Wreckage found in far north Queensland waters has been confirmed to be that of an Royal Australian Air Force plane that crashed more than 70 years ago, killing all 11 people on board.

The wreckage of RAAF Number 11 Squadron Catalina A24-25, which crashed in February 1943, was found 56km south of Cairns by a diver in 2013, but weather and planning challenges delayed the final dives to complete the investigation.

An engine mount from Catalina 24-25. The aircraft was discovered in waters off Cairns in far North Queensland. Credit:Kevin Coombs

"The discovery of this Number 11 Squadron Catalina is important for the Air Force and our ongoing commitment to account for our missing personnel from past conflicts; currently 3124 from the Second World War and 18 from Korea," Chief of Air Force, Air Marshal Leo Davies said.

"It is even more important for the families to finally have some closure in knowing the resting place of the aircraft and their loved ones after such a long time."