1983 British Airways Sikorsky S-61 crash

1983 British Airways Sikorsky S-61 crash

A ditched British Airways Sikorsky S-61N helicopter similar to the aircraft involved in the accident.
Accident summary
Date 16 July 1983
Summary Pilot error in poor visibility
Site Sea near St Mary's Aerodrome,
Isles of Scilly
49°55.4′N 6°14.9′W / 49.9233°N 6.2483°WCoordinates: 49°55.4′N 6°14.9′W / 49.9233°N 6.2483°W
Passengers 23
Crew 3
Injuries (non-fatal) ...
Fatalities 20
Survivors 6
Aircraft type Sikorsky S-61N
Operator British Airways Helicopters
Registration G-BEON
Flight origin Penzance Heliport
Destination St Mary's Aerodrome, Isles of Scilly

On 16 July 1983, British Airways Helicopters' commercial Sikorsky S-61 helicopter Oscar November (G-BEON) crashed in the southern Celtic Sea, in the Atlantic Ocean, when en route from Penzance to the St Mary's, Isles of Scilly in thick fog. Only six of the 26 on board survived. It sparked a review of helicopter safety and was the worst civilian helicopter disaster in the UK until 1986, when Boeing 234LR Chinook helicopter G-BWFC crashed in the North Sea.

Background

Owned by British Airways Helicopters, the Sikorsky S-61N registered G-BEON operated between Aberdeen and the oil platforms of the North Sea.

On 22 June 1983, Oscar November received its last annual certificate of airworthiness.

On 24 June 1983, it was being used as a replacement helicopter, operating the British Airways Helicopters service between Penzance and the Isles of Scilly. The helicopter which would normally run the service, ever since its purchase in 1974, was in for repairs.

Incident

Oscar November left Penzance on its scheduled 12:40 pm service to the Isles of Scilly. It was flying at 250 feet (80 m) over the Celtic Sea, due to poor visibility. Then, at 12:58 pm, air traffic control on St Mary's lost contact with the helicopter, before it had the chance to send a Mayday signal or to ditch under power. It had crashed nose-first into the sea and sunk immediately, only 2.5 miles (4.0 km) from St Mary's Airport. The six survivors were unable to don lifejackets in time, but were able to float for 30 minutes before St Mary's lifeboat RNLB Robert Edgar (ON 1073) attended the scene.

The survivors were: two children, both of whom were orphaned by the incident; the two pilots, Dominic Lawlor and Neil Charleton; and the only two Scillonians on board, Lucille Langley-Williams and Megan Smith. There were twenty fatalities.

The helicopter did not carry a black box, as it had been found that the vibrations from helicopter flight rendered conventional black box recordings unreliable. The only record of the flight was from the pilot's log, documents carried in a pouch in the cabin.

Survivor's account

Langley-Williams told The Times (20 July 1983, p. 28 & 18 July 1983, p. 26): "It was very quick. I bumped forwards and hit my head on the seat in front." She asked Smith, "'What the hell is going on?'" The response was one word, by which time the passengers were chest-deep in seawater. "I closed my mouth and took a deep breath and by then I was under water." The seat had twisted on impact, tightening the seatbelt. "I realised I had not got an awful lot of breath left." She released the belt, opened the door and floated to the surface.

On the surface, she found the five other survivors. Shortly after, the two maroons signalling the launch of St Mary's Lifeboat could be heard. "We were just chatting about what would happen and I said the boat was on its way." Rescue helicopters from RNAS Culdrose could not see the survivors through the thick mist. "It was the most wonderful moment in my life to see the coxswain's face as he reached down over the side of the lifeboat."

The coxswain of the lifeboat was Matt Lethbridge.

Recovery

The fuselage of Oscar November was located by its locator beacon and was recovered from 200 ft (60 m) below the surface primarily by Royal Navy divers of Naval Party 1007 aboard the MV Seaforth Clansman (Chartered to the Royal Navy as a deep sea saturation diving vessel) at 1 p.m. on 19 July. The MV Seaforth Clansman, along with Penlee lifeboat RNLB Mabel Alice (ON 1085), had the duty of returning 17 bodies to shore.

The aircraft had lost its nose-cone and sponsons (wheel housing and floatation device). The starboard sponson was damaged but retained its capacity to float; the port was undamaged and failed to float. Three of the five main blades had been sheared off, along with the rear rotor blades. The cabin was badly damaged. The port-side escape windows were missing.

Investigation

The fuselage was taken to the Government's Air Accidents Investigation Branch at Farnborough, Hampshire.

Initially there was speculation that the helicopter could have flown into a flock of seagulls after mutilated bird corpses were found near the scene. However, Islanders found more dead seabirds on the shore, without mutilations. To add to the evidence against, the grille that prevents seabirds entering the engine was found intact.

Cause

A report investigating the incident was concluded twenty months later, in February 1985, finding the cause to be 'pilot error'. The official report concluded that the accident was caused by the pilot not observing and correcting an unintentional descent before the helicopter collided with the sea during an attempt to fly at 250 feet using visual clues in poor and deceptive visibility over a calm sea.[1] The report also added that the following were contributory factors:[1]

Safety recommendations

The Accident Investigation Branch made eight recommendations:[2]

Legacy

The main recommendation from the report was for an audible height warning on passenger helicopters operating off-shore and for the altimeter to be moved nearer to the pilot's 'head-up field of vision'. Ground proximity warning systems were made compulsory on passenger planes in 1977. It was also recommended that:

The Sunday Times (24 March 1985) reported that of eight recommendations made in the report, seven were accepted by the CAA after the report, five had been suggested before the crash and three were already in force on other passenger aircraft operations at the time.

See also

References

  1. ↑ 1.0 1.1 AAIB 1985, page 39
  2. ↑ AAIB 1985, page 40

External links