"But we did it successfully - their main injuries were knees and ankles and were very serious."
He said they were both conscious "but the worse for wear".
"To free the motor and dash was quite difficult. There is not a lot of room in the plane and when it was concertinaed there was even less, so it was quite difficult to do without hurting the patients.
"It took us an hour, which to us is a long time, but that's the way it had to be."
Lowe Corporation Rescue Helicopter chief pilot Charlie Beetham said the plane was removed from around the men and a strop tied to a tractor, to secure the plane should it shift once the engine was removed.
He said he knew the pilot, "which was a bit of a shock".
"When they are fellow aviators it makes it a bit more personal. He is a very well-known and respected pilot."
Both men, who are believed to be in their 60s, suffered suspected fractures to their limbs and "other injuries", St John spokesman Brendon Hutchinson said. They were treated in the plane and lifted straight into the helicopter.
It was not known why the men were landing at the start of the day on Mr Langslow's farm, where there were no apparent fertiliser facilities.
An industry commentator said it was possible they were returning from a job that had to be abandoned because of the weather. There was fog in some parts of the district at the time of the crash.
A Civil Aviation Authority spokesman said the prevailing weather "and the contributing factors of the accident sequence" would be investigated.
"It could be up to 12 months before a final report is available."