Canadair CL-44 / CC-106 Yukon
The RCAF was looking for replacements for it's C-54GM North Star to provide personnel and logistics support for Canadian Forces in Europe. Canadair had already acquired a licence for the Bristol Britannia and announced in January 1957 plans for a fleet of long range transports based on the Britannia. Canadair received a contract for 8 aircraft, later increased to 12, designated CL-44-6 and CC-106 by the RCAF.The design used the modified Argus wings and controls. The fuselage was almost identical to the Britannia 300 with two cargo doors on the left-hand side. The cabin was pressurised to maintain a cabin altitude of 2.400m at 9.000m (30,000 ft). The Yukon could accommodate 134 passengers and a crew of nine and in the casualty evacuation role it could take 80 patients and a crew of 11. The RCAF had specified the CL-44 to be equipped with Bristol Orion engines but when the British Ministry of Supply dropped the Bristol Orion, the RCAF decided to use the Rolls Royce Tyne 11.
The roll out of the Yukon was a disaster all over. When the prototype was supposed to be pushed out of the hangar the tail was too high. The first plane took off 15 November 1959. During test flights all kind of problems where encountered from complete electrical failure to engines shaking loose and almost falling off. Rolls Royce had problems delivering engines resulting in "Yukon gliders" being parked outside Canadair as late as 1961.
Once in Service the Yukon proved very well and on December 1961 a Yukon set a world record for its class when it flew 10.860 Km (6.750mi) from Tokyo to Trenton, Ontario, in 17 hours three minutes at an average speed of 640 Km/h (400 mph). Later a Yukon even set a new record staying airborne for 23 hours and 51 minutes. These records stayed untouched until broken by the new 747SP in 1975. Eleven Yukons flew for 437 Transport Squadron. Two flew as VIP transports for 412 Squadron.
The RCAF needed an aircraft, which could operate as an in-flight refuelling tanker, and there was a chronic shortage of spares as the CL-44 had never gone into large-scale production. Consequently spare parts tended to be in short supply and relatively expensive. All Yukons were sold to South American and African operators since it could not be registered in Northern America or Europe since the Britannia windshields did not meet new security standards. The Yukons retired in March 1971 and were replaced by Boeing 707.
At a similar time as the Yukon contract came in Canadair announced its intentions to re-enter the civilian market with a slightly modified Yukon. The plane generated little interest with the passenger airlines, but cargo airlines found the cost projections made by Canadair compared with the high operating cost of Super constellations and DC-6B interesting.
The Flying Tiger Line and Seaboard World Airlines pushed Canadair to develop a system to load and unload the 29.5 tons of cargo in 45 minutes enabling turn-around in less then 60 minutes. This became the "Swingtail". After the initial eight Yukons, Canadair built the first civilian CL-44 with a swingtail, designated CL-44D4. The APU that the Yukon carried in the nose was removed to increase payload and Canadair built the plane without a launch customer. This Aircraft, serial #9, used as a demonstrator for many years, was built in 1960 but not sold to Loftleidir until 1965.
While the prototype was being built a problem arose as the FAA refused to certify the Britannia type windshields for its vision standards. The Convair CV880/990 windshields were compatible enough to be adopted into the flight deck structure. A requirement was set for structural fatigue testing. The CL-44 had to simulate 80,000 flight hours in a watertank to be certified for 40,000 hours.
The Flying Tiger Line ordered 12 aircraft and Seaboard World Airlines ordered 7 aircraft. Pakistan ordered five aircraft, but the Canadian government refused to issue an export permit for Pakistan for fear of offending India. Saudi Arabia withdrew their two aircraft after the Pakistan cancallation. Japan Cargo Airlines ordered three Aircraft but cancelled after Japan airlines opposed the purchase. BOAC appeared to be a certain client until their management changed and stopped the discussion. (BOAC Cargo later leased a D4 from Seaboard while waiting for their new Boeing 707).In 1960 the USAF Military Air Transport Service (MATS) was thinking of buying up to 232 D4’s. The United States wanted Canada to bolster its northern fighter defences and proposed a deal whereby the Canadian would buy 100 F-101 Voodoo fighters plus a possible participation in the maintenance of the Pinetree early warning radar line. The quantity of D4’s had dwindled to 37 when Ontario conservatives objected on the grounds that it would be politically unacceptable to award a major aircraft contract to Quebec after having cancelled the Ontario-built Avro Arrow. MATS quickly changed their minds and bought Boeing C-135.Canadair built a Total of 39 CL-44 aircraft. 12 CC-106 Yukon and 27 CL-44D4. Seaboard World Airlines bought seven aircraft and The Flying Tiger Line bought twelve. Later Slick Airways ordered four more. This left Canadair with the unsold prototype and three CL-44D4s already finished but not sold. Canadair knew that the Icelandic low fare carrier Loftleidir was searching for alternatives to replace their ageing fleet of DC6B. Loftleidir bought those with the condition that they would all be stretched to accommodate more passengers. An engineering office in the United States on behalf of Loftleidir carried out a study to stretch the CL-44. Canadair carried out the work and the first stretched D4 flew on November 8, 1965. Loftleidir had already taken the other three D4s into service but returned them one after another in order to be converted.
Another D4 was converted by Jack Conroy Aviation of California into a CL-44-0 "Guppy". This aircraft had its upper fuselage removed and replaced by an enlarged section, which raised the cabin height by 1.5m.The forty-four proved to be a nightmare for mechanics. But it was an extremely profitable aircraft to run. At the time the fuel burn of a CL-44 was half compared to a Boeing 707.
After 40 years, out of the 39 built, 17 either crashed or were destroyed in operation. 19 aircraft have been cut up.
No CL-44 has been preserved.