A US Air Force jet performing training exercises at Casement Aerodrome almost collided with a passenger aircraft over Dublin Airport, the Air Accident Investigation Unit has found.
The US Learjet trainer came within 1.5 miles and 400 ft of an Air Luxor charter flight, constituting "a serious risk of collision", according to the air authority's latest bulletin.
The AAIU said "the incident [in 1988] was due to poor navigation on the part of the military aircraft and the non-compliance with ATC [air traffic control] clearance".
It noted that the jet's captain had indicated he was aware of the approach procedure to the Air Corps aerodrome at Baldonnel in west Dublin but subsequent events showed this was not the case.
A spokesman for the Army said US Air Force jets based in Europe used Baldonnel occasionally for training exercises, with the approval of the Department of Foreign Affairs.
According to the AAIU, the incident occurred on November 7th, 1988, while the jet was on a weekend visit from Ramstein in Germany.
The AAIU bulletin also details a "serious incident" involving a Garda helicopter deployed to airborne security for the motorcade of Mrs Hillary Clinton, the wife of the US president, on a visit to the west last summer.
During the night-time operation, nine miles north of Ennis, Co Clare, the helicopter inadvertently entered cloud. The Air Corps pilot caused the helicopter to deviate from its normal course. It climbed to 1,700 ft, where it levelled off. The normal operating height was between 800 and 1,000 feet.
In its recommendations, the AAIU said the Air Corps should suspend night operations involving the Garda helicopter in rural areas "with immediate effect" until an effective programme of extra night flying is completed by pilots. The Army spokesman said all recommendations would be complied with.
In a further incident reported by the AAIU, the pilot of an aircraft with 50 people on board slumped unconscious at the flight controls as it approached Dublin Airport.
The co-pilot of the daily passenger service between Vienna and Dublin had to land the aircraft after declaring a medical emergency and requesting priority clearance for landing.
The commander regained consciousness after the aircraft had landed and was removed to Beaumont Hospital for examination. He has been removed from flying duties since the incident occurred on July 22nd last, pending the outcome of a detailed medical investigation in his home country of Austria.
The latest reports of the Air Accident Investigation Unit can be found on its website: www.irlgov.ie/tec/aaiu
