NOVA | D-Day’s Sunken Secrets
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Watch Wednesday, May 28, 2014 at 9pm on WMHT TV.

On June 6, 1944, the Allies launched the D-Day invasion against the heavily defended Normandy beaches to liberate Europe from the Nazis. In less than 24 hours, more than 5,000 ships—the largest armada in history—crossed the English Channel, along with thousands of tanks and landing craft and 200,000 men. Throughout the operation, hundreds of ships sank while running the gauntlet of mines and bunkers, creating one of the world’s largest underwater archaeological sites. Now, 70 years later, NOVA has exclusive access to a unique international collaboration between military historians, archaeologists, and specialist divers as they carry out the most extensive survey ever done of the seabed bordering the legendary Normandy beachheads. The teams use submersibles, underwater robots and the latest 3D mapping tools to discover, identify and plot the relics on the sea floor.

D-DAY’S SUNKEN SECRETS chronicles the ambitious 6-week expedition led by Sylvain Pascaud, Director of Operations, to explore the famous landing beaches of Normandy, a vast sanctuary that holds sunken ships, tanks, planes and explosive mines. The remarkable expedition was made possible through a unique international collaboration between NOVA and various organizations in Great Britain, Canada, and France.

The major undersea project reveals how the Allied Forces’ intricate planning and advanced technology were vital in assuring the success of the most ambitious and risky military operation ever launched.  The expedition focuses their three-dimensional scanning sonar on the disintegrating wrecks and relics of World War II in the hopes of uncovering the untold story of this submerged battlefield. The team also utilizes divers and robotic rovers to get closer views of the myriad of objects below. NOVA interviews several military historians—including Adrian Lewis, Professor of History at Kansas University and a former Army Ranger who taught cadets at West Point—to answer some important questions about the military operation and strategy:  Where did the landing ship actually end up?  Do the location of the ships reveal a pattern—or a flaw in the planning?  And why are so many Sherman tanks located off only one of the landing beaches?

In addition to finding wrecks that reveal battlefield secrets, the expedition brings to life the personal histories of aging WWII War heroes.  Small submarines take several intrepid D-Day veterans back in time 70 years—in some cases to the very ships that had been sunk by the Germans. Among them is Bill Allen, a Tennessee Navy medic veteran, 19 years old at the time, who was one of only 28 survivors of the Landing Ship Tank (LST) 523, which was hit by a German mine and sank off the Normandy coast.  NOVA’s cameras are there to film as Allen bravely climbs into one of the expedition’s three-man mini submarines to explore the wrecks in hope of finding his old ship. 

Much of the hardware deployed in D-Day was part of a huge effort in both Germany and among the Allies to develop the weapons, the airplanes, the landing crafts, and all kinds of innovations that could turn the tide of the war.  Each invention had the promise of tipping the balance towards victory. A beach assault would require engineering wholly new ways to land an invading army, and the necessary gear and supplies that the operation entailed. 

D-DAY’S SUNKEN SECRETS explores how some of the innovations deployed in the invasion led to the Allied Forces’ successful campaign:

  • Floating Sherman Tanks: One of most extraordinary ideas was to make the 30-ton Sherman tank, needed in the first wave to take out Nazi gun emplacements, float. Nicholas Straussler, a Hungarian-born engineer living in England, designed an inflatable skirt that came up on the sides of the tank and turned the vehicle into a rather poorly designed, but adequately floating boat.
  • Man-Made Mulberry Harbors: A wildly ambitious idea developed by the British to build a harbor at the beaches of Normandy where there was no major existing harbor to unload the supplies needed for battle. Mulberry Harbors were designed, tested, and constructed in Britain, customized to the specific hydrographical and topographical conditions—including Normandy’s epic tides—and then transported across the English Channel and re-erected in just a few days.  
  • Hobart’s Funnies: A series of unique and peculiar inventions were developed to overcome the beach obstacles that the Germans had constructed. These included flail tanks, bangalores, and other minesweeping devices used to clear paths through the beach mines, fill in trenches and build bridges.
  • Waco Gliders: Fabric and wood gliders were created to land small units of soldiers behind enemy lines prior to D-day. These stealth gliders were designed to fall apart so they could land in small fields and secure key sites in advance of the Normandy invasion.
  • Meteorology:The elected day to launch the entire operation also came down to two critical elements:  the tides in the English Channel and the weather. Various charts, maps, and timetables went into selecting the exact time and place of the landings. Teams of scientists studied how the tides affected the depth of the water at the beaches—crucial data for determining the lowest tides of the year and how close the landing ships could pull up to the beaches—allowing for most of the German beach obstacles and mines to be exposed, and for there to be sufficient time to unload enough men and machinery to overcome the German threat.  Inclement weather in the English Channel also ultimately delayed the operation a day and allowed the Allied to travel towards Normandy undetected.

Few battles of the war were more strategically important than the D-Day Invasion at Normandy. In D-DAY’S SUNKEN SECRETS, NOVA shows that it was a combination of extraordinary operational planning along with significant scientific innovations that ultimately led the Allies to prevail. The complexity that went into the design, engineering, and implementation of the entire D-Day operation can be appreciated by the fact that 70 years after the invasion, we are still in awe of what was accomplished.