MANUFACTURER(S): State Arsenals - UK
OPERATORS: Canada; United Kingdom
Detailing the development and operational history of the Projector, Rocket 3-inch, No 8 Mk 1 (Land Mattress) Towed Multiple Rocket Projector.
Entry last updated on 5/2/2017.
Authored by Staff Writer. Content ©www.MilitaryFactory.com.
Compared to the Germans and the Soviets, the British (along with the Americans) were late in developing useful portable rocket projectors as additional artillery support systems. Such weapons proved their value along the East Front where they were used with extreme lethality to soften concentrations of enemy forces at range. While largely inaccurate per individual rocket fired, a collection of rockets landed in an area offered excellent saturation and offered the secondary benefit of being psychologically detrimental to enemy forces finding themselves on the receiving end of such instruments. The British eventually introduced their famous "Land Mattress" rocket projector during the latter half of 1944. Its long form name was "Projector, Rocket 3-inch, No. 8 Mk 1".
The Land Mattress was named as such due to it following the naval-based version which was known as the "Sea Mattress". The land-based version incorporated either sixteen or thirty launch tubes arranged neatly within block shape. The block then sat atop a mounting device as part of a two-wheeled carriage. The carriage utilized two rubber-tired road wheels for travel with a folding tow arm at the front. This allowed the Land Mattress unit to be transported behind a mover vehicle to wherever it was needed.
Its rocket payload revolved around the RP-3 ("Rocket Projectile 3-inch") rocket, an air-to-surface High-Explosive (HE) rocket already in use with British warplanes and known by its 60lb warhead as the "60lb". Each rocket held a diameter of 76.2mm and mounted a 5" TNT/TN/RDX-filled naval shell as its warhead. Propulsion came from a solid fuel rocket with cordite as its propellant. Muzzle velocity of each exiting rocket was rated at 1,160 feet per second, the entire salvo able to be launched in around seven seconds. The unit held a maximum engagement range of 7,900 yards which provided plenty of "reach".
Land Mattress weapons were tested under combat action during mid-1944 and saw service through to the end of the war in 1945 and for a time thereafter until retired from formal service. It was operated by both British and Canadian forces.