Encyclopedia Astronautica
Martlet



martfam2.jpg
Martlet Family
In 1962-1967 Canada's Gerard Bull led development of the Martlet system for gun-launched access to space. The program was cancelled before the objective of gun launch to orbit was attained.

Even after the rocket established its primacy as a method of accessing space, Gerald Bull of the Canadian Armament and Research Development Establishment began a life-long struggle to use guns for cheap access to space.

In the 1950's Bull pioneered the use of gun-fired models as an economical approach to study supersonic aerodynamics. The model was fitted with a wooden shell, or sabot, that matched the diameter of the gun barrel. After leaving the barrel the sabot would fall away and the model would continue, with high-speed cameras recording its behaviour in flight.

By 1961 Bull had expanded his concept and obtained a $10 million joint contract from the US and Canadian Defence Departments for a High Altitude Research Program (HARP). This was to prove the feasibility of using large guns for launch of scientific and military payloads on sub-orbital and orbital trajectories.

For long range shots a range was established at Barbados, where the payloads could be sent eastward over the Atlantic. A surplus 125 tonne US Navy 16 inch gun was used as the launcher. The standard 20 m barrel was extended to 36 m, and converted to a smooth-bore. In 1962 - 1967 Bull launched over 200 atmospheric probes to altitudes of up to 180 km.

By this time relations between Canada and the United States were strained because of the Viet Nam war. Canada terminated the project.

More... - Chronology...


Associated Launch Vehicles
  • Martlet Canadian gun-launched orbital launch vehicle. In 1962-1967 Canada's Gerard Bull led development of the Martlet system for gun-launched access to space. The program was cancelled before the objective of gun launch to orbit was attained. More...
  • Martlet 2 Canadian sounding rocket. The Martlet 2 series were the primary 16" gun-launched sub-orbital flight vehicles used during the High Altitude Research Program (HARP). Martlet 2's were used to conduct extensive research at altitudes of up to 180 km with some 200 flights being conducted between 1963 and 1967. The very low cost per flight, about $3,000, made it ideal for a wide variety of applications.. Typical mission payloads included chemical ejection to produce an observable atmospheric trail and assorted sensors with multi-channel telemetry. More...
  • Martlet 1 Canadian sounding rocket. The Martlet One Flight Vehicle was designed in mid-1962 as a first generation test vehicle for the HARP project. The primary role of the Martlet One was to test the fundamental technologies that were to be used in the Martlet Two vehicle. These included the internal ballistics of the 16" L45 smooth-bored gun system, the pusher plate/ laminated plywood sabot system and the ability to receive radio telemetry from a gun launched vehicle in flight. More...
  • Martlet 3 Canadian sounding rocket. Single stage, gun-launched vehicle. More...
  • Martlet 3B Canadian sounding rocket. Once the fundamental design flaws of the Martlet 3A vehicle were identified the system was redesigned and a new vehicle, the Martlet 3B, was created.

    The Martlet 3B vehicle was similar in design to the 3A vehicle but sported several design changes intended to improve the system performance. The first major change was to replace the aluminium airframe with a alloy steel airframe in the hopes the stronger material would lead to higher mass fractions. Other improvements included the use of a larger diameter rocket motor (increasing the outer diameter to 8 inches / 20 cm) and the use of six fixed fins instead of the 3A's four fins. More...

  • Martlet 3A Canadian sounding rocket. The Martlet 3A was the first serious attempt to produce a sub-calibre, gun-launched, rocket-assisted, vehicle for the 16 inch gun system. The basic design criteria for the Martlet 3A was to gun launch a vehicle containing a rocket motor that could provide a velocity boost equal to or greater then the initial gun-launch velocity.

    The theoretical performance of the Martlet 3A was for an 18 kg payload to be carried to an altitude of some 500 km at gun-launch accelerations of 12-14,000 g's and gun launch velocities in the range of 2100 m/sec (similar to the Martlet 2 series maximum launch parameters). More...

