HOW IS LDP OF OIL RIG LANDING?
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HOW IS LDP OF OIL RIG LANDING?
FROM THE RFM LDP IS 50KNOT AND 300FT,I FEEL THE DISTANCE IS FAR FROM HELIDECK,SOMETIME I STILL CONFUSE WITH that LDP,WHO COULD EXPLAIN THAT?
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The LDP question
The RFM it must be remembered, is a certification document and is rarely, due to a singular lack of context, a handbook that relates to the real world and its problems.
The Cat A offshore procedures cannot possibly take into account the multitude of possible obstacle/turbulence situations that routinely change on a daily basis. They therefore have to be understood in this context or you simply turn around and go home anytime the text-book conditions are unavailable.
LDP is a point only you, the pilot conducting the landing, can nominate and is strictly the point at which you feel you can no longer make a safe go around and you are therefore committed to a landing.
The proximity of flare booms, crane barges, work-over barges, pipe-layers plus the known presence of troublesome turbulence will shape your decision. As the senior risk-manager on site you have the responsibility for deciding when the risk associated with a difficult approach is not worth the candle.
G.
The Cat A offshore procedures cannot possibly take into account the multitude of possible obstacle/turbulence situations that routinely change on a daily basis. They therefore have to be understood in this context or you simply turn around and go home anytime the text-book conditions are unavailable.
LDP is a point only you, the pilot conducting the landing, can nominate and is strictly the point at which you feel you can no longer make a safe go around and you are therefore committed to a landing.
The proximity of flare booms, crane barges, work-over barges, pipe-layers plus the known presence of troublesome turbulence will shape your decision. As the senior risk-manager on site you have the responsibility for deciding when the risk associated with a difficult approach is not worth the candle.
G.
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You know my flight manual says 50kts, 200ft. Not that 100ft really means all that much - but the S92 isn't exactly sprightly, nor does it have copious amounts of available tq and engine performance if you're on the -600ft a minute descent limit. And as Geoff says - the manual is 'theoretical' not 'real life.'
So if you have an engine failure after the RFM LDP figures but before you think you are really at LDP due to conditions and experience and then you crash because you try to go around - how are you placed legally?
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Crab
If everyone walks away from the wreck you did the right thing. If not then you will have to convince the board of enquiry that you used your 'best endeavours' to achieve a safe outcome.
We don't live in a PC1 world offshore.
Back in the 1970's the head of the CAA admitted that those early years saw commercial operations that were quasi-military. Cat A was required over land but as soon as you crossed the coast you were in indian territory. Not an awful lot has changed really save we now give the quasi military ops names like PC2e or PC2E.
G.
We don't live in a PC1 world offshore.
Back in the 1970's the head of the CAA admitted that those early years saw commercial operations that were quasi-military. Cat A was required over land but as soon as you crossed the coast you were in indian territory. Not an awful lot has changed really save we now give the quasi military ops names like PC2e or PC2E.
G.
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LDP/Committed
Rather than the Crab scenario I have seen many more incidents of pilots continuing to the deck in spite of being on a far too shallow approach and failing to make it when they had more than sufficient space and clearance to go around safely. (412 & 76 Simulators and not actual obviously)
Fully agree with Geoffers!
Trog.
Fully agree with Geoffers!
Trog.
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PC2 e = PC2 with exposure
PC2 E = PC2 'Enhanced'
PC2 E = PC2 'Enhanced'
Exposure is a concept included in PC2 operations and is not defined as you mentioned.
By the way, military ops are far from any PC2e concept that require the same level of safety of PC1 but without the the extra informations such distances and gradients.
Please before teaching, check if you are on the right page.
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Just look at us squabbling over the terminology ...... no wonder the customer looks at us in bemusement ...... Why not add more bumpf that few will bother to understand ..... PC2DLE !!! (Defined Limited Exposure) ....... as pilots its simply fly the profile that the boss describes in his Ops Manual .........
Last edited by tistisnot; 14th Oct 2015 at 02:47.
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Margins
My apologies to anyone who mistook my post for an attempt to lecture on this complex subject. It was meant as a flippant and amusing comment but one that had an underlying truth, offshore CAT in the 1970's was anything but 'kosher'. I have to tell you that in some parts of the world it's still like that.
