Canadair DC-4M North Star

Canadair North Star

North Star
BOAC DC-4M-4 Argonaut G-ALHS "Astra" at London Airport (Heathrow) in September 1954
Role Passenger and cargo transport
Manufacturer Canadair
First flight 15 July 1946
Introduced 1946
Retired 1960s (RCAF), 1975 (last civil operator)
Primary users Trans-Canada Air Lines
Royal Canadian Air Force
Canadian Pacific Air Lines
Produced 1946 - 1950
Number built 71
Developed from Douglas DC-4

The Canadair North Star was a 1940s Canadian development of the Douglas C-54 / DC-4 aircraft. Instead of radial piston engines found on the Douglas design, Canadair employed Rolls-Royce Merlin engines in order to achieve a 35 mph faster cruising speed. The prototype flew on 15 July 1946 and the type was selected by various airlines as well as by the RCAF. It provided reliable, if noisy, service throughout the 1950s and into the 1960s. Some examples continued to fly into the 1980s as converted cargo aircraft.

Design and development

Canadair Aircraft Ltd. took over the Canadian Vickers Ltd. operations on 11 November 1944. Besides the existing Consolidated PBY Canso flying patrol boats in production, a development contract to produce a new variant of the Douglas DC-4 transport, was still in effect. The new Canadair DC-4M powered by Rolls-Royce Merlin engines emerged in 1946 as the "North Star." More than just an engine swap, the North Star had the Douglas DC-6 nose, landing gear and fuselage shortened by 80 in (2 metres), DC-4 empennage, rear fuselage, flaps and wing tips, C-54 middle fuselage sections, wing centre and outer wing panel, cabin pressurisation, a standardized cockpit layout and a different electrical system.

Canadair built 71 examples under the designations: North Star, DC-4M, C-4 and C-5. With the exception of the single C-5 (which had the Pratt & Whitney R-2800 engines, as fitted to the Douglas DC-6), these variants were all powered by Rolls-Royce Merlin engines and 51 of the production examples were pressurized.

Operational history

Trans-Canada Air Lines (TCA), the Royal Canadian Air Force (RCAF), Canadian Pacific Airlines (CPA) and British Overseas Airways Corporation (BOAC) were the principal operators of the "North Star", with the CPA examples known as the "Canadair Four" and BOAC examples known as the "Argonaut".

RCAF service

The RCAF North Stars were unpressurized and were used on a wide variety of general transport duties. Like other North Stars, they were also unfortunately notorious for the high level of interior cabin noise caused by the Merlin engines (since the Merlin engine is supercharged using a two-stage geared engine-driven supercharger, its exhaust is not run through a turbocharger, and thus exits the exhaust manifold in high-pressure bursts).

The sole C-5 variant was consequently powered by Pratt & Whitney R-2800 Double Wasp engines (that were considerably quieter). The only C-5 was delivered to the RCAF in 1950, entering service with No. 412 Transport Squadron in Uplands, Ottawa. In RCAF service, the C-5 was specially outfitted for the transportation of VIP passengers. It was then used to transport the Canadian Prime Minister, the Queen, and numerous other dignitaries on various high profile missions. It served faithfully for 17 years, later becoming a crew trainer before being retired and sold in the United States.

North Stars were also employed by 412 Squadron from Ottawa on various VIP transport duties and, overall, the aircraft provided valuable and reliable long range transport services for the RCAF. From 1950 to 1952, during the Korean War, RCAF North Star aircraft were employed ferrying supplies to Korea across the Pacific Ocean. They flew 599 round trips over the Pacific and delivered seven million pounds of cargo and 13,000 personnel on return trips. They flew 1.9 million miles without a fatal crash and outhauled the USAF C-54 on the Korean run. After 1967, the remaining North Stars were assigned to No. 426 Transport Squadron initially deployed to Dorval, Quebec and then to Trenton, Ontario. Gradually, their service life diminished in the 1970s and most were declared surplus.

TCA and BOAC operations

In commercial operations, the North Star had a relatively lengthy career as a passenger airliner. TCA received their fleet of 20 DC-4M-2 North Stars during 1947 and 1948 and operated them on routes within Canada, to the USA and from Canada to Europe until 1961. In an attempt to deal with constant complaints about noise, T.C.A. engineers developed a special cross-over exhaust that was only a partially successful in reducing noise levels.

BOAC ordered 22 DC-4M-4 aircraft and named them as their "Argonaut class", each aircraft having a classical name prefixed with "A". The Argonauts were delivered between March and November 1949; they flew to South America, Africa and the Far East from London Airport (later Heathrow) until 1960.

Later service

After service with TCA and BOAC, the surplused North Stars and Argonauts had long careers with secondary operators like British Midland, Overseas Aviation and other charter companies. Cargo conversions of available airframes also lengthened the service life of Argonauts and North Stars.CF-UXA,ex-RCAF 17510 was the last DC-4M in airline service, carrying out its final flight 19 June 1975 at Miami, Florida. Despite the onset of jet airliners in the 1950s, the rugged Canadair North Star found a niche in both military and civil use.



Civil operators


Military operators


Accidents and incidents

Surviving North Stars

A small number of surviving airframes are still in existence including an RCAF C-54GM example (17515 ) which is currently undergoing restoration at the Canada Aviation Museum, Ottawa, Ontario.

Specifications (DC-4-M2 North Star)

General characteristics


See also

Related development

Related lists


  • Eastwood, Tony and John Roach. Piston Engine Airliner Production List. West Drayton, UK: Aviation Hobby Shop, 1991. ISBN 0-907178-37-5.
  • Milberry, Larry. The Canadair North Star. Toronto: CANAV Books, 1982. ISBN 0-07-549965-7.
  • Pickler, Ron and Larry Milberry. Canadair: The First 50 Years. Toronto: CANAV Books, 1995. ISBN 0-921022-07-7.

External links

Retrieved from : http://en.wikipedia.org/wiki/Canadair_North_Star