Loki (rocket)

A Loki-Dart (foreground) on display at the White Sands Missile Range rocket garden

Loki, officially designated 76mm HEAA Rocket T220, was an American unguided anti-aircraft rocket based on the German Taifun. Like the Taifun, Loki never saw service in its original role, but later found widespread use as a sounding rocket. It was so successful in this role that several advanced versions were developed on the basic Loki layout, including the final Super Loki.

Development

As part of their anti-aircraft development program of 1942, the Luftwaffe began developing a number of guided missile projects. However, there was concern that these would not develop in time to be useful in the 1943/44 time frame. To fill the gap, Klaus Scheufelen suggested building a simple unguided rocket that would be fired en-masse directly up into the bomber streams. The result was the Taifun.

Taifun was powered by a hypergolic mixture pressure-fed into the combustion chamber. The pressure was provided by small cordite charges that were fired into the fuel tanks, in the process bursting a pair of thin diaphragms to allow the fuel and oxidizer to flow into the combustion chamber. The Germans were never able to get the engine to work reliably, and the rocket was never deployed operationally.

The US Army had initially studied the Taifun in 1946, and the German engineers now working for the Army were convinced the concept deserved more development.[1] When similar concerns about the development time of their own guided missile projects were raised, the Taifun was reconsidered and a development program started at Bendix in 1948. One major change was to replace the warhead area with a dart-like version, which was separated from the main rocket body at engine burnout to continue on without the drag of the airframe and thereby reach higher altitudes.

Like the Germans before them, Bendix had significant problems with the engine, and eventually decided to develop a solid-fuel engine based on a new elastomeric fuel from the Jet Propulsion Laboratory (JPL), starting in March 1951. The first flight of a solid-fuel Loki occurred on 22 June 1951.[2] The new engine was successful, and the liquid engine was abandoned in February 1952.

An initial meeting on Jun 25 1954 at the Redstone Arsenal of Dr. Wernher von Braun, Frederick C. Durant III, Alexander Satin, David Young, Dr. Fred L. Whipple, Dr. S. Fred Singer, and Commander George W. Hoover resulted in an agreement that a Redstone rocket with a Loki cluster as the second stage could launch a satellite into a 200-mile orbit without major new developments.[3]

JPL eventually fired 3,544 Lokis at White Sands during the testing program. These tests demonstrated that the launch of one rocket would affect the flight path of the ones behind it, making the dispersion too large to be a useful weapon.[4] Although this problem was studied in depth, it appeared there was no obvious solution. The Army eventually gave up on Loki in September 1955, in favour of the Nike-Ajax missile, which had recently reached operational status, and the MIM-23 Hawk which was expected to be available shortly.[5]

Loki specifications

  • payload: 3.2 kg (dart)
  • dimensions:
    booster: 2.63 m long × 76 mm diameter
    dart: 1.02 m long × 35 mm diameter
  • weight:
    booster: 13 kg
    dart: 3.2 kg
  • maximum height: 55 km
  • maximum speed 6,275 km/h
Other Languages
Deutsch: Loki Dart
español: Loki (cohete)
português: Loki (foguete)