TCS Daily

The Amazing PLUTO

By Sallie Baliunas - September 14, 2004 12:00 AM

The initial press of Allied troops and equipment onto Normandy's beaches starting on D-Day, June 6, 1944, had to be supplemented with soldiers and supplies until Fortress Europe was liberated, nearly a year later.

The U.S. Army had estimated it would need to wrest ashore16 million tons of equipment and material into an initially occupied Europe. Besides food, medicine and ammunition, the Army planned to use fleets of motorized equipment -- 137,000 jeeps, trucks and half-tracks, more than 4,200 tanks and tracked vehicles, 12,000 aircraft and 3,500 large artillery pieces. So much mechanized equipment would require plentiful, steady supplies of fuel.

Hence, reopening the ports of Cherbourg and Le Havre were high priority objectives, but they also were expected to be centers of Nazi sabotage, while supply ships would make attractive targets for the Luftwaffe.

The Allied Forces' need for so much equipment and fuel arose in part from its stepped up modernization and mechanization efforts, which were vital in defeating German forces.

One symbol of the slower modernization of the German forces was carried by its infantry troops. It came in the form of the weapon that had been standard issue since 1898, the Mauser Gewehr 98 rifle.

Although extremely reliable, the Mauser rifle could only be fed one of its five, strip-loaded rounds with a clumsy, single-bolt action hand feeding after each firing. In contrast, the U.S. Army and Marines by 1942 had left their single-bolt action Springfields and advanced to the semi-automatic M1 Garand, which after firing a 0.30-caliber round automatically loaded its next from its box of eight. The improved swiftness in chambering its next round meant the Garand could fire more quickly than the Mauser. In Gen. George S. Patton, Jr.'s retrospective opinion, the M1 was "the finest battlefield implement ever devised."

The German Army's relatively low level of mechanization also meant moving most of its soldiers on foot, with soldiers and horses hauling much equipment in carts. Petroleum was mainly reserved for the Panzer and motorized infantry, plus ships and aircraft.

The anticipated Allied fuel demands were recognized early by Allied command as a critical tactical supply problem, even in the pre-invasion planning that had begun in September 1941.

Adm. Lord Louis Mountbatten, Chief of Combined Operations, pushed for fuel supplied from England to France by way of an imaginary and seemingly fantastic pipeline running under the Channel. By August 1944 audacious British engineering talent had begun to deliver fuel through the highly secret Pipe Line Under The Ocean, or PLUTO project. PLUTO became the main fuel supply route for the winter and spring Allied campaigns of 1944 and 1945.

PLUTO began to materialize in 1942 when Mr. A.C. Hartley, chief engineer for the Anglo-Iranian Oil Co., envisioned a hollowed-out telegraph cable of the type manufactured by Siemans Brothers and Co. of London laid by submarines. Since the pipeline could not be assembled on the Channel floor, it would have to be assembled ashore from pieces to its full length, and rolled out by drum traveling across the sea surface. The pipe needed to be flexible and lightweight enough to be quickly deployed from surface ships, so that meant a small diameter pipe. Yet it needed to be strong enough to withstand the high pressure at the sea floor, and be sturdy enough to resist leaking. It was easy to say, but was it possible to do?

The answer from engineers was a resounding "Yes!" with two designs ultimately succeeding. The first, the Hais (Hartley-Anglo-American-Siemens) consisted of a three-inch diameter lead pipe wrapped with insulation and steel wire for strength, enveloped in a coating of yarn and tar. The second design, based on the experience of the oil field engineers B.J. Ellis and H.A. Hammick, was a flexible three-inch diameter steel pipe, designated the Hamel (Hammick-Ellis).

Many skilled technical specialists made PLUTO work, including chief chemist of Shell Petroleum Co. of London, John Augustus Oriel, nearly blind as a result of a gas attack during World War I, and Samuel Hunter Gordon, head of the AI Welders in the Highlands.

When finished, the first Hais pipe was wrapped around a giant spool-shaped "conun" drum that became the HMS Conundrum, towed by the freighter HMS Holdfast and unreeled the first of four lines from the Isle of Wight 70 miles southwest across the Channel to Cherbourg. As the Allies advanced eastward, 17 lines (6 Hamel and 11 Hais types) were installed across the 30 miles from Dungeness to Ambleteuse near Boulogne; by then other pipe-laying ships were operational, including HMS Latimer, Sandycroft and Algerian.

The pipeline system began well inland in England and coastal pumping stations were disguised as modest houses or shops, with one an ice cream parlor, to camouflage them from the Luftwaffe. In the spring of 1945, PLUTO consisted of over 500 miles of pipe delivering over 1 million gallons of fuel per day. By VE Day PLUTO had delivered over 172 million gallons of Allied oil to Europe.

Gen. Dwight D. Eisenhower, Supreme Allied Commander, recognized the enormous challenge accomplished when he wrote that PLUTO was "second in daring only to the artificial harbours project." Engineers had solved a nearly impossible problem of reliably delivering most of the fuel needed for the last step in liberating Europe, with simple faith in hard work and inventiveness.

Good reading

Normandy, by William M. Hammond, U.S. Army Center of Military History, available online at

PLUTO - Pipe Line Under the Ocean, by Adrian Searle, published by Shanklin Chine, Isle of Wight, 2004, 126 pages.

Operation Pluto at


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