On June 6, 1944, along fifty miles of coastline, thousands of warships and landing craft crowded a gloomy dawn horizon for the greatest invasion in military history. Nearly seven thousand vessels, including over four thousand landing craft, ferried more than one hundred and fifty thousand Allied troops across the English Channel toward five landing zones.
American flags with forty-eight stars fluttered across the massive flotilla, rising above the sea like a bed of nails. Kite balloons floated hundreds of feet above the armada, poised to shield the infantry from strafing Luftwaffe gunners. Engines groaned, winches spun, chains clattered, and troops clambered down wet ladders and webbed nets into the beaching transports. Combat engineers carrying blasting caps and explosives dived into the frigid waves to destroy obstacles like defensive cables and underwater mines.
Massive LSTs—tank-landing ships with giant bow doors that could open at sea—carried in their steel bellies hundreds of peculiar boats with wheels. Designed by one of Van Bush’s protégés at the Office of Scientific Research and Development, the engineer Palmer Putnam, the odd steel chariots backed off the LST ramps into the drink. They puttered strangely low in the water. The Army called them DUKWs, a tortured acronym indicating that the vehicles were amphibious and equipped with all-wheel drive and dual rear axles. GIs called them “duck” boats.
Allied ships carried medicine, first-aid kits, and hundreds of pints of blood. Medics carried a blood substitute called serum albumin, a mixture of globular proteins derived from whole blood that helped prevent shock and death in cases of massive blood loss. The lifesaving substitute was developed by doctors working for Bush and OSRD’s Committee on Medical Research.
Thanks to Bush’s recruits, medical officers also brought penicillin as an all-purpose antibiotic. Two billion pills of a new strain of penicillin were available that day, a striking feat considering that when work began in 1941, there wasn’t enough penicillin in the United States to treat a single person. A team headed by OSRD’s Robert Coghill had cultivated the antibiotic and increased its yield by one hundred times. The medicine was brewed inside huge vats of a liquid byproduct of corn.
D-Day troops carried secret “beach barrage rockets.” They were intended to strike Nazi positions on the coast during the vital period after Allied air support operations were over, but before mortars and field artillery could make it ashore. With a range of eleven hundred yards, the rockets produced virtually no recoil and used lightweight launchers. Self-described “rocketboatmen” waited patiently in landing craft to fire the missiles, devised by OSRD’s Section L, to soften the shoreline.
Troop carriers, landing craft, cruisers, and battleships carried hundreds of radar jammers and electronic countermeasure devices. The gadgets broadcast clogging, confusing beams toward any German radar installations that might still be working. To install the devices, countermeasure specialists culled from Bush’s scientists had canvassed British ports from Exeter, in southern England, all the way to Scapa Flow, north of mainland Scotland. Many of the jammers now among the Normandy fleet had been devised by OSRD recruits.
These scientists were a linchpin of the larger scheme to keep the Nazis ignorant of exactly where and when the invasion would arrive. Troop movements had been faked by large tent cities in open English fields, where no one lived, where dirt roads leading into the woods ended nowhere, and where stoves were kept smoking for Luftwaffe reconnaissance photographers. Car headlights were rigged to look like airplane blinders and driven up and down fake runways at night. Inflatable rubber tanks, trucks, and antiaircraft guns were ballooned to replace the real deal, while “fleets” of fake wood-and-canvas ships floated on old oil drums.
Allied airplanes hauled hundreds of dummy parachutists—three-foot-tall burlap soldiers complete with miniature boots and helmets. Floating in the distance, they were easily mistaken for soldiers. Real paratroopers were guided by British electronic-targeting gadgets. American bombers executed raids on Nazi sites along the Normandy coast using a ground-scanning radar devised, with British help, by OSRD scientists at the Massachusetts Institute of Technology.
Outside of the Normandy landing zones, Allied aircraft carried “Window”—bundles of the same metallic strips dropped in the air by the British before the Peenemünde raid. To Nazi radar, they looked like flocks of bombers. Below the fluttering strips, decoy vessels tugged blimps with special radar reflectors that made them read like imposing warships. A phantom fleet complete with air cover approached the French coast in the Pas-de-Calais region, northeast of Paris, filling German radar screens and confusing the Luftwaffe dispatched to meet it. Thanks to “the most sophisticated faking in the history of man,” as one historian put it, a “ghostly procession of nonexistent battleships, cruisers, destroyers, transports, landing craft, and air squadrons swam into the Germans’ ken.”
The Normandy invasion was not opposed by sea or by air.
Off Utah Beach, as Allied planes saturated the coastline with bombs, the rocket boats neared the shore ahead of the first wave. “Boat, machine guns, rockets, and six man crew, everything was expandable as hell,” a soldier recalled. One unit was closer to the beach “than the hitter is to the left field screen at Fenway Park” when it let loose its barrage of missiles against Nazi machine-gun and mortar emplacements.