  • Martlet 4 Canadian gun-launched orbital launch vehicle. The Martlet 4 was ultimate goal of the HARP program - a gun-launched orbital launch vehicle. Two versions were considered: a preliminary version with two solid propellant upper stages, and a later model with two liquid propellant upper stages. Payload of the liquid propellant version would have reached 90 kg. The initial version was in an advanced stage of suborbital flight test when the HARP program was cancelled in 1967. More...
  • GLO-1B Canadian gun-launched orbital launch vehicle. When compared to the early Martlet 4 designs the GLO-1B was a considerably more sophisticated vehicle with many of the shortcomings of it's predecessor having been addressed. Not long after the original HARP project ended the major assets of the project were acquired by the projects management, Dr. Gerald Bull in particular. The HARP Program became the Space Research Corporation (SRC) with the intention of resurrecting the HARP orbital program. Over the years a much improved and considerably more sophisticated Martlet 4 was developed and given the name of GLO-1B. More...
  • Martlet 2G-1 Canadian gun-launched orbital launch vehicle. The Martlet 2G-1 was the absolute minimum gun-launched satellite vehicle. Conceived when the HARP project was under threat, it was a seven-inch diameter, two-stage solid propellnat vehicle that would be sabot-launched from the HARP 16 inch gun. Its total payload in orbit would have been just two kilogrammes - ideal for today's planned nano-satellites. Unfortunately even this minimum orbital launch vehicle could not be demonstrated before the program was shut down. More...
  • Martlet 2G Canadian sounding rocket. This derivative of the Martlet 2 gun-fired suborbital space probe achieved a higher scientific payload through use of a lighter sabot. 12 were flown before the program was ended. More...
  • Martlet 3D Canadian sounding rocket. The Martlet 3D concept was intended to serve as a sub-orbital vehicle capable of lifting heavy payloads to satellite altitudes. The Martlet 3D was simply the first stage of the Martlet 4 vehicle ( Martlet 4A) with the two upper stages and the satellite payload being replaced with a single large payload. More...
  • Martlet 3E Canadian sounding rocket. The Martlet 3E vehicle was designed to take advantage of the portability of the HARP 7 inch guns. Unlike the big fixed 16 inch guns the 7 inch HARP guns, were portable and could be relocated to conduct launches from a wide variety of sites. It was soon determined that a gun-launched rocket vehicle for the 7 inch gun would have a similar performance to the Martlet 2 glide probe launched from the fixed 16 inch guns. Launch costs would also be about the same. More...

Associated Launch Sites
  • Barbados Sounding rocket launch site located on island in the Caribbean. It was also from here that Gerard Bull tested his Martlet series of gun-launched sounding rockets. Known to have been used for 40 launches from 1963 to 1968, reaching up to 150 kilometers altitude. More...
  • Yuma Sounding rocket launch location known to have been used for 16 launches in 1966, reaching up to 180 kilometers altitude. More...

Martlet Chronology


1962 June - . LV Family: Martlet. Launch Vehicle: Martlet 1.
  • Martlet One Flight Vehicle designed - . Nation: Canada. Summary: This was the first generation test vehicle for the HARP project..

1963 - . LV Family: Martlet. Launch Vehicle: Martlet 1.
  • The Martlet One Flight Vehicle was designed in mid-1962 as a first generation test vehicle for the HARP project. The primary role of the Martlet One was to test the fundamental technologies that were - . Nation: Canada. The main body of the vehicle was intended contain coloured chemicals for release during flight to produce a visible trail. This was to allow the wind and atmospheric conditions to be observed along the flight path. (primarily wind shear at altitudes near apogee). Ground observers were to determine the effect of high altitude winds on the chemical trail. The nose was designed to hold a small one watt radio telemetry transmitter and other electronic instruments.

    Only four Martlet Ones were manufactured. Two were flown during the initial test series and the remaining two were retired. The first Martlet One was launched on January 21, 1963. It was launched at an elevation of 80 degrees and flew for 145 seconds. During its flight it rose to an altitude of 26 km and landed 11 km down range. The second Martlet One was launched on February 1, 1963 and flew for 146 seconds. It rose to an altitude of 27 km and landed about 11 km down range. These two flights were sufficient to prove the launch concept. The initial test series also included several wooden test slugs.

    The Martlet 1 series was retired in favour of the much improved Martlet 2 family of vehicles. Also, the cost of installation of the gun and the ground support infrastructure left precious little funds for an extensive initial test series.

    MARTLET ONE SPECIFICATIONS

    • Mass: 205 kg (450 lb.)

    • Body Diameter: 0.168 m (6.6 inches)

    • Length: 1.78 m (70 inches)

    • Sabot: Metallic pusher plate with four laminated plywood centring petals; outside diameter of sabot 0.417 m (16.4')

    • Gun Launcher: 16.4 inch L45 smooth-bored gun. This was a standard 16 inch battleship gun which had the rifling bored out. Propellant load 330 kg cordite.

    by Richard K Graf


1963 - . Launch Site: Barbados. Launch Complex: Barbados HARP. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Test mission - . Nation: Canada. Agency: HARP. Apogee: 80 km (49 mi).

1963 January 21 - . LV Family: Martlet. Launch Vehicle: Martlet 1.
  • Martlet 1 Shot 1 - . Nation: Canada. Agency: HARP. Apogee: 26 km (16 mi). Summary: The gun-launched rocket was shot at an elevation of 80 degrees and flew for 145 seconds. During its flight it rose to an altitude of 26 km and landed 11 km down range..

