TWO RAF AIRCRAFT came within 400ft of each other during training flights just south of Inverness, according to a report by the UK Airprox Board.
The incident in February involved one of two Tornado jets from RAF Lossiemouth that was climbing rapidly into airspace already occupied of a pair of Tucano aircraft which were en-route to the Moray base.
In their report on the incident HQ Air Command concluded that the fitting of a Collision Avoidance System (TCAS) on the Tucano aircraft was a major factor in avoiding an accident.
A Radar Controller at Inverness Airport told the investigation that he had been working the Tucano aircraft, which he believed he had pre-noted to RAF Lossiemouth. As a Tucano passed 4nm south of Inverness there was a call from Lossiemouth requesting traffic information on it as they had a pair of Tornado GR4’s flying in the opposite direction at a range of 12 miles and climbing.
The Tornado controller at RAF Lossiemouth issued a “stop climb” order to the Tornado pilots and believed this had been acknowledged when he heard the pilot broadcast his callsign.
However, investigators concluded that the Tornado pilot had not heard the stop climb instruction – and had not taken “adequate action” to ensure sufficient separation between the aircraft, resulting in a late sighting.
Commenting on the ‘Category B’ incident, HQ Air Command concluded that “none of the Tornado crew members heard the instruction to stop climb before the level of the Tucano” – although there was “clear evidence” that the aircraft did transmit the formation callsign immediately after the instruction.
The report added: “The controller interpreted the transmission of the formation callsign as acknowledgement of the instruction even though a full read-back should have been transmitted by the Tornados.
“This highlights the importance of adherence to standard phraseology – it is usually borne out of bitter experience – and the importance of insisting that clearances be read back in full.”
The report author said that the most effective barrier to disaster in this instance was the Collision Avoidance System fitted to RAF Tucano aircraft.
He said: “The most effective barrier in this incident was the Tucano TCAS, which provided the Tucano crew with enough situation awareness to acquire the Tornados visually and thus negate any chance of the situation degrading further.”