Blasts and Boosts

How the Norseman Almost Became a Jet!

Most aviation enthusiasts recognize the ear-shattering takeoff roar of fully loaded Noorduyn Norseman bushplanes. Hot glassy lakes or sub-zero deep snow, one float out of the water or none, it seems to make little difference. "Canada's Own," as a Noorduyn factory rep once called it, stands out as an airplane requiring a long takeoff run. A takeoff run that most bush pilots learned to live with.
Since the fabric-covered Norseman made its first appearance in 1935, however, pilots, mechanics, and non-flyers have come up with many suggestions to help the pug-nosed freighter struggle over the shorelines. One of the most peculiar came from a southern Ontario politician who brought up the question of using solid fuel rocket boosters. The Aerojet Engineering Company of Pasadena, California, claimed that a JATO or Jet Assisted Take Off bottle could slam a Norseman into the air in 20 seconds or 500 feet.

Click on the images for a larger view.Norseman Floatplane

George Ponsford, chief of the Ontario government's Provincial Air Service or OPS thought the idea might have merit. Always cautious before spending taxpayer money, he sent memorandums to several of his experienced bush pilots with a request for takeoff statistics. During the 1940's the famous OPAS "Yellow Birds" operated eleven Norsemans to haul conservation officers, fire fighters, surveyors, and treaty parties throughout the northern reaches of the province.
"What I am trying to determine is whether or not, in the opinion of those who fly the Norseman an ATO (Auxiliary Takeoff Unit) would be, if any, particular advantage, " he said.
Reports quickly came back to OPAS head quarters in Sault Ste. Marie. Pilot Winston Buckworth said a Norseman CF-OBE at a 7,540 pound (imperial) gross weight with 15 degree of flap averaged 34 seconds to lift off on a half-mile run. Ponsford estimated that 15 seconds after attaining the on-the-step or planing position would be the moment to fire the rockets. Aerojet indicated that from that point, its JATO bottles provided eleven seconds of blast and boost.
Aerojet vice-president Dan A. Kimball offered to send an engineer from California to winter-locked Canada to push the project. Not easily swayed, Ponsford discreetly queried manufacturer Robert B.C. Noorduyn in Montreal. Noorduyn, however, was not impressed, especially since each JATO unit weighed at least 430 pounds.
"The Norseman is about the most unsuitable airplane anyone would think of as an external structure would have to be built on to it to take the tremendous thrust of the jets, "he said." The only way I can think of would be to build it on the float undercarriage struts and the great drag of such a structure would be carried around throughout the ensuing flight, cutting down the speed and climb."
The project went no further than Ponsford's desk after a survey pointed out that solid fuel propellants were restricted to military purposes and in short supply. No one mentioned that highly flammable wood, fabric, and dope made up much of the Norseman airframe. A slight swing of the rocket's flame path would have rendered the venerable freighter into a tangled mass looking more like a barbecued muskrat than the classic airplane it truly was. Not a word appeared anywhere about the effects of JATO blasts on Indian settlements from Attawapiskat to Pauingaussi.
The concept of boosters did not fade quietly. In 1946, California researchers attached six rockets to the wings of a tiny, two seat Ercoupe. The pilot, a brave one, ignited a blend of perchlorate, asphalt, and special oils with an instrument panel switch. In a blinding flash of light and dense smoke, he launched himself in only 300 feet and 7.5 seconds instead of the Ercoupe's usual 581 feet and 13.1 seconds.
"Should there be a separation between the fuel and the walls of the combustion chamber, then the flame could penetrate and set off the whole charge in an explosion," wryly remarked an unimpressed Canadian Aviation writer.

Noorduyn Norseman
Noorduyn Norseman, first Canadian airplane designed with flaps, was entirely covered in fabric and treated with weatherproof dope. Several later models were metallized but the pug-nosed freighter would have been a poor candidate for JATO bottles.

Canada's first successful civil JATO demonstration took place on June 11, 1947 when a metal-bellied Fairchild Husky F-11 took 12 seconds to thunder into the sky over Cartierville, Quebec. Surprisingly, pilots D.D. Murphy and A.M. McKenzie reported only " ...a very slight sensation of acceleration." The tail had not been raised until Husky CF-SAQ reached 25 miles per hour.
In 1960, Bristol Aero Industries of Winnipeg entered the picture after convincing themselves that customers would clamour for JATO on everything from single engine sport airplanes to heavy transports. They produced drawings for a belly installation on a Cessna 180 but never sold one. The company also built a mock-up to fit a de-Havilland Beaver. Bulky and costly, it never went beyond a trial installation and civil use of firecracker-powered airplanes never took off in Canada.

Note from  Just for the record the JATO units on the Ercoupe did not use the asphalt perchlorate propellants mentioned. That propellant was used in the production units that were 200, 500, and 1000 lb thrust. That propellant never exhibited any tendency to de-bond from the walls as described. The units on the Ercoupe were NEVER used on any aircraft by Aerojet again; that was the only instance.

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Editor John S Goulet


Last modified on April 28, 2007.
Virtual Horizons, 1996.