On 16 July 1983, British Airways’ commercial Sikorsky S-61 helicopter Oscar November (G-BEON) crashed in the southern Celtic Sea 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 a Chinook helicopter crashed in the North Sea.

Background

Owned by British Airways, the Sikorsky 61 Oscar November operated between Aberdeen and the oil platforms of the North Sea.

On 22 June 1983, Oscar November received it’s last annual certificate of airworthiness.

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

Incident

Oscar November left Penzance on it’s scheduled 12.40 pm service to the Isles of Scilly. It was flying at 250 feet 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 sank immediately, only two and a half miles 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 attended the scene.

The survivors were: two children, both of whom were orphaned by the incident; the two pilots, Dominic Lawlor and Neil Charlton; and the only two Scillonians onboard, Mrs Lucille Langley-Williams and Mrs 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 render 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

Mrs 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 Mrs 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 release the belt, opened the door and floated to the surface.

On the surface, the 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 it’s 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 fusilage of Oscar November was recovered 200-ft below the surface by the RNXS salvage tug HMS Seaforth Clansman at 1 pm on 19 July. The Seaforth Clansman, along with Penlee Lifeboat RNLB Mabel Alice, had the duty of returning 17 bodies to shore. She was located by her cator beacon.

Some of the passengers found inside still had their seatbelts on, indicating the lack of fore-warning of the crash.

The craft lost it’s nose-cone and sponsons (wheel housing and floatation device). The starboard sponson was damaged but retained it’s 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.

Safety issues

The Times (19 July 1983, p. 1) reported that one of their freelance journalists, who had travelled to the isles on the helicopter service four days before the disaster, was interviewed by BA boardroom officials. She raised the following issues that she was concerned about:

Cause

The fusilage was taken to the Government’s accident investigation branch, the Royal Aircraft Establishment 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.

A report investigating the incident was concluded twenty months later, in February 1985, finding the cause to be ‘pilot error’. According to Malcolm Bruce in The Times (20 March 1985): “the pilot, Dominic Lawlor, was operating visual and instruments on approach then switched to visual only, became disorientated and descended into the water without realising he was doing so.” The pilot was flying within BA regulations. He misjudged the altitude because of a fog bank and crashed into the sea, bouncing along the water, removing the floor and sponsons.

The conclusion of the report states:

The accident was caused by the commander not observing and correcting an unintentional descent before the helicopter collided with the surface, whilst he was attempting to fly at 250 ft by external visual reference only in conditions of poor and deceptive visibility over a calm sea. Contributory factors were: inadequate flight instrument monitoring; a combination of VFR weather minima which were unsuited to visual flight and insufficiently detailed company operating proceduresl and the lack of an audio height warning equipment.

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 places 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.

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