A Bell 212 helicopter (G-BARJ) was on a winching training flight in the Brent Oilfield area located in the North Sea 116 miles (186 kilometres) north-east of Lerwick, Shetland Islands, Scotland. Onboard the aircraft were one pilot and one winch operator. This to remain below the sing engine hover weight.
The Bell 212, G-BARJ, subject of this blog (© Peter Nicholson)
Conditions were good for a training flight, although the wind was less than 10 knots the sea state (according to the Douglas Sea Scale) was rough to very rough with waves 4 - 5 meters high, with some higher waves rolling through occasionally. After performing four practice lifts the pilot requested to perform some practice winching over the deck over the Brent Charlie stand-by vessel the “Huddersfield Town”. The winching area on the stern of the ship had a diameter of 20 feet and was painted yellow. A guard rail of 3 ½ feet high provided fall protection for the ship’s crew.
Brent Charlie stand-by vessel the “Huddersfield Town
The starboard cabin door of the helicopter was locked open with the winch operator sitting in the door opening. He lowered the winch (with a ballast weight) to the deck while the aircraft was in a steady hover for 1-2 minutes at 20-30 feet over the deck of the ship while maintaining the aircraft over the centre of the winching area. All was well until a swell lifted the stern of the ship and the winch cable coiled up on the deck, to correct this the winch operator started to winch in the cable when the stern of the ship slid sideways of a wave and the winch cable and ballast weight got trapped in the ship’s railing. This pulled the winch cable taut and with that pulled the helicopter to the right and caused it to pitch down, which the pilot attempted to correct with full left cyclic. However, the nose down attitude could not be corrected and the aircraft nose-dived into the sea at an altitude approximately 45° nose down. The elapsed time between the cable getting trapped and the aircraft in the water was estimated to be 3-4 seconds, so quick that neither crew had the time to operate the cable cutter switch.
Upon hitting the water the helicopter immediately inverted with the flotation equipment only partly inflating. Both crew members scrambled to the surface after releasing their harnesses. Both indicated afterwards being disorientated underwater and struggling to get out of the wreckage. The pilot received injuries to his left knee, forehead and cuts and bruises over his body. The winch operator only received minor cuts and bruises. Both men were rescued by the Huddersfield Town and made full recoveries.
The Bell 211
Specifications of the Bell 212;
Crew: 1 (two for IFR operation)
Capacity: 14 passengers
Length: 57 ft 1.68 in (17.4163 m)
Height: 12 ft 6.83 in (3.8311 m)
Empty weight: 6,529 lb (2,962 kg)
Max takeoff weight: 11,200 lb (5,080 kg)
Powerplant: 1 × Pratt & Whitney Canada PT6T-3 or -3B turboshaft engine, 1,800 shp (1,300 kW) (TwinPac)
Main rotor diameter: 48 ft 0 in (14.63 m)
Main rotor area: 1,809.5 sq ft (168.11 m2)
Cruise speed: 100 kn (120 mph, 190 km/h)
Vmo: 120 kn (140 mph, 220 km/h)
Range: 237 nmi (273 mi, 439 km)
Service ceiling: 17,400 ft (5,300 m)
Rate of climb: 1,745 ft/min (8.86 m/s)
Disk loading: 6.19 lb/sq ft (30.2 kg/m2)