North Sea News
Yes, the GoM does look a big one (ooer missus) and rather makes my point that if you were going for the further helideck, you would have collided with the nearest part of the structure before 1/4sm!
SASLess,
HC's concern is about the reference point from which the MAP is located. The only way this can work with such low mimima is if the approach is absolutely defined in terms of direction and offset; thus, each MAP will be defined with respect to the nearest part of the installation (to the MAP) and will apply only to specific approach (it could be bi-directional of course).
Because the go-around will have to be directly ahead, if the obstacle avoidance distance is the same as the distance of the MAP, at the MAP the helicopter will be adjacent to the rig and it will appear in the side window!
The way to avoid this is to reduce the miss-distance from the installation in the go-around; less than 1/4 SM is quite close when all errors are taken into consideration.
I thought that the main reason for automating the approach was to minimise the work on the visual segment; reducing the distance of the MAP doesn't do this, it increases the workload and puts it into a shorter distance (and time).
My experience is that we lose only a tiny percentage of flights from weather related causes. It would be interesting to see the safety case (potential gains v increased risk of collision) from reducing the MAP.
Jim
HC's concern is about the reference point from which the MAP is located. The only way this can work with such low mimima is if the approach is absolutely defined in terms of direction and offset; thus, each MAP will be defined with respect to the nearest part of the installation (to the MAP) and will apply only to specific approach (it could be bi-directional of course).
Because the go-around will have to be directly ahead, if the obstacle avoidance distance is the same as the distance of the MAP, at the MAP the helicopter will be adjacent to the rig and it will appear in the side window!
The way to avoid this is to reduce the miss-distance from the installation in the go-around; less than 1/4 SM is quite close when all errors are taken into consideration.
I thought that the main reason for automating the approach was to minimise the work on the visual segment; reducing the distance of the MAP doesn't do this, it increases the workload and puts it into a shorter distance (and time).
My experience is that we lose only a tiny percentage of flights from weather related causes. It would be interesting to see the safety case (potential gains v increased risk of collision) from reducing the MAP.
Jim
Student.....as in Real Estate....when doing an Appraisal one should select "com parables" and not just settle for the first thing that pops up.
There are zillions of Toad Stools in the GOM, gobs of small platforms, Rigs of all sizes and kinds, along with platforms that are very similar to those in the North Sea.
JimL,
Is the FAA perspective in this the same as the CAA? I gathered the FAA is looking at keeping the offset but dropping it to a quarter mile and using a 200 foot Ceiling. Have we not used a Quarter Mile offset in the past for Rig Radar Approaches?
If my alcohol ravaged brain does not let me down....did not the original Radar Approaches have us flying directly towards the Rig then making an immediate turn at the MAP of a quarter mile? How many times we get a real fright to see the Derrick Dog House whiz by the chin bubbles?
The article I linked is fairly vague and was not a detailed review by any means thus drawing too much from the article would be a stretch.
HC and you both make good valid points which I do not disagree with at all.
It is interesting to contemplate an automated landing system that places the Helicopter at a "Decision Point" that would place the helicopter in such a position that the Pilot could use "Trim Buttons" to continue the Visual Approach while using the Automated Control System.....kind of like the Bristow SAR guys up at that small island north of Skye have done in the past when going up the Seaplane Ramp. (Or something similar as I have heard from Reliable Sources).
The Technology is here. The Computer power is here. The Radar inputs, GPS inputs, Doppler Inputs, and even Look Ahead FLIR, could all be accessed to provide for obstacle clearance and course guidance for the Automated Flight Control System.
Getting the Authorities to embrace that Techology is the major hurdle as I see it.
If the current system can bring you to a stabilized hover over a given point, at a given height, why all this concern about running into something?
The system might not work for all locations for various reasons....but for Platforms that are firmly mounted to the Bottom....I can it being very easy to develop safe approach corridors. As in the article....plug in the data to the FMS, then let trusty old George fly the approach....even if you do not arrive at a hover.....you can at least arrive at a very slow ground speed which would make the transition much easier.
