. There was a medium strong disturbance going, in all aspects (ionosphere, magnetic etc.) and on top, there was the Radio burst. It was even registered in Finland. Links: Observatory:http://metsahovi.aalto.fi/en/research/sun/ Observation:http://www.metsahovi.fi/~kallunki/So...t/20151104.txt The swiss observatory had it, too, including 1000.....1250 Mhz whichis where the SSR works. So....some electrons found a way that´s not ok, and therefore, SSR failed. SSR ? Well, the describtion in the newspaper article from sweden....says as much.Hight info, identification... Interesting subject. |
the newspaper article makes it clear that the SSR was in trouble, not the real radar a bit strange that Mode S - ADS-B based flight surveillance info (provided by 'consumer product' class of hardware) was available, without AC appearing tenfold. |
I was ready to go at KUO (Finland) at 15:15z when we were told that Sweden Radar was down and a CTOT 1:35hr later was given. Suddenly 25 mins later we were cleared to start. Normal radar service through Sweden.
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eglnyt
No information I have encountered mentions Primary or Secondary Radar. What is known is that military radar continued to work. Luftfartsverket are adamant about the solar flares: LFV utreder onsdagens radarstörning - www.lfv.se LFVs initiala analys visar en tydlig korrelation mellan tiden för solstormen och störningarna i radarsystemen. Ett antal radarstationer blev överbelastade och behövde startas om. – Vi kommer nu att utreda konsekvenserna av gårdagens händelse, fortsätter Olle Sundin. The first analysis by LFV shows clearly a link between the time for solar storm and the disturbances in radar systems. A number of radar stations was overloaded and needed to reboot. - We will now investigate the consequences of yesterday's incident, Olle Sundin continues. |
...thanks for the News. I wonder if there will be an official Report, or if this is it ?
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Hi, is there any news from Sweden ?
Space wx confirmed as reason , or was there an other failure reason suspected ? Thanks |
Interesting debate drawing similarities between flight deck and ATC system issues in terms of reliance on technology and the atrophy of 'manual skills'.
One important difference though. If a modern aircraft suffered a control system failure, then the flight crew would aim to put it on the deck ASAP. The ATC system as a whole, where technology is integral to the service, such as in most of Europe, aims to do the same in the case of a major failure. Get everything safely on the ground, or to other airspace. And yet we seem to be expecting the ATC system to carry on manually, with no radar, or with handwritten, paper strips. Isn't that the same as expecting the flight crew to get into their broken jet and fly another load of passengers on another flight using backup and or manual systems? Do we feel comfortable with that? |
But Gonzo if the electronic strips go there is no paper backup either. I'm relying on my goldfish brain.....
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Yes, that was my point.
I think. Many electronic strip-equipped towers started off with reverting to paper strips as the contingency. The further we go, the greater the proportion of ATCOs have no experience of paper strips (or procedural ATC, or any other 'old school' way of controlling). Is it fair to expect that we should continue planning to use such methods for contingency? Or do we accept that modern ATM systems are required, and if we lose them then we either shut the whole thing down, or we run at a very, very reduced capacity. Don't forget that the support staff required to run a 'manual' operation are in many cases no longer there. Terrain Safe, you're not expected to keep the operation going at the same level without electronic strips though. Are you? |
Turns out the events coincided with a massive cyber attack against Sweden.
https://www.aldrimer.no/sweden-issue...raffic-reeled/ |
Originally Posted by appletini
(Post 9343208)
Turns out the events coincided with a massive cyber attack against Sweden.
https://www.aldrimer.no/sweden-issue...raffic-reeled/ |
First official report
The first official "report" of the event was published today at LFV's (the ATC operator) website:
LFV levererade full kapacitet 90 minuter efter radarbortfall TL;DR: Cause: Solar flares combined with (un)favourable sun angle w.r.t. the radar stations (near sunset). Radar screens were back to normal after 45 minutes, full airspace capacity restored after 45 more minutes. Google translate of webpage: The investigation that LFV has done for radar interference in November 2015 shows that the reason was the radio radiation associated with solar flares. Radar shortfall came to affect parts of the air traffic in Sweden. It was on Wednesday, November 4, 2015 at 16 o'clock that one of the control centers in Stockholm and Malmö were the first indications that LFV's radar did not deliver correct data to the flight line. The cause was quickly identified and action taken. - When the disturbance occurred was the air traffic controllers could not use the information on the radar screens of the alternative ways to lead aircraft, says LFV's technical director Ulf Thibblin. For LFV air safety a top priority. If the aircraft for various reasons, unfavorable weather or technical problems, can not be guaranteed reduced airspace capacity. It has been discussed in recent days that the radar interference were not related to space weather, but that it instead was due to a cyber attack against Sweden. - In our investigation we had early on with it as a hypothesis. There was nothing in our radardata- or Internet traffic logs to support or confirm a possible cyber attack. Also, we had the relationship in time with space weather, plus there were a few more technical reasons which excluded a cyber attack, says Ulf Thibblin. After the radars had rebooted had LFV air traffic controllers correct radar presentation 45 minutes after the disturbance, and after another 45 minutes it was at full capacity in the airspace. LFV radars have been affected in a similar way two times in the last 17 years - 1999 and 2003. The disturbance then and now occurred at sunrise or decline when the sun's angle is straight into, or virtually straight into the radar facility. According to experts in the field it is possible to predict a solar flare but not its consequences, such as radio frequency radiation. As the shock travels at the speed of light from the sun to the earth, there is no opportunity to receive a notice in confirmed cases. CAA radar facilities around Sweden continuously upgraded and will gradually be supplemented by a new type of monitoring, wide area multilateration, which means that LFV increases its robustness significantly. |
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