Source : royal naval library : http://www.royalnavalmuseum.org/info_sh ... bakkuk.htm
The Habbakuk Project
HABBAKUK: GEOFFREY PYKE'S ICEBERG AIRCRAFT CARRIER
In 1942, the Allied forces were losing a considerable amount of merchant shipping in the Atlantic Ocean, due to German submarine forces and the lack of adequate air cover in the mid-Atlantic. The range of operating aircraft was not sufficient to cover this area and aircraft carriers were in short supply to allow for shorter range flying. Plans for an Allied invasion of Europe were also underway and it was felt that large floating platforms were needed to assist the assault forces. The Second World War was also a time when many scientists were encouraged to develop weapon technology and other military equipment to assist the war effort. Many projects that were developed were successful, such as the bouncing bomb by Barnes Wallis, midget submarines, mulberry harbours and the Pipe Line Under The Ocean (PLUTO) project. Others were not so successful and some were even incredible.
Lord Louis Mountbatten was Chief of Combined Operations and part of the work of this department was to develop technology and equipment for offensive operations. He encouraged scientists to produce their ideas, however fantastical they might seem. Many ideas did not get past the drawing stage, but others were taken up and experimented with before being abandoned. One such idea was that of an iceberg aircraft carrier, and this project was enthusiastically endorsed by both Mountbatten and Churchill.
Habbakuk was the idea of a scientist called Geoffrey Pyke. His idea was that because ice was unsinkable, the berg ships would be insulated and impervious to bomb and torpedo attacks. They would be easy to repair as water only had to be poured into holes and frozen, thus making the ship whole. The ships would be cheap to make so that a vast number could be made. The ships could be up to 4000 feet long, 600 feet wide and 130 feet in depth. They could be used to carry aircraft to protect shipping in the mid-Atlantic, since the aircraft would be able to operate at shorter ranges and could be used for an invasion force base. He christened the idea (misspelling the name in the process) after the words from Habakkuk, the Old Testament prophet: “Behold ye among the heathen, and regard and wonder marvellously: for I will work a work in your days, which ye will not believe, though it be told to you.” Hab. 1:5
The idea was taken up by Mountbatten and in December 1942, Churchill was convinced that the idea was worth pursuing. One problem had to be overcome. Ice split too easily and Pyke suggested the addition of some kind of building material could solve the problem. In 1943, two American scientists made a compound out of paper pulp and sea water which was almost as strong as concrete. This substance was named “Pykecrete”, after Pyke. Plans were drawn up for a vessel with the dimensions of 2000 feet long with a displacement of 1,800,000 dead weight tons. For the best possible results, the ship would need to be built in Canada or Russia, where the ship could be naturally frozen. The budget for continuing with the experimental ship was limited to £5000.
In the summer, a model was built on Patricia Lake, Jasper in Canada. It became essential that the Americans were brought into the project as they would be needed to supply large quantities of steel for the vessel. Costs were already spiralling due to technical and supply problems. Mountbatten took a block of Pykecrete to Quebec to demonstrate the idea to the Americans. He intended to show them the strength of Pykecrete as opposed to ice. He fired a revolver into a block of ice which, predictably, shattered. He then fired into a block of Pykecrete. The bullet did not penetrate the block, rather it ricocheted off the ice, and unfortunately struck the American Chief of Naval Operations in the process, but without injury.
The Americans were not convinced about the project. They felt that due to technical problems, the ice ships would not be ready until 1945, and by this time, the conventional carrier fleet would be large enough to make the need for ice aircraft carriers obsolete. Churchill also gave up on the project when he realised that the carriers would cost over £6m.
The model in Patricia Lake was “scuttled” in 1943 by removing all the machinery that had been used and leaving it to sink in place. In the 1970’s remains of the model were found and studied and in 1989, a plaque to commemorate the unusual ship was placed on the lake’s shore.
© Royal Naval Museum Library, 2001
The information contained on this information sheet is correct as far as we are able to ascertain from our sources. It is not intended to be an exhaustive or complete history of the subject. Please contact the library for a bibliography of further reading materials, if available.
http://laplumeetlerouleau.over-blog.com ... 15372.html
En 1941, l’aviation alliée reçoit des missions qui excèdent parfois le rayon d’action des avions, notamment lorsqu’il s’agit d’escorter les convois de navires dans l’Atlantique pour les protéger des attaques des sous-marins allemands. Aucun porte-avion par ailleurs, ne peut à l’époque transporter des bombardiers lourds.
Il est donc envisagé de construire en plein océan des îles artificielles pour procéder notamment au bombardement du Japon. Un seul problème : l’approvisionnement en acier dont les quantités nécessaires seraient alors considérables.
Alors Pyke a une idée complètement farfelue : pourquoi ne pas utiliser de la glace en guise de porte-avions ? Churchill est enthousiaste. On envisage d’aller découper des morceaux de banquise dans l’Atlantique nord et de les tracter en mer.
Problème : la glace fond (eh oui !). Pyke embauche alors une équipe de biochimistes spécialistes des plastiques pour travailler sur le durcissement rapide de la glace : c’est le « projet Habbakuk ». Ces hommes, dont certains sont des autrichiens qui ont fui le nazisme, mettent au point un procédé performant : en ajoutant 4 % de pulpe de bois à un volume d’eau, on obtient une glace ultra-résistante. Les torpilles s’y enfoncent sans la faire éclater, on peut la travailler comme du bois et la couler comme de l’acier ! On appelle cette matière (consécration !) la « pykrete ».
Pour en prouver la solidité, on invite Lord Mountbatten et on tire au pistolet sur le bloc de glace. Si l’initiative manque de tourner au drame (la balle ricoche sur la glace et passe de peu à côté de l’anglais !), elle montre en revanche que des résultats concrets voient le jour.
Pour limiter la fonte (car la glace fond, on se le rappelle, c’est incontournable), on envisage d’isoler la coque et de la réfrigérer en la maintenant à moins 15 degrés.
Et c’est parti. Des ingénieurs se mettent à dresser les plans d’un mirobolant navire porte-avions de glace jaugeant 2 millions de tonneaux (26 fois le Queen Elisabeth !), nanti d’une piste pour bombardiers lourds de 700 mètres de long et 70 mètres de large, résistant aux torpilles et doté de 26 moteurs développant 33 000 chevaux. Une oeuvre titanesque, entièrement en glace !
Le délire ne s’arrête pas là. On envisage de lui faire transporter des citernes permettant de projeter sur les ports ennemis de l’eau qui se transformerait immédiatement en glace, gelant les défenses et immobilisant les soldats pendant que débarqueraient des commandos alliés.
En août 1943, une conférence sur le projet Habbakuk réunit alors Lord Mountbatten, Roosevelt et Churchill qui, impressionnés, donnent leur accord pour construire dès l’hiver 1943 à Terre-neuve une immense usine de réfrigération d’où sortirait le premier prototype.
Mais durant l’été, Mountbatten est muté en Asie. Les américains se rendent alors compte (il est temps !) de l’absurdité du projet...