We may not miss many landings due to weather....but we do seem to park aircraft in the Oggin at night while doing these landings. Night time is when the automated approach would prove most useful. The Computer has a digital brain that is far more reliable than a human with Mark One Eyeballs trying to interpret what they are seeing outside and comparing it to what they see inside.
There are zillions of Toad Stools in the GOM, gobs of small platforms, Rigs of all sizes and kinds, along with platforms that are very similar to those in the North Sea.
JimL,
Is the FAA perspective in this the same as the CAA? I gathered the FAA is looking at keeping the offset but dropping it to a quarter mile and using a 200 foot Ceiling. Have we not used a Quarter Mile offset in the past for Rig Radar Approaches?
If my alcohol ravaged brain does not let me down....did not the original Radar Approaches have us flying directly towards the Rig then making an immediate turn at the MAP of a quarter mile? How many times we get a real fright to see the Derrick Dog House whiz by the chin bubbles?
The article I linked is fairly vague and was not a detailed review by any means thus drawing too much from the article would be a stretch.
HC and you both make good valid points which I do not disagree with at all.
It is interesting to contemplate an automated landing system that places the Helicopter at a "Decision Point" that would place the helicopter in such a position that the Pilot could use "Trim Buttons" to continue the Visual Approach while using the Automated Control System.....kind of like the Bristow SAR guys up at that small island north of Skye have done in the past when going up the Seaplane Ramp. (Or something similar as I have heard from Reliable Sources).
The Technology is here. The Computer power is here. The Radar inputs, GPS inputs, Doppler Inputs, and even Look Ahead FLIR, could all be accessed to provide for obstacle clearance and course guidance for the Automated Flight Control System.
Getting the Authorities to embrace that Techology is the major hurdle as I see it.
If the current system can bring you to a stabilized hover over a given point, at a given height, why all this concern about running into something?
The system might not work for all locations for various reasons....but for Platforms that are firmly mounted to the Bottom....I can it being very easy to develop safe approach corridors. As in the article....plug in the data to the FMS, then let trusty old George fly the approach....even if you do not arrive at a hover.....you can at least arrive at a very slow ground speed which would make the transition much easier.
We may not miss many landings due to weather....but we do seem to park aircraft in the Oggin at night while doing these landings. Night time is when the automated approach would prove most useful. The Computer has a digital brain that is far more reliable than a human with Mark One Eyeballs trying to interpret what they are seeing outside and comparing it to what they see inside.
Last edited by SASless; 4th Jul 2013 at 17:14.
Jim - I would say we do lose quite a percentage of flights due to not seeing the rig, compared to virtually none from having to go-around from an ILS. Although they both have a nominal minimum height of 200' in the case of the ILS, one only has to see the lights looking mostly downwards through 200' of cloud. Lets say the slant range is 300'. So even with cloud on the surface, provided its not too thick you will still get in. For offshore, at 200' you have to look through 3/4 mile of cloud - more than 10 times as much - so if you are in the bottom of the slighest bit of cloud, you won't see the installation.
SAS - limits on N Sea have been, for nearly as long as I have been flying on it, offset at 1.5 miles then continue to 0.75 miles range from the nearest bit of structure (front of radar blip). I think it used to be 0.5 miles in the late 70s but was never 0.25 AFAIK.
Although the technology certainly exists (and is installed in the EC225 amongst others) to effectively auto-hover-taxi from MAP to destination, in practice one can get very disorientated and of course the failure of the system has to be taken into account so that the pilot can recover safely. In the case of auto-hover over the ocean for SAR, you can just go ahead and up which is not too bad, but if there is a large chunk of metal just ahead it all gets rather more tricky.