1963 February 1 - . LV Family: Martlet. Launch Vehicle: Martlet 1.
  • Martlet 1 Shot 2 - . Nation: Canada. Agency: HARP. Apogee: 27 km (16 mi). Summary: The second Martlet One flew for 146 seconds. It rose to an altitude of 27 km and landed about 11 km down range. These two flights were sufficient to prove the launch concept. The initial test series also included several wooden test slugs..

1963 June 18 - . Launch Site: Barbados. Launch Complex: Barbados HARP. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Test mission - . Nation: Canada. Agency: HARP. Apogee: 92 km (57 mi).

1963 September 5 - . Launch Site: Barbados. Launch Complex: Barbados HARP. LV Family: Martlet. Launch Vehicle: Martlet 3.
  • Test mission - . Nation: Canada. Agency: HARP. Apogee: 100 km (60 mi). The Martlet 3A gun-launched rocket program began in the spring of 1963 with test flights beginning in September. Early Martlet 3A test flights were less then successful. At launch loads of 5000-6000 gs the rocket motor fuel grain would fail.The Martlet 3A set a world record as the largest rocket launched from a gun.

1964 January 1 - . Launch Site: Barbados. Launch Complex: Barbados HARP. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Test mission - . Nation: Canada. Agency: HARP. Apogee: 80 km (49 mi).

1964 June - . LV Family: Martlet. Launch Vehicle: Martlet 3B.
  • Martlet 3B final test flight - . Nation: Canada. Summary: The last test flights of the Martlet 3B were performed in mid-1964 after which no further work was performed by HARP on sub-calibre gun-launched rocket vehicles..

1965 March - . LV Family: Martlet. Launch Vehicle: Martlet 4.
  • Martlet 4 orbital gun-launched rocket design. - . Nation: Canada. It was not until 1964, when agreements between the Canadian and the US governments permitted stable funding over the following three years, that HARP was able to seriously consider an orbital program. The Martlet 4 program began in the spring of 1965 with extensive parametric studies which showed that meaningful payloads could be launched into low Earth orbit from the 16 inch L86 HARP gun on the Barbados flight range using a full bore, 3 stage rocket vehicle.

1965 June 3 - . 20:54 GMT - . Launch Site: Barbados. Launch Complex: Barbados HARP. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Ionosphere mission - . Nation: Canada. Agency: HARP. Apogee: 105 km (65 mi).

1965 June 5 - . 20:20 GMT - . Launch Site: Barbados. Launch Complex: Barbados HARP. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Ionosphere mission - . Nation: Canada. Agency: HARP. Apogee: 120 km (70 mi).

1965 June 5 - . 22:43 GMT - . Launch Site: Barbados. Launch Complex: Barbados HARP. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Ionosphere mission - . Nation: Canada. Agency: HARP. Apogee: 117 km (72 mi).

1965 July 1 - . Launch Site: Barbados. Launch Complex: Barbados HARP. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Ionosphere mission - . Nation: Canada. Agency: HARP. Apogee: 150 km (90 mi).

1965 September 20 - . 23:30 GMT - . Launch Site: Barbados. Launch Complex: Barbados HARP. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Aeronomy mission - . Nation: Canada. Agency: HARP. Apogee: 80 km (49 mi).

1965 September 21 - . 00:52 GMT - . Launch Site: Barbados. Launch Complex: Barbados HARP. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Aeronomy mission - . Nation: Canada. Agency: HARP. Apogee: 80 km (49 mi).

1965 September 21 - . 04:24 GMT - . Launch Site: Barbados. Launch Complex: Barbados HARP. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Aeronomy mission - . Nation: Canada. Agency: HARP. Apogee: 80 km (49 mi).

1965 September 21 - . 07:35 GMT - . Launch Site: Barbados. Launch Complex: Barbados HARP. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Aeronomy mission - . Nation: Canada. Agency: HARP. Apogee: 80 km (49 mi).

1965 September 21 - . 09:00 GMT - . Launch Site: Barbados. Launch Complex: Barbados HARP. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Aeronomy mission - . Nation: Canada. Agency: HARP. Apogee: 80 km (49 mi).

1965 September 22 - . 23:24 GMT - . Launch Site: Barbados. Launch Complex: Barbados HARP. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Aeronomy mission - . Nation: Canada. Agency: HARP. Apogee: 80 km (49 mi).

1965 September 23 - . 05:50 GMT - . Launch Site: Barbados. Launch Complex: Barbados HARP. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Aeronomy mission - . Nation: Canada. Agency: HARP. Apogee: 80 km (49 mi).

1965 September 23 - . 07:15 GMT - . Launch Site: Barbados. Launch Complex: Barbados HARP. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Aeronomy mission - . Nation: Canada. Agency: HARP. Apogee: 80 km (49 mi).

1965 September 23 - . 08:07 GMT - . Launch Site: Barbados. Launch Complex: Barbados HARP. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Aeronomy mission - . Nation: Canada. Agency: HARP. Apogee: 80 km (49 mi).

