Lack of radar service Offshore/Multilateration
SAS things have changed slightly - we do not fly along VOR radials, rather along gps tracks called HMRs. However, when crossing HMRs (radials to you!) we have to have a method of reporting position that everyone understands, so we use bearing and distance from the ADN VOR, but since VORs are pretty inaccurate or out of range, we use the gps bearing and distance from the ADN waypoint.
That means we can all give a pretty accurate position indication that is easy to understand (much harder if we were to give lat and long) and common to all operators OR SO I THOUGHT until we found last year that a certain fleet had an out of date magnetic variation table in its GPSs - gps need mag var to convert the true gps bearing from the ADN waypoint to magnetic.The data was many years out of date so the bearings reported were off by several degrees. Several degrees at 120nm = a lot of lateral error! All fixed now but just goes to show how easy it is to get it all horribly wrong!
HC
That means we can all give a pretty accurate position indication that is easy to understand (much harder if we were to give lat and long) and common to all operators OR SO I THOUGHT until we found last year that a certain fleet had an out of date magnetic variation table in its GPSs - gps need mag var to convert the true gps bearing from the ADN waypoint to magnetic.The data was many years out of date so the bearings reported were off by several degrees. Several degrees at 120nm = a lot of lateral error! All fixed now but just goes to show how easy it is to get it all horribly wrong!
HC
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Nice to see HeliComp climb down from his original view of whether the radar coverage is a good idea!!
Of course, anybody but a twit would advocate otherwise. It staggers me, that here is a wonderful system in offshore Scatsta and Sumburgh that works a treat (and the offshore radar is based in the Norwegian sector).
Compared to working offshore Aberdeen, where you may as well be in a Cessna 150 asking for FIS, the Northern North Sea is a pleasure to fly in, with the radar coverage; thanks to Norway.
Of course, anybody but a twit would advocate otherwise. It staggers me, that here is a wonderful system in offshore Scatsta and Sumburgh that works a treat (and the offshore radar is based in the Norwegian sector).
Compared to working offshore Aberdeen, where you may as well be in a Cessna 150 asking for FIS, the Northern North Sea is a pleasure to fly in, with the radar coverage; thanks to Norway.
MrR
Yes, I have been kind of back-pedalling since the start! But it was just in response to the scaremongering comment "how long do we put up with this dangerous practice " - at first I thought that stabout was probably from the press (until I did my homework). So let me clarify my position, of course multilat is a good thing but if its delayed by a year, that is frustrating but does not have a critical impact on overall safety levels in the N Sea.
Yes the secondary radar provided by the Norwegians is good, but don't forget you are flying to a pretty small area that can be covered by one radar. For the Aberdeen routes a lot more installations would be required and if its hard to install multilat antennae with no moving parts, its much harder to install a rotating radar head ( and both only work on transponder returns)
HC
Yes, I have been kind of back-pedalling since the start! But it was just in response to the scaremongering comment "how long do we put up with this dangerous practice " - at first I thought that stabout was probably from the press (until I did my homework). So let me clarify my position, of course multilat is a good thing but if its delayed by a year, that is frustrating but does not have a critical impact on overall safety levels in the N Sea.
Yes the secondary radar provided by the Norwegians is good, but don't forget you are flying to a pretty small area that can be covered by one radar. For the Aberdeen routes a lot more installations would be required and if its hard to install multilat antennae with no moving parts, its much harder to install a rotating radar head ( and both only work on transponder returns)
HC
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North sea full coverage
Interesting article
£5m system to track offshore air traffic soon to go live - Press & Journal
Can anyone add to this ?
£5m system to track offshore air traffic soon to go live - Press & Journal
Can anyone add to this ?
Why does this article keep referring to 'Emergency Situations' ???
The whole point of 'pseudo radar' coverage offshore is for normal day-to-day operations outside of line of sight radar signals. It is there to stop Emergency situations arising in the first place, and a very welcome addition to an already excellent ATC service.
The whole point of 'pseudo radar' coverage offshore is for normal day-to-day operations outside of line of sight radar signals. It is there to stop Emergency situations arising in the first place, and a very welcome addition to an already excellent ATC service.