SAS - limits on N Sea have been, for nearly as long as I have been flying on it, offset at 1.5 miles then continue to 0.75 miles range from the nearest bit of structure (front of radar blip). I think it used to be 0.5 miles in the late 70s but was never 0.25 AFAIK.
Although the technology certainly exists (and is installed in the EC225 amongst others) to effectively auto-hover-taxi from MAP to destination, in practice one can get very disorientated and of course the failure of the system has to be taken into account so that the pilot can recover safely. In the case of auto-hover over the ocean for SAR, you can just go ahead and up which is not too bad, but if there is a large chunk of metal just ahead it all gets rather more tricky.
And potentially quite noisy for a few moments!
An interesting topic which my jet lagged brain (just arrived from BWN-KUL-LHR flight) won't allow sensible input to, other than it highlights the misconception that the MAPt has anything to do with the ability to land. A true MAPt has relevance only to the protected missed approach and the point from which a safe landing can be made may have been well passed. I see this a lot when discussing the CDFA NPA concept with RW pilots.
Time for a snooze.....
Time for a snooze.....
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JimL wrote
Jim, the approach can be carried out from any direction to the rig or platform and is usually oriented into wind with the MAPt worked out from the applicable direction of the approach.
The only way this can work with such low mimima is if the approach is absolutely defined in terms of direction and offset; thus, each MAP will be defined with respect to the nearest part of the installation (to the MAP) and will apply only to specific approach
Doeppner explained that “it will take the pilot approximately 20 seconds to build the approach.” He has to enter four variables: the destination waypoint (the rig coordinates), the inbound course (into the wind), the minimum descent height (50 feet above the landing platform) and the offset direction (left or right) and distance. “Those steps can be accomplished at any time but usually 20 to 50 miles from the rig,” Doeppner said. Once the approach is built, the pilot presses a single button and the aircraft automatically flies the approach.
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I think the only point really being made is dependant on size, what point of a possibly HUGE platform is your MAPt based on. If it is the centre of the structure then you will have the same distance from all four points of the compass, if the heli deck then that will be a different distance from the structure depending which way the pad sticks out. A smaller platform like some in GOM and southern north sea will be less of a problem but the larger one's will need to be considered carefully. Like HC has said the Ekofisk is HUUUGE and where is your datumn point on that monstrosity?
Si
Si
Which Deck you talking about using on the Ekofisk? Each approach to the various decks would have different obstacles to be concerned about depending upon the wind direction and azimuth of approach and offset required to avoid the Structures.
Last edited by SASless; 5th Jul 2013 at 02:36.
My understanding is that the very low offset values will only be used to properly surveyed fixed platforms, and the actual offset distances will vary with the approach direction (for the reasons highlighted above) and will be published on the OSAP/ARA chart. There is no suggestion that the pilots will leave it to random guess work, and mobile installations will need higher offsets.
Regarding the point about landing and decoupling, the Flight Director ends up in velocity and Radalt hold in the final stages of the approach, with a 30kts ground speed. The intent is to not decouple immediately, but to use the cyclic beep switch to adjust the velocity vector's direction and speed towards the deck. Decoupling can take place at a very late stage. It's effectively an adaptation of the SAR AFCS. I've tried it in the simulator and it's very impressive.
I think one of the greatest benefits will be for night approaches and DVE conditions - other than simple cloud break - as that is where most of the offshore accidents have occurred in the last 20+ years.
There's just that small question of cost now
Regarding the point about landing and decoupling, the Flight Director ends up in velocity and Radalt hold in the final stages of the approach, with a 30kts ground speed. The intent is to not decouple immediately, but to use the cyclic beep switch to adjust the velocity vector's direction and speed towards the deck. Decoupling can take place at a very late stage. It's effectively an adaptation of the SAR AFCS. I've tried it in the simulator and it's very impressive.
I think one of the greatest benefits will be for night approaches and DVE conditions - other than simple cloud break - as that is where most of the offshore accidents have occurred in the last 20+ years.
