ST. JOHN'S, N.L. -- The RCMP say the daunting size of the remote Labrador lake where a float plane plane crashed July 15 has complicated an ongoing underwater search for four missing men and the aircraft that was carrying them.

GPS co-ordinates of the downed de Havilland DHC-2 Beaver plane, owned by Quebec airline Air Saguenay, were recorded when Maritime Forces Atlantic left the scene July 16, Cpl. Jolene Garland says.

But since then, the RCMP believes, high winds and heavy rain have caused the plane to drift.

Divers have been searching Mistastin Lake, about 100 kilometres southwest of Nain, since last weekend, but so far only small pieces of debris from the plane have been found.

Garland said Wednesday that the challenging search has become almost like searching for a needle in a haystack as divers grapple with the lake's 16-kilometre length and extreme depth.

She said the search teams intend to investigate "objects of interest" in the lake with divers and with a remotely operated vehicle that can reach greater depths.

Seven men, including the pilot, were onboard the float plane that left Three Rivers Lodge in Labrador to fish on Mistastin Lake.

Three bodies have been recovered and four men are still missing.

The cause of the crash is still unknown. The Transportation Safety Board of Canada says investigators will visit the site to inspect the plane after it has been located and removed from the water.