The couple were said to be unaware of how close they came to crashing, but the near miss is being investigated by Britain's Department of Transport.
According to The Mail on Sunday , the Air Accidents Investigation Branch has categorised the episode - which occurred on May 3 - as a "serious incident", which it defines as "involving circumstances indicating that an accident nearly occurred".
The report also reveals flying conditions that night included "low cloud base, poor visibility and rain".
Despite this, the pilot went ahead and prepared to land on Sir Paul's helipad, which is in the corner of a field encircled by woodland.
It added: "While manoeuvring, the commander became disorientated and the helicopter descended towards tops of trees in the forested area to the south and west of the landing site."
The pilot then "executed a go-around" or aborted landing.
Peter Norton, chief executive of the British Helicopter Association, said: "He [the pilot] was going to land and realised he wasn't in control of the aircraft because of the weather conditions and visibility; he pulled in lots of power to climb away and correct the aircraft to its proper flightpath and missed whatever it was by two feet."
Paul's spokesman said: "Paul has been spoken to. It has been put to him, everything. It's a no comment."
- Bang! Showbiz