There's just that small question of cost now
Last edited by 212man; 5th Jul 2013 at 06:28.
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New Deep Water prospects for UK
ABERDEEN, Scotland. Published: July 23, 2013 — Chevron oil has said today that it would spend $770 million, on its planned Rosebank and Alder oil and gas development projects in British waters.
http://www.nytimes.com/2013/07/24/bu...obal-home&_r=0
Rosebank, an oil and natural gas field, is on what is becoming one of Europe’s key fossil-fuels frontier areas, the margins of the Atlantic Ocean west of the Shetland Islands off Scotland. Alder, holding gas, is in the central North Sea, which is also attracting major new investments. Northeast Scotland has evolved into the hub of Britain’s and in some respects Europe’s oil industry, with hundreds of suppliers of high-tech services and undersea gear.
Rosebank has required years of work because of the field’s tricky geology. The oil is contained in layers of sandstone sandwiched between volcanic basalt rock, which is difficult to penetrate with seismic imaging technology that the industry uses. Mr. Klein said that to obtain better images of the oil and gas, Chevron put 750 sensors on the sea bottom in 2010 and 2011 and then spent two years analyzing the resulting data. “There is less uncertainty than three years ago,” he said.
Chevron executives in Aberdeen said that recent changes in the British tax system, giving allowances of up to 3 billion pounds for deepwater projects in the area, had made the project viable in Chevron’s portfolio, assuming that oil fields earn $25 per barrel or more. Rosebank, which is in 1,100 meters, or 3,600 feet, of water and is being designed to survive waves of 30 meters, is believed to be the only project that would qualify for those allowances so far.
Rosebank has required years of work because of the field’s tricky geology. The oil is contained in layers of sandstone sandwiched between volcanic basalt rock, which is difficult to penetrate with seismic imaging technology that the industry uses. Mr. Klein said that to obtain better images of the oil and gas, Chevron put 750 sensors on the sea bottom in 2010 and 2011 and then spent two years analyzing the resulting data. “There is less uncertainty than three years ago,” he said.
Chevron executives in Aberdeen said that recent changes in the British tax system, giving allowances of up to 3 billion pounds for deepwater projects in the area, had made the project viable in Chevron’s portfolio, assuming that oil fields earn $25 per barrel or more. Rosebank, which is in 1,100 meters, or 3,600 feet, of water and is being designed to survive waves of 30 meters, is believed to be the only project that would qualify for those allowances so far.
HC -
Seem to remember that when I started in Aberdeen in 1986 it was 0.45nm (don't know why it was not 0.5, but pretty sure it was 0.45), and that was with the old monochrome radars that had a much poorer definition than the newer ones.
I think it used to be 0.5 miles in the late 70s but was never 0.25 AFAIK.
Ant T
Yes, I agree, it was 0.45nm. When we had one of those green coloured RCA Primus 45 Radars, we wondered how technology could improve any more. Then came the Primus 500 colour radar with the grid lines, we couldn't believe our luck!
Hand flown approaches in the S-61 down to 150' rad alt and 0.45nm on minimum diversion fuel, them were the days!
Yes, I agree, it was 0.45nm. When we had one of those green coloured RCA Primus 45 Radars, we wondered how technology could improve any more. Then came the Primus 500 colour radar with the grid lines, we couldn't believe our luck!
Hand flown approaches in the S-61 down to 150' rad alt and 0.45nm on minimum diversion fuel, them were the days!
Howcanwebeexpectedtoflylikeeagles
whensurroundedbyturkeys
It was definitely 0.5nm and 150' until a BCal helicopter got it wrong and got very close to hardware on a go-around.
Having said that, I remember during my initial training with a NS company (which will remain nameless) many many years ago sitting on a S61 jump seat with two captains doing a VIP trip to a rig and observing a 50' ARA to a decision point of "when we see the rig" followed by a vertical climb up the side of the rig onto the helideck.
