Saturday, August 23, 2014

Report reveals near miss between helicopter and jet

A helicopter and a RAF jet came close to a “potentially disastrous” crash above a Scottish island, the report of an official probe released today has revealed. 

Investigators said the incident highlighted the need of the previously cancelled Tornado Collision Warning System which is now planned to be fitted to the fleet this year.

Earlier this year it was revealed that a warning system which could have prevented a fatal crash between two Tornado jets in Scotland in 2012 was cancelled twelve years after a commitment to its implementation had first been made by defence chiefs.
 
Flight Lieutenant Adam Sanders, Squadron Leader Samuel Bailey and Flight Lieutenant Hywel Poole were killed when the two Tornado GR4s, based at RAF Lossiemouth, collided over the Moray Firth.

It was revealed in December, in a written answer from Tory defence equipment minister Philip Dunne, that a collision warning system costing around £60 million for the fighter jets was considered four years before the fatal crash and that the Government decided in January 2012, six months before the crash, to tender for a different system developed by BAE which was £6 million cheaper.


But Angus Robertson, the SNP MP for Moray, revealed that a Freedom of Information request had disclosed that the then Conservative Secretary of State for Defence, Dr Liam Fox, cancelled its installation a full twelve years after a commitment had been made to do so against the advice of the Military Aviation Authority. The MAA had warned that, without installation of the system, they would not be able to certify the risk of collision as being acceptable

Near miss

The latest near miss incident involving a Tornado jet to come before the UK Airpox Board happened on April 10 about 1.5 miles north west of the Hebridean island of Gigha
The Tornado was conducting a low-level tactical formation sortie below the 4000 feet cloud base. As he did a right turn he noticed the helicopter about 500 metres away.

The Tornado was manoeuvred hard into the turn and descended to avoid the Eurocopter AS355. The helicopter was flying straight-and-level and was not seen to manoeuvre.
The Tornado pilot assessed the risk of collision as ‘medium.’

The helicopter pilot was flying at about 1000ft when he saw a grey Tornado to his left, coming from the north, just as it broke away to its right and flew behind him.

He assessed the risk of collision as “potentially disastrous.”

The UK Airprox Board, which investigates near misses, heard that neither aircraft was fitted with an Airborne Collision Avoidance System (ACAS) or True Air Speed (TAS) nor were the pilots in receipt of an Air Traffic Service (ATS).

“The only effective barrier remaining was lookout. On this occasion it appears that the Tornado pilot was the first to visually acquire the other aircraft (albeit late) and immediately took action to resolve the conflict and increase separation - a manoeuvre that highlighted his aircraft to the helicopter pilot. Once again this incident serves as a reminder that effective lookout is crucial....” HQ Air Command told the investigation.

Risk of collision

The Board said the cause of the airprox was a late sighting by both pilots and assessed the risk of collision as B - the second highest rating where safety was not assured.

“The Board first assessed the actions of the pilots involved and quickly determined that the cause of the Airprox had been a late sighting by both pilots,” it said.

“Not being within ATS coverage, and with neither aircraft having electronic aids to collision avoidance, both pilots were relying exclusively on ‘see-and-avoid’.

“The Tornado pilot did not see the helicopter until it passed through his field of view during his right-hand turn, and the AS355 pilot did not see the Tornado until its pilot broke away from him.

“The Board postulated that the reasons for the late sightings could have been that the Tornado pilot might have been concentrating his lookout on regaining formation integrity as he manoeuvred, whilst the AS355 pilot might have been in a state of low-arousal given his apparently benign flight conditions and low complexity transit task.

“This was not to criticize either of the pilots but rather to emphasise the importance of effective all-round lookout at all times. In addition, members noted that, weather and task permitting, by remaining above 2000ft, airspace users would avoid the majority of military low-level fast-jet traffic and they heartily encouraged those conducting simple transits to consider this as an option.

“Given the difficulties of seeing a grey camouflaged Tornado against the sea and a relatively slow-moving helicopter on a constant bearing, the Board opined that an effective mitigation would also have been provided if one or both aircraft had been fitted with a TAS or ACAS; in this respect, the Board was heartened that the previously cancelled Tornado Collision Warning System (CWS) was now planned for introduction to the Tornado fleet during the current fiscal year.

“The Board felt that the conditions and dynamics of the event were pertinent in assessing its risk. Although the Tornado pilot had reacted correctly to the presence of the helicopter, his closing speed and late sighting reduced his ability to achieve an appreciable increase in separation.

“The Board considered that neither pilot had been in a position to achieve timely and effective collision avoidance, and that safety margins had been much reduced below the norm.”

- Source:  http://www.scotsman.com

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