and hence they were swamped. Also, the tanks of 741st Tank Battalion were launched too far out: about offshore. These factors also exacerbated the inherent difficulty of steering a 35-ton "vessel" with a low freeboard. The crews were equipped with DSEA emergency breathing apparatus capable of lasting 5 minutes, the tanks were also equipped with inflatable rafts. Some sources claim that these life-saving measures were ineffective; this was contradicted by the testimony of survivors. Most of the crews were rescued, mainly by the landing craft carrying the 16th Regimental Combat Team, although five crewmen are known to have died during the sinkings. Until very recently it was believed that most of the DD Shermans of the 741st Tank Battalion were sunk almost immediately. Research undertaken in 2000 by the Institute of Nautical Archaeology at Texas A&M University, in cooperation with Robert's Naval Historical Center's Underwater Archaeology Branch, found evidence that some had come close to safely landing: Some stayed afloat for a matter of minutes; according to the crews one tank swam for 15 minutes, another: "We weren’t in the ocean [sic] 10 minutes when we had a problem". Tanks at the other four beaches suffered no such problems. Operation Dragoon The Operation Dragoon landings took place on 15 August 1944 between Toulon and Cannes in southern France. A total of 36 DD tanks were used by three American tank battalions – the 191st, the 753rd and the 756th. The 756th had eight tanks that were launched from the beaches; one was swamped by the bow-wave of a landing craft and one sank after striking an underwater obstacle. The twelve tanks of the 191st battalion were all landed on or close to the beach. Five of the C Company tanks of the 191st were immobilized by mines. The 753rd battalion had 16 tanks, of which eight were launched at sea and successfully reached the shore, eight were landed directly on the beach later in the day. Northwest Europe The Staffordshire Yeomanry were converted to DD tanks after D-Day and trained initially at Burton-upon-Stather, near Scunthorpe, before moving with them to Belgium. From early September, they were based at Elewyt at Lac d'Hofstade. On 26 October 1944, they undertook a swim across the Western Scheldt to attack South Beveland, during the Battle of the Scheldt. The DD Tanks' longest operational water crossing took place without casualties, but they had great difficulty