The DHC-4 Caribou has a long history of operational activity from Amberley and part of the fleet was based there until two years ago.
Australia received a total of 29 DeHavilland Canada Caribou between 1964 and 1971.
The light tactical transport aircraft were well known for their ability to operate from short and unprepared airstrips.
In recent years, the ageing Caribou became increasingly costly to operate, a major problem being that the Twin Wasp radial engines were no longer in production, although ADM understands that CASA stockpiled a few, perhaps for private aircraft restorers.
And because it was the only aircraft in the ADF inventory to use AVGAS, this led to logistical difficulties.
According to Air Power Australia, in late 2000, several Australian companies and an American company, Pen Turbo Aviation, proposed to Defence a private financed initiative for re-engining the Caribou, on similar lines to a study completed by DeHavilland Canada during the 1980s.
Pen Turbo had a prototype flying with the R-2000 Twin Wasp radials replaced by Pratt and Whitney Canada PT6A-67T turboprop engines conveying a general improvement in hot and high performance.
At the normal all-up weight of 12.9 tonnes and with STOL capabilities maintained, the DHC-4T prototype had demonstrated a 15 per cent increase in maximum payload, substantial improvement in payload/range figures and a small increase in cruising speed.
The proposal was for austere refurbishment with two re-engined aircraft on lease for training while ADF Caribou were sequentially modified for $US3-4 million each, but it seemed that the Air Force did not intend to pursue re-engining.
Other Caribou have been provided to the Australian War Memorial and to the RAAF Museum at Point Cook, Victoria.
Shown below is the Pen Turbo prototype.