Changed days now, thank goodness, but looking forward to getting the automatics (and approvals) which perform an ARA equivilent and bring us to a hover alongside the helideck. They would have avoided my go-around today from a rig followed by a three hour stop at Sumbugh waiting for the weather to clear offshore to eventually get back to Aberdeen at both FTL duty hour limits and close to ILS weather limits followed by minimum rest before another 0600hrs start. Oh happy days! Am I getting too old for this? NO!
Having said that, I remember during my initial training with a NS company (which will remain nameless) many many years ago sitting on a S61 jump seat with two captains doing a VIP trip to a rig and observing a 50' ARA to a decision point of "when we see the rig" followed by a vertical climb up the side of the rig onto the helideck.
Changed days now, thank goodness, but looking forward to getting the automatics (and approvals) which perform an ARA equivilent and bring us to a hover alongside the helideck. They would have avoided my go-around today from a rig followed by a three hour stop at Sumbugh waiting for the weather to clear offshore to eventually get back to Aberdeen at both FTL duty hour limits and close to ILS weather limits followed by minimum rest before another 0600hrs start. Oh happy days! Am I getting too old for this? NO!
Last edited by HughMartin; 23rd Jul 2013 at 19:36.
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Does anyone remember the Madge approach on to the Beryl A with no DP in the S61N? You just followed the vertical and horizontal needle of a look alike ILS as it took you past the rig offset to one side 
Last edited by TipCap; 23rd Jul 2013 at 20:47.
The MADGE; a wonderful approach aid that would enable Hercules and suchlike to land on primitive strips in all weathers; the same for helicopters.
I was, in a small way, involved in the development of the kit in 1971. We had recently formed the first Puma squadron and the word in the rest of the helicopter world was that the Puma needed two days notice in writing to stop and come to the hover. This filtered through to RAE Bedford, who were trialling the MADGE. The O/C, whom I knew, asked us to go the Thurleigh and have a shot with the MADGE in order to assess whether a Puma could stop satisfactorily coming out of clag at 200 ft..
Two of us then flew up in a Puma to have a look at the problem. We got the brief on the kit; obviously we couldn’t use the Puma as it didn’t have the fit so we were going to fly the trials Wessex. There was a sense of urgency because at 13.00hrs the civil fire section was going on strike and the airfield would be closed; marooning us in Thurleigh.
My companion, ex 72 Sqn, went first whilst I chewed the rag with my old mate. He came back, we changed over, the LHS chap indicated that I had control and off we went. My enforced experience in the V Force ensured that flying a pseudo ILS was easy and there was no problem, as far as I could assess with a Puma at the DH it would stop quite happily.
I flew it back to the apron at Thurleigh and we landed at 12.55. The Puma was already burning and turning so I bid farewell to the safety pilot, jumped in the Puma and away we went back to Odiham.
It was a successful operation apart from two minor points:
1: The O/C trials unit had assumed that I was qualified on the Wessex, which I wasn’t. Having spent two tours in the Far East I had stacks of time on Whirlwinds but zero on the Wessex.
2: I had assumed the chap in the LHS was a pilot, which he wasn’t. He was a navigator or some other cave dweller with no idea about the Wessex and I had left him in the middle of one turning and burning in the middle of an airfield with no fire cover at lunchtime.
I had no trouble flying it; it was just two Siamesed Whirwinds. I think that the torquemeter’s needle, the Puma not having one in those days, may have ventured into unexplored territory.
My mate was dragged out of the dining room and rushed to his Wessex to shut it down as the occupant was having kittens over the radio. He telephoned to complain but after a very short time he realised what had really happened so he seemed to dry up somewhat.
I never did see or hear of MADGE in RAF service.
I was, in a small way, involved in the development of the kit in 1971. We had recently formed the first Puma squadron and the word in the rest of the helicopter world was that the Puma needed two days notice in writing to stop and come to the hover. This filtered through to RAE Bedford, who were trialling the MADGE. The O/C, whom I knew, asked us to go the Thurleigh and have a shot with the MADGE in order to assess whether a Puma could stop satisfactorily coming out of clag at 200 ft..
