Details have emerged of how a Boeing 757 with over 200 people on board came across a groundkeeper on a ride-on lawn mower trundling down the runway at Dublin Airport in the middle of the night.

The groundskeeper was not aware of the aircraft until he heard the roar of its engines racing down the runway behind him and the wings of the aircraft passed over him.

Today the Irish Air Accident Investigation Unit published its final report into the incident, which could have had catastrophic consequences.

The aircraft with eight crew and 198 passengers was landing in Dublin on a chartered flight from Sharm el Sheikh in Egypt just before 3am on 29 May last.

Visibility was poor when the plane had landed on Runway 10 and was decelerating when the cockpit crew noticed something on the right-hand side of the runway.

'I could have sworn I saw a man riding a lawn mower,' the co-pilot is reported as saying.

The matter was immediately reported to the Air Movement Controller in Dublin Airport who replied: 'I don't believe it. They told me they were clear of the runway.'

The groundskeeper got off the runway seconds after the aircraft passed him. The plane parked as planned and everyone disembarked safely. No one was injured.

The AAIU report states that there had been problems cutting the grass due to bad weather and a number of pilots had reported that lights were obstructed by tall grass.

The Dublin Airport Authority decided that cutting the grass was a priority and that was being done on the night in question.

However, grass-cutting operations were halted due to poor visibility. While two of the three grass-cutting machines left the area, there was a misunderstanding with the driver of the third vehicle.

He did not leave the area immediately. Instead he was proceeding down the runway to take a slip road when the aircraft landed.

In their final report, the AAIU states that the ride-on mower did not have adequate radio communications or lighting equipment. The tractor mower has since been replaced.

The final report also states that there were deficiencies in one airport regulation and in training of DAA personnel involved in this incident.

It recommends the DAA review their training programmes.