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This is the "multilateration" system that ATC have been trying to get in place for a few years. It would have been in a lot earlier if the oil companies had freed up beds offshore so that the NATS teams could get the receivers in place. 
As it is not all of them are there yet.
For details on how it works take a look at Multilateration.
As it is not all of them are there yet.For details on how it works take a look at Multilateration.
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There is pretty good radar coverage for the guys down south.
Multilat's for outside 80 / 90 miles (135.175) off Aberdeen
Multilat's for outside 80 / 90 miles (135.175) off Aberdeen
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£5m system to track offshore air traffic soon to go live - Press & Journal
As this went to press , Planeplotter was just finishing multilateration trials for the whole of the UK....at a cost of , well , nothing , other than the hundreds of volunteer man hours !
Three months down the line we have about 50 ground stations active most of the time with good coverage down to 3000 feet...even better in many areas.
The North Sea must have been a piece of cake compared to the terrain environment of the mainland.
Of course a PP user can only handle one target per broadband connection , but thats purely down to server constraint.
It will be interesting to see how much the "official" UK Multilateration network will cost , when it eventually gets off the ground.
As this went to press , Planeplotter was just finishing multilateration trials for the whole of the UK....at a cost of , well , nothing , other than the hundreds of volunteer man hours !
Three months down the line we have about 50 ground stations active most of the time with good coverage down to 3000 feet...even better in many areas.
The North Sea must have been a piece of cake compared to the terrain environment of the mainland.
Of course a PP user can only handle one target per broadband connection , but thats purely down to server constraint.
It will be interesting to see how much the "official" UK Multilateration network will cost , when it eventually gets off the ground.
As far as I know its still in the commissioning stage - ie being tested / checked but not actually being used to provide us with a service (though I haven't flown for a while). Once its fully on stream I think it will be of tremendous benefit. Not quite sure what your agenda is, you seem negative about it, why?
HC
HC
Not what National Air Traffic Services told the press!
I am aware that live data has been being monitored for some time (at least since November) but with it being a system where accuracy, integrity and reliability are critical for flight safety, the testing and proving phase should not and is not being skimped.
Patience is a virtue (or so they say).
The negativity comes out in the tone of your post but as always with the written word, may be open to misinterpretation. But you clearly had some agenda for posting, otherwise why bother?
HC
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Has any body noticed that the FAA is initiating ADS/B for the platforms in the Gulf of Mexico. Any chance of the the CAA doing the same for the North Sea. Sigh! Dreams, dreams.
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The Dutch are doing a combination of multilateration and ADS/B. Total overhaul of route structure and comms as well. Aim is to have 2 way comms and blip on screen at average helideck level in entire offshore part of FIR.
Should be close to testing phase.
And on this project the oil companies were participants and are stakeholders.
Should be close to testing phase.
And on this project the oil companies were participants and are stakeholders.
And on this project the oil companies were participants and are stakeholders
How to, I think where HC detected the negativity (as I did) was in this statement:
More dosh in the pocket of oil/heli companies?
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The radar head at Ekofisk has been cancelled because an agreement could not be reached with ConocoPhillips about the placement.
Sad really.
Heidrun radar is going live with a Class D CTA soon, and they are working with ICAO to get Statfjord CTA moved from Class E to D.
Ekofisk has been put on the back burner, waiting to get ADS-B coverage in the future. Multilateration not possible because the platforms are placed more or less on a line, so accuracy would be poor.
Sad really.
Heidrun radar is going live with a Class D CTA soon, and they are working with ICAO to get Statfjord CTA moved from Class E to D.
Ekofisk has been put on the back burner, waiting to get ADS-B coverage in the future. Multilateration not possible because the platforms are placed more or less on a line, so accuracy would be poor.
rotorfossil / S76 Heavy
As far as I am aware the Multilat system in the N Sea is capable of using ADS-B data from appropriately equipped aircraft. If the aircraft has no ADS-B then it needs to triangulate the transponder transmissions and therefore you need to be in range of several (3 I presume) Multilat receiver aerials. If you have ADS-B then only 1 antenna is needed to pick up your extended squitter info which includes your position and a measure of the integrity thereof.
