07/03/2013: After visiting the memorials in St. Naizare, the families of the B-17 crew visited one of the targets of the raid 70 years ago — the Nazi U-boat base.
The base is a heavy reinforced facility with anti-aircraft protection. Obviously, this was a high value target but also one very difficult to strike.
The base is 300 meters long, 130 meters wide and 18 meters high, amounting to a 39,000 m² surface on the ground, and a volume of concrete of 480,000 m³. The roof is 8 meters deep, featuring four layers: the first one is a 3.5 meter sheet of reinforced concrete; the second is a 35 cm granite and concrete layers; the third is a 1.7 meter deep layer of reinforced concrete, and the fourth, is a “Fangrost” layer of steel beams, 1.40 meters deep. The roof is dotted with anti-aircraft weaponry, machine guns and mortars.
The base offers 14 submarine pens. Pens 1 through 8 are dry docks, 92 meters long and 11 meters wide; pens 9 through 14 are simple docks, 62 meters long and 17 meters wide, each holding two submarines.
Between pens 5 and 6, and 12 and 13, are two areas giving access to the upper levels of the base.
The base was equipped with 62 workshops, 97 magazines, 150 offices, 92 dormitories for submarine crews, 20 pumps, 4 kitchens, 2 bakeries, two electrical plants, one restaurant and a hospital.
For a good look at life at a French U-boat base, the following book provides significant unvarnished details:
Steel Boat Iron Hearts: The Wartime Saga of Hans Goebeler and U-505
We have several pictures of our visit, including marks left behind by members of the U-boat crews. Credit Photos: Second Line of Defense
Credit Photos: Pierre-Anne and Robbin Laird, Second Line of Defense:2013