What of PC2e & E - Back in the days when these concepts were in their infancy (the 1990's) the dialogue we used in correspondence was a shorthand that made reference to the offshore requirements in so-called 'hostile environments' (e.g. The North Sea) - this was PC2 but this version of PC2 was only accepted by the regulator (then the UK CAA) on the basis of an acceptable exposure time. (This was calculated by experts using probability theory I believe). Hence PC2e
The version of PC2 embraced by JAROPS 3 NPA38 (around 2004 I recall) and was intended to make up for the fact that JAR had recognised that their goal of universal PC1 was unattainable in the offshore environment and a better version of 'exposure' was required. The version required a statement of engine reliability (less than one failure in every 100,000 flight hours) by the airframe manufacturer, bolstered by HUMS or something equivalent. To differentiate we use the acronym PC2E.
The advent of EASA meant that things may have taken a different path but I haven't been following that subject area very closely as offshore (Europe) is not my main focus.
G
PS - If we are to compare CAT with Mil Ops then I think it's fair to comment that when you have to manipulate data and create algorithms and invent new performance/operating categories to allow folk to go about their daily tasks offshore then we can comment that the regulators are being creative. If it is something less than absolute PC1 then Joe Public is entitled to call those ops 'quasi military' - i.e. they adopt a regime appropriate to the essential nature of the task whilst maximising safety.
What of PC2e & E - Back in the days when these concepts were in their infancy (the 1990's) the dialogue we used in correspondence was a shorthand that made reference to the offshore requirements in so-called 'hostile environments' (e.g. The North Sea) - this was PC2 but this version of PC2 was only accepted by the regulator (then the UK CAA) on the basis of an acceptable exposure time. (This was calculated by experts using probability theory I believe). Hence PC2e
The version of PC2 embraced by JAROPS 3 NPA38 (around 2004 I recall) and was intended to make up for the fact that JAR had recognised that their goal of universal PC1 was unattainable in the offshore environment and a better version of 'exposure' was required. The version required a statement of engine reliability (less than one failure in every 100,000 flight hours) by the airframe manufacturer, bolstered by HUMS or something equivalent. To differentiate we use the acronym PC2E.
The advent of EASA meant that things may have taken a different path but I haven't been following that subject area very closely as offshore (Europe) is not my main focus.
G
PS - If we are to compare CAT with Mil Ops then I think it's fair to comment that when you have to manipulate data and create algorithms and invent new performance/operating categories to allow folk to go about their daily tasks offshore then we can comment that the regulators are being creative. If it is something less than absolute PC1 then Joe Public is entitled to call those ops 'quasi military' - i.e. they adopt a regime appropriate to the essential nature of the task whilst maximising safety.
Last edited by Geoffersincornwall; 15th Oct 2015 at 09:12. Reason: clarification & PS
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LDP
Hi All,
I guess it really boils down to the type you are flying.
I have had an engine failure after LDP or as we called it then, "Committed" on an S-61N to an offshore platform with 22 PAX on-board @ 32C with about 5 knots of wind and it was a non-event. My experience with the AS332L2 is only in the SIM but the results @ the Delta Speed (LDP) were very similar to the S61N in real life.
Now if you use the accepted numbers for the S76C++ or S92A, I believe that you would not end your day with a smile on your face. I may be wrong as it really depends on who is flying the approach and what there own definition is.
Just my two centavos worth.
I guess it really boils down to the type you are flying.
I have had an engine failure after LDP or as we called it then, "Committed" on an S-61N to an offshore platform with 22 PAX on-board @ 32C with about 5 knots of wind and it was a non-event. My experience with the AS332L2 is only in the SIM but the results @ the Delta Speed (LDP) were very similar to the S61N in real life.
Now if you use the accepted numbers for the S76C++ or S92A, I believe that you would not end your day with a smile on your face. I may be wrong as it really depends on who is flying the approach and what there own definition is.
Just my two centavos worth.
the accepted numbers for the S76C++ or S92A
The 92 has way better power margins than the good old 61 operating at 20500 lbs, or the modern day 225 for that matter.
Finally a Class 2 approach i.e. an offshore approach, does not have an LDP only a DPBL (Defined Point Before Landing).
Airbus Helicopters has a neat little APP called PC2 DLE you can find in the APP Store.
Hours of fun for the whole family.
Cheers
Albatross
PS
offshoreigor - hope all is well with you. Long way from Kigali are we not.
Hours of fun for the whole family.
Cheers
Albatross
PS
offshoreigor - hope all is well with you. Long way from Kigali are we not.