I find it frustrating that operators are continuing to buy new aircraft without ADS-B. Having identified the issue a year or so ago, the last 6 or so EC225s that Bristow has taken delivery of have ADS-B though 4 of those are now in Australia (ie 2 in the N Sea).
To have ADS-B on the 225 is a doddle - you just need to ensure that EC fits the latest dash-number of the transponder box (TDR94D -409) and connects a twisted pair of wires between the GPS and the Transponder. Not that difficult really and minimal cost!
It has other advantages such as Skywatch not needing to direction-find your bearing with dodgy DF antenna, rather it can just read your gps position, it knows its own gps position and so your bearing and distance is calculated using geometry - much more accurate than DF.
Even to retrofit older aircraft normally just needs an SB applied to the transponder box to bring it up to date, that wire between the GPS and the TDR. Older GPSs had problems outputting the necessary parameters for NIC NAC and SIL to be calculated by the TDR, but even the trusty old Trimble / Freeflight 2101 now does it having had a software update. If I was in charge all offshore helis would be modified to have ADS-B!
I think the problem is that the powers that be, including those who order new aircraft, have no idea about this technology and how straightforward it is to implement. Frustrating!
HC
As far as I am aware the Multilat system in the N Sea is capable of using ADS-B data from appropriately equipped aircraft. If the aircraft has no ADS-B then it needs to triangulate the transponder transmissions and therefore you need to be in range of several (3 I presume) Multilat receiver aerials. If you have ADS-B then only 1 antenna is needed to pick up your extended squitter info which includes your position and a measure of the integrity thereof.
I find it frustrating that operators are continuing to buy new aircraft without ADS-B. Having identified the issue a year or so ago, the last 6 or so EC225s that Bristow has taken delivery of have ADS-B though 4 of those are now in Australia (ie 2 in the N Sea).
To have ADS-B on the 225 is a doddle - you just need to ensure that EC fits the latest dash-number of the transponder box (TDR94D -409) and connects a twisted pair of wires between the GPS and the Transponder. Not that difficult really and minimal cost!
It has other advantages such as Skywatch not needing to direction-find your bearing with dodgy DF antenna, rather it can just read your gps position, it knows its own gps position and so your bearing and distance is calculated using geometry - much more accurate than DF.
Even to retrofit older aircraft normally just needs an SB applied to the transponder box to bring it up to date, that wire between the GPS and the TDR. Older GPSs had problems outputting the necessary parameters for NIC NAC and SIL to be calculated by the TDR, but even the trusty old Trimble / Freeflight 2101 now does it having had a software update. If I was in charge all offshore helis would be modified to have ADS-B!
I think the problem is that the powers that be, including those who order new aircraft, have no idea about this technology and how straightforward it is to implement. Frustrating!
HC
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Getting the appropriate equipment proved to be a major hurdle for the Dutch authorities..with some of the operators and/or manufacturers dragging their feet.
For some of the older aircraft it was not a question of a "plug and play" feature, exacerbated by bean counter mentality in some quarters.
The whole point of triangulation is to give adequate traffic information to offshore ADS/B equipped helicopters with regard to non-ADS/B but squawking crossing traffic in the busiest and largets part of the area, both civil and military. At the far edges of the FIR the risk of conflict with non-offshore traffic is small and the ADS/B provides the basis for Alerting Service/Flight watch.
For some of the older aircraft it was not a question of a "plug and play" feature, exacerbated by bean counter mentality in some quarters.
The whole point of triangulation is to give adequate traffic information to offshore ADS/B equipped helicopters with regard to non-ADS/B but squawking crossing traffic in the busiest and largets part of the area, both civil and military. At the far edges of the FIR the risk of conflict with non-offshore traffic is small and the ADS/B provides the basis for Alerting Service/Flight watch.
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I was mightily impressed seeing ADS/B in action in Alaska. All participating traffic's position, track and altitude overlayed on the terrain picture in the cockpit. The difference in confidence level from this and dodgy radar based information from ATC due to terrain masking made the point in some distinctly poor vis and low cloud.
However one has to admit that the FAA were funding all the ground stations and provided the first 100 odd aircraft fits FOR FREE so that a realistic trial could be made.
However one has to admit that the FAA were funding all the ground stations and provided the first 100 odd aircraft fits FOR FREE so that a realistic trial could be made.