The Piper PA commander, was being flown by former commercial airline pilot Steve Carr, 55, and Mid Wales airport manager Bob Jones, 60 when it crashed on January 18.

Mr Carr, from Ruthin, was carrying out the flight to re-familiarise himself with the Piper PA, which he had not flown since November 1998 when the accident happened.

The report from the Air Accidents Investigation Branch (AAIB) said the pair would have been aware of the proximity of Long Mountain, but they “may have thought they had cleared the high ground.”

The report said it was unlikely that the pilots would have deliberately entered the cloud “but may have misjudged their height above it and inadvertently entered the top of the cloud, which was obscuring the trees”.

The aircraft struck the top of the trees on the upper slope of Long Mountain near Mid Wales airport, which had been founded by Mr Jones.

The Piper PA took off from Welshpool and was due to land back there.