Gunfire pinged the armored hulls.
The troop transports made land, and the hinged steel ramps slammed into the waves and wet sand as the soldiers rushed from the waterway. The guns and shells on the beach were so loud GIs could not hear themselves talk.
Behind them, Landing Control Craft, or LCCs, carried special navigation equipment invented by Bush’s scientists. They chaperoned amphibious tanks from four thousand yards offshore to four hundred. As the violent struggle began, the LCCs assembled, led, and dispatched wave after assault wave from the transport area.
A medical boat sank, spilling packets of blood plasma. The bobbing soldiers made it ashore, stuffed their pockets with the substitute serum albumin, and administered the lifesavers to bleeding GIs until they could be evacuated. Medics applied tourniquets and dressed wounds that would be treated with penicillin.
Out of the sea on Utah and Omaha Beaches, the First, Fifth, and Sixth Engineer Special Brigades piloted hordes of duck boats through underwater passageways still bristling with piercing beams and deadly mines. They risked drowning from punctured hulls, overloaded cargo, bent propellers, and busted rudders. Receiving gunfire, the peculiar ships that reached the beaches rose majestically from the brine to reveal craft far taller than their seaborne profiles suggested. In place of propellers, six wheels gripped the sand and strained to ferry high-priority engineering equipment, artillery, and ammunition onto shore.
Duck boats would carry 40 percent of all supplies up the beaches. The stunning figure contradicted the Nazi skeptics who’d claimed the Allies would not be able to amass enough equipment to muster a fighting force that could challenge them.
The day after the invasion began, D+1, Allied ships carried additional curious contraptions to France. Temporary harbors, one in the British landing zone and another in the Americans’ off Omaha Beach, sprang up. Composed of piers attached to metal pylons on the sea floor, they could rise and fall with the help of hydraulic jacks. Steel pontoons, floating roadways, connected the piers to shore while breakwaters beyond them, guarding against waves in a great arc, were formed by deliberately sinking old ships and linking together huge watertight chambers.
To protect the harbors, British trawlers carried troops from the American Chemical Warfare Service along with their M1 mechanical smoke generators. M1s weighed three thousand pounds when empty and fifty-four hundred when filled with fog oil, fuel oil, and water. While the Battle of Normandy erupted, the generators belched white plumes, shrouding the artificial harbors to protect them from attack. The chemical formula was the brainchild of OSRD’s David Langmuir.
Allied hulls also ferried Section T fuses designed for Army 90 mm guns. The smart weapons crossed the English Channel in crates of ten, or with single fuses in hermetically sealed metal containers, each with a key and a tear strip for opening, like a tin of sardines. Twelve such containers were packed with a special wrench in padded cardboard cartons enclosed in a steel box. They were headed for gun positions on the beaches to help guard the makeshift harbors.
Transports carried key personnel like Captain Bert Mitchell, who had worked on Section T’s fuse at National Carbon. Mitchell trained the antiaircraft battery commanders on the ins and outs of the new gadget in a hayloft of a French barn.
Only senior officers were provided details of the weapon, which the Army called “Pozit.” They were told that the device sensed enemy aircraft “electromagnetically” and exploded within sixty feet of a plane. They were warned that the Nazis must not get their hands on it, and that if capture was imminent, the fuses must be destroyed—an incendiary explosive would do it. Enlisted men were taught to remove the plug and gasket from the shells and screw in the fuses like light bulbs.
As the Allies pushed deeper into France, American antiaircraft gunners waited for the Luftwaffe to bomb the harbors. Yet the fuses were not needed.
The Germans had bigger problems. And bigger plans.
Within days, an airplane carried two of Bush’s scientists to France. One was Guy Stever, a twenty-seven-year-old radar expert (and later chief science adviser to Presidents Nixon and Ford). The second was Bob Robertson, a forty-one-year-old mathematician and physicist from Princeton and an essential OSRD liaison.
On the morning of June 6, minutes after the invasion of Normandy had begun, Stever and Robertson met with R. V. Jones. Their mission, joint with the British, was to follow in behind the troops as the Allies made headway into France, and to gather intelligence about Hitler’s military science.
The V-1 ski sites were a key target of interest.
The pair landed in a C-47 on a small dirt runway above Omaha Beach. The Nazis were still shelling the French town of Carentan when they drove through it, up the Cotentin Peninsula, toward the port of Cherbourg. Stever saw the wreckage of the gliders that had tried to land on D-Day and crashed into trees, walls, and hillsides. The men camped with an engineering unit in a field surrounded by winding country lanes, woodland, pastures, small trees, and high hedges.
They slept in pup tents to the cracks and whistles of shells passing overhead: German rounds from the southwest; American shells retaliating from the northeast. The Norman hedges seemed to offer an illusion of security, as if their tents were merely seats in a cosmic theater, and the countryside were a vast planetarium, and they were really invulnerable to the shells flying under the stars.