1965 September 23 - . 09:05 GMT - . Launch Site: Barbados. Launch Complex: Barbados HARP. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Aeronomy mission - . Nation: Canada. Agency: HARP. Apogee: 80 km (49 mi).

1966 September - . LV Family: Martlet. Launch Vehicle: Martlet 4.
  • Martlet 4A orbital gun-launched rocket tests. - . Nation: Canada. Development trials for the Martlet 4A began in the fall of 1966 with tests proceeding into early 1967. The majority of the early work was conducted on the Highwater, Quebec test range where the structural integrity of the Martlet 4A motor during gun-launching was proven. Prior to the abrupt end of the HARP project in July 1967, soft recovery trials and flight testing had been planned for the winter of 1967/1968. At nearly one ton the Martlet 4A holds the worlds record for being the largest rocket motor ever fired from a gun.

1966 November 17 - . 01:41 GMT - . Launch Site: Yuma. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Y-10 Meteorites mission - . Nation: USA. Agency: USA. Apogee: 112 km (69 mi).

1966 November 17 - . 02:41 GMT - . Launch Site: Yuma. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Y-11 Meteorites mission - . Nation: USA. Agency: USA. Apogee: 119 km (73 mi).

1966 November 17 - . 05:32 GMT - . Launch Site: Yuma. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Y-12 Meteorites mission - . Nation: USA. Agency: USA. Apogee: 112 km (69 mi).

1966 November 17 - . 07:16 GMT - . Launch Site: Yuma. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Y-13 Meteorites mission - . Nation: USA. Agency: USA. Apogee: 120 km (70 mi).

1966 November 18 - . Launch Site: Yuma. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Test mission - . Nation: USA. Agency: USA. Apogee: 180 km (110 mi). A Martlet 2C launched from the 16 inch L86 gun established the world altitude record for a sub-orbital gun-launched projectile. A Martlet 2C was fired to an altitude of 180 km with a flight time of over 400 seconds. Launched from Yuma Proving Ground, Arizona - Latitude: 32.87 N, Longitude:114.32 W.

1966 November 19 - . 01:18 GMT - . Launch Site: Yuma. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Y-14 Meteorites mission - . Nation: USA. Agency: USA. Apogee: 120 km (70 mi).

1966 November 19 - . 02:12 GMT - . Launch Site: Yuma. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Y-15 Meteorites mission - . Nation: USA. Agency: USA. Apogee: 127 km (78 mi).

1966 November 19 - . 04:49 GMT - . Launch Site: Yuma. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Y-16 Meteorites mission - . Nation: USA. Agency: USA. Apogee: 139 km (86 mi).

1966 November 19 - . 06:43 GMT - . Launch Site: Yuma. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Y-17 Meteorites mission - . Nation: USA. Agency: USA. Apogee: 138 km (85 mi).

1966 November 19 - . 08:01 GMT - . Launch Site: Yuma. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Y-18 Meteorites mission - . Nation: USA. Agency: USA. Apogee: 144 km (89 mi).

1966 November 19 - . 09:35 GMT - . Launch Site: Yuma. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Y-19 Meteorites mission - . Nation: USA. Agency: USA. Apogee: 120 km (70 mi).

1966 November 19 - . 11:52 GMT - . Launch Site: Yuma. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Y-20 Meteorites mission - . Nation: USA. Agency: USA. Apogee: 167 km (103 mi).

1966 November 20 - . 02:45 GMT - . Launch Site: Yuma. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Y-21 Meteorites mission - . Nation: USA. Agency: USA. Apogee: 142 km (88 mi).

1966 November 20 - . 04:21 GMT - . Launch Site: Yuma. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Y-22 Meteorites mission - . Nation: USA. Agency: USA. Apogee: 111 km (68 mi).

1966 November 20 - . 05:37 GMT - . Launch Site: Yuma. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Y-23 Meteorites mission - . Nation: USA. Agency: USA. Apogee: 111 km (68 mi).

1966 November 20 - . 06:59 GMT - . Launch Site: Yuma. LV Family: Martlet. Launch Vehicle: Martlet 2.
  • Y-24 Meteorites mission - . Nation: USA. Agency: USA. Apogee: 147 km (91 mi).

1967 June 30 - . LV Family: Martlet. Launch Vehicle: Martlet.
  • HARP project closed down - . Nation: Canada. The cancellation came only a few months before an orbital 2G-1 could be flown. Martlet 2's were used to conduct extensive research at altitudes of up to 180 km with some 200 flights being conducted between 1963 and 1967. The very low cost per flight, about $3,000, made it ideal for a wide variety of applications.. Typical mission payloads included chemical ejection to produce an observable atmospheric trail and assorted sensors with multi-channel telemetry.

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