The plane crashed into the rugged mountainside near the Apex ski resort, about 25 kilometres west of Penticton. (CBC)

The RCMP have squelched speculation that a small plane that went down in a crash-prone area of southern B.C., killing four men, may have been involved in illegal activity.

A published report in Vancouver following the Aug. 17 crash suggested the doomed plane might have been ferrying drugs from the Okanagan to Vancouver Island.

A check of the crash site on Apex Mountain turned up no trace of contraband, RCMP said in a news release.

The Piper Comanche crashed shortly after takeoff from Penticton on a flight to Victoria.

High crash area

The area is notoriously tricky to fly through, said local flight school operator Mark Holmes, who runs Southern Skies Aviation in Penticton.

He said an optical illusion can make it hard for pilots to clear the top of Apex Mountain.

"They quickly get surrounded by terrain and are unable to outclimb it and are in fact unable to turn around," Holmes said, adding he knows of at least 12 accidents in the same area.

The plane hit the ground at an almost vertical angle, Transportation Safety Board spokesman Bill Yearwood said.

The attitude of the crashed plane could suggest that pilot Rama Tello tried to pull his plane into too sharp a climb, which can force an aircraft to lose lift and suddenly dive.

The TSB is still investigating the latest crash and a report is not expected for several months.

The four men — Tello, his brother and two of their friends — were all from the Kelowna area.