Two of us then flew up in a Puma to have a look at the problem. We got the brief on the kit; obviously we couldn’t use the Puma as it didn’t have the fit so we were going to fly the trials Wessex. There was a sense of urgency because at 13.00hrs the civil fire section was going on strike and the airfield would be closed; marooning us in Thurleigh.
My companion, ex 72 Sqn, went first whilst I chewed the rag with my old mate. He came back, we changed over, the LHS chap indicated that I had control and off we went. My enforced experience in the V Force ensured that flying a pseudo ILS was easy and there was no problem, as far as I could assess with a Puma at the DH it would stop quite happily.
I flew it back to the apron at Thurleigh and we landed at 12.55. The Puma was already burning and turning so I bid farewell to the safety pilot, jumped in the Puma and away we went back to Odiham.
It was a successful operation apart from two minor points:
1: The O/C trials unit had assumed that I was qualified on the Wessex, which I wasn’t. Having spent two tours in the Far East I had stacks of time on Whirlwinds but zero on the Wessex.
2: I had assumed the chap in the LHS was a pilot, which he wasn’t. He was a navigator or some other cave dweller with no idea about the Wessex and I had left him in the middle of one turning and burning in the middle of an airfield with no fire cover at lunchtime.
I had no trouble flying it; it was just two Siamesed Whirwinds. I think that the torquemeter’s needle, the Puma not having one in those days, may have ventured into unexplored territory.
My mate was dragged out of the dining room and rushed to his Wessex to shut it down as the occupant was having kittens over the radio. He telephoned to complain but after a very short time he realised what had really happened so he seemed to dry up somewhat.
I never did see or hear of MADGE in RAF service.
Last edited by Fareastdriver; 24th Jul 2013 at 13:16.
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Oil workers stranded after North Sea haar closes in
FOGBOUND workers are stuck on oil platforms as the North Sea haar has led to dozens of helicopters being grounded.
While Scotland basked in a heatwave some oil bears have missed family breaks due to being stranded.
Last week’s sizzling temperatures weren’t good news for companies and contractors as dozens of crew changes were postponed as the notorious haar shrouded oil installations.
Hundreds of workers were either stranded offshore on the beach as the world’s busiest heliport at Aberdeen Airport was forced to cancel dozens of flights.
And just as helicopters companies were trying to get back to normal thunderstorms and lightning strikes led to more flights being grounded.
One fed-up oil bear contacted Aberdeen Now to complain that some workers have missed out on family holidays abroad because of the backlog.
He said: “While everyone back home has been basking in the sunshine, oil workers have been stuck on the rigs because of fog hanging and not shifting in the North Sea.
“My mate was stuck offshore for an extra week and missed his family holiday abroad as have others.
“Some of the guys who have been working in the North Sea for years say they’ve seen nothing like it in 30 years.
While Scotland basked in a heatwave some oil bears have missed family breaks due to being stranded.
Last week’s sizzling temperatures weren’t good news for companies and contractors as dozens of crew changes were postponed as the notorious haar shrouded oil installations.
Hundreds of workers were either stranded offshore on the beach as the world’s busiest heliport at Aberdeen Airport was forced to cancel dozens of flights.
And just as helicopters companies were trying to get back to normal thunderstorms and lightning strikes led to more flights being grounded.
One fed-up oil bear contacted Aberdeen Now to complain that some workers have missed out on family holidays abroad because of the backlog.
He said: “While everyone back home has been basking in the sunshine, oil workers have been stuck on the rigs because of fog hanging and not shifting in the North Sea.
“My mate was stuck offshore for an extra week and missed his family holiday abroad as have others.
“Some of the guys who have been working in the North Sea for years say they’ve seen nothing like it in 30 years.