On an English Beach · September 7, 1943

On this date in 1943, on a popular beach near a sea­side vil­lage in South­western Eng­land, the Brit­ish mili­tary not so secretly tested a giant rocket-pro­pelled, explo­sive-laden con­trap­tion called the Pan­jan­drum, known also as The Great Pan­jan­drum. The highly experi­mental vehicle con­sisted of a pair of 10‑ft‑high steel tread wooden wheels mounted on an axle. Its purpose was to breach Adolf Hitler’s Atlan­tic Wall defenses in North­ern France, thereby per­mitting an amphib­i­ous landing force to suc­cess­fully stake out a beach­head during Opera­tion Over­lord, the battle to liber­ate Europe from the scourge of the Third Reich. To that end each vehicle was designed to carry a 2,200‑lb pack­age of explo­sives in the wheel’s hub. The vehicle would storm across the invasion beaches, deto­nate on hard im­pact against con­crete or wooden beach defenses, and blast a tank-sized breach in such a wall.

In August 1943 con­struc­tion of a proto­type began in East London. Within a month the proto­type was ready for testing in a beach setting. On the day of the test, the 18‑roc­ket vehicle cata­pulted out of the landing craft used as a launch pad and trundled a short way up the sandy ter­rain, chased by a dog no less, before a num­ber of the rockets on the right wheel failed and the weapon careered off course. Several more trials were con­ducted as late as January 1944, during which the vehicle, aug­mented by more rockets, a set of steering cables, and in one test a third wheel, some­times fell dan­ger­ously on its side, cor­dite rockets exploding or breaking off and flying in all directions, terrifying the VIP spectators.

The Pan­jan­drum never made it up the beach or, fortu­nately, into battle. Other, equally experi­mental wea­pons managed to pass mus­ter and enter the Allied armed ser­vices, including two anti­sub­marine mor­tars, the Hedge­hog and the Squid. Squid salvos proved so effec­tive in crushing the hulls of enemy sub­marines that the wea­pon system was still in use by Royal Navy as late as April 1977.

Wartime Research: Some Experimental Weapons Passed Muster and Entered Service, Some Didn’t

Experimental weapons: Great Panjandrum 1Experimental weapons: Great Panjandrum 2

Left: The British Admiralty’s Depart­ment of Miscel­laneous Wea­pons Develop­ment (DMWD) was respon­sible for a num­ber of devices of varying practi­cality and suc­cess. Their out­put en­com­passed both resounding suc­cesses and sub­limely comi­cal fail­ures. Among the latter was the Great Pan­jan­drum rocket-propelled beach defense demolition weapon shown here.

Right: The Great Panjandrum, or simply Pan­jan­drum, revolved using pro­pul­sion from rockets arranged around its cir­cum­ference. Sadly, tests in the months before the inva­sion revealed the wea­pon was too un­stable, repeatedly careering off course as its rockets mis­fired and it hit bumps and small craters in the beach at its North Devon testing ground.

Experimental weapons: Hedgehog anti-submarine mortarExperimental weapons: Squid anti-submarine mortar

Left: The Department of Miscellaneous Weapons Devel­op­ment also devel­oped suc­cess­ful and impor­tant wea­pons. The Hedge­hog anti­sub­marine wea­pon was a ship-mounted 24‑barreled mor­tar. It was deployed on convoy-escort war­ships such as destroyers to supple­ment the depth charge. The wea­pon fired a num­ber of small spigot mortar bombs from spiked fittings up to 280 yards from the ship. The 30- to 35‑lb bombs exploded on con­tact rather than using a time or depth fuse as depth charges did. They achieved a higher kill rate against submarines than conventional depth charges did.

Right: Another DMWD success story was the Squid anti­sub­marine mor­tar. It replaced the Hedge­hog. The Squid con­sisted of a three-bar­reled mor­tar that launched depth charges up to 275 yards ahead of the ship. Carrying a 207‑lb charge, the wea­pon was auto­ma­tically fired in a tri­an­gular pat­tern from the sonar range recorder at the pro­per moment. The Squid’s first suc­cess­ful use was on July 31, 1944, when a Brit­ish frigate sank U‑333 in the North Atlan­tic, followed on August 6, 1944, with killing U‑736 in the Bay of Bis­cay west of Saint-Nazaire, France. The Squid system, nine times more effec­tive than con­ven­tional depth charges, was credited with sinking 17 German submarines in 50 attacks.

Mulberry Harbor, Omaha Beach, June 1944Destroyed Mulberry Harbor, Omaha Beach, late June 1944

Left: Mulberry “A” pontoon cause­way with supply truck. The DMWD played an instru­mental role in devel­oping parts of the two arti­ficial Mul­berry har­bors used in the D‑Day landings. By June 9, 1944, just 3 days after D‑Day, Mul­berry “A” and “B” har­bors were con­structed at Omaha and Gold beaches, the Amer­ican and British invasion beaches, respectively.

Right: Wrecked Mulberry “A” pon­toon cause­way, the result of a huge three‑day gale on June 19–22, 1944. The gale, the worst in 40 years, de­stroyed the Mul­berry har­bor at Omaha Beach before the whole of the break­water had been laid, leaving only the Brit­ish har­bor at Gold Beach still intact. Mul­berry “B” came to be known as Port Win­ston, named after Brit­ish Prime Minis­ter Win­ston Chur­chill. Port Win­ston saw heavy use for 8 months—despite being designed to last only 3 months. In the 10 months after D‑Day, it was used to land 4 mil­lion tons of sup­plies (its ini­tial rai­son d’être), over 2.5 mil­lion men, and 500,000 vehi­cles, pro­viding much-needed rein­force­ments in France. The cap­tured Bel­gian port of Antwerp eliminated the need to maintain Port Winston.

Experimental British Weapons of World War II