Flying Lawyer
18th Jun 2004, 08:47
http://news.bbc.co.uk/olmedia/1650000/images/_1652970_copter300.jpg
An unnoticed problem on a North Sea drilling ship led to an on-deck helicopter toppling over while its rotors still were running, an official accident report said today.
Unknown to both the ship's and helicopter's crews, the dynamic positioning system of the West Navion drilling ship reverted to manual heading control, and the vessel started drifting slowly to the right.
This led to the Super Puma helicopter, which was refuelling after a journey from Aberdeen, toppling over to its right, the report from the Air Accidents Investigation Branch (AAIB) said.
The 35-year-old co-pilot – who was on the helideck checking the helicopter – suffered severe leg injuries from flying debris as the main rotors broke up on impact with the deck.
The 37-year-old commander of the helicopter, who had remained on board, managed to escape, with difficulty, through the left pilot's door in the incident, which happened 80 miles west of Shetland on November 10, 2001.
The helicopter crew had flown 12 of the ship's crew in from Aberdeen and these passengers had disembarked before the incident.
The toppling-over occurred seven minutes after the ship started to drift.
No-one on the West Navion's bridge was initially aware of the situation, and the helicopter commander was not informed of the ship's change of alert status.
The AAIB report of the November 2001 accident concluded: "The lack of procedures on the ship to transmit the change in the alert status to the crew of the helicopter and of any specified procedures available to flight crews concerning action to be taken if control of the ship is lost or degraded whilst on the helideck, denied the pilot an appropriate course of action to ensure the safety of the helicopter."
The AAIB has made the following safety recommendations:
(1) That the CAA should require Operators conducting offshore operations to publish crosswind limitations for helicopters when operating to, and when positioned on, helidecks, incorporating these limits into their company Operations Manuals.
(2) That the CAA require offshore operators to review their landing procedures such that, after landing on moving helidecks, the helicopter's roll attitude, relative to the helideck, is neutral.
(3) That UKOOA revise their Guidelines for the Management of Offshore Helideck Operations to include a requirement for significant changes in environmental conditions, particularly wind speed and relative wind direction, to be communicated the pilot of a helicopter when parked, with rotors turning, on a helideck.
(4) That UKOOA should include in its Guidelines for the Management of Offshore Operations a requirement that, following an accident or incident (regardless of whether or not it involved a helicopter at the time), operators of vessels, Mobile Offshore Drilling Units (MODUs) and fixed installations should consider in their subsequent installation safety investigations the potential safety implications for helicopter operations on helidecks.
An unnoticed problem on a North Sea drilling ship led to an on-deck helicopter toppling over while its rotors still were running, an official accident report said today.
Unknown to both the ship's and helicopter's crews, the dynamic positioning system of the West Navion drilling ship reverted to manual heading control, and the vessel started drifting slowly to the right.
This led to the Super Puma helicopter, which was refuelling after a journey from Aberdeen, toppling over to its right, the report from the Air Accidents Investigation Branch (AAIB) said.
The 35-year-old co-pilot – who was on the helideck checking the helicopter – suffered severe leg injuries from flying debris as the main rotors broke up on impact with the deck.
The 37-year-old commander of the helicopter, who had remained on board, managed to escape, with difficulty, through the left pilot's door in the incident, which happened 80 miles west of Shetland on November 10, 2001.
The helicopter crew had flown 12 of the ship's crew in from Aberdeen and these passengers had disembarked before the incident.
The toppling-over occurred seven minutes after the ship started to drift.
No-one on the West Navion's bridge was initially aware of the situation, and the helicopter commander was not informed of the ship's change of alert status.
The AAIB report of the November 2001 accident concluded: "The lack of procedures on the ship to transmit the change in the alert status to the crew of the helicopter and of any specified procedures available to flight crews concerning action to be taken if control of the ship is lost or degraded whilst on the helideck, denied the pilot an appropriate course of action to ensure the safety of the helicopter."
The AAIB has made the following safety recommendations:
(1) That the CAA should require Operators conducting offshore operations to publish crosswind limitations for helicopters when operating to, and when positioned on, helidecks, incorporating these limits into their company Operations Manuals.
(2) That the CAA require offshore operators to review their landing procedures such that, after landing on moving helidecks, the helicopter's roll attitude, relative to the helideck, is neutral.
(3) That UKOOA revise their Guidelines for the Management of Offshore Helideck Operations to include a requirement for significant changes in environmental conditions, particularly wind speed and relative wind direction, to be communicated the pilot of a helicopter when parked, with rotors turning, on a helideck.
(4) That UKOOA should include in its Guidelines for the Management of Offshore Operations a requirement that, following an accident or incident (regardless of whether or not it involved a helicopter at the time), operators of vessels, Mobile Offshore Drilling Units (MODUs) and fixed installations should consider in their subsequent installation safety investigations the potential safety implications for helicopter operations on helidecks.