Yes, that is correct!

The battle sled, invented by Brig. Gen. John W. O'Daniel (Truscott's successor as commander of the 3d Division), was half a torpedo shell, just large enough to hold one soldier lying down. Six were hooked together and attached to each side of a tank and the twelve sleds were pulled forward in the paths made by the tank's tracks, enabling an infantry squad to accompany a tank without being exposed to small arms fire and antipersonnel mines. After O'Daniel sent Ordnance a sketch of what he wanted, Colonel Jaynes and his staff developed a model with runners, to prevent heat from friction, and made the sleds in an atmosphere of the greatest secrecy in a field near the Capua shops. They set up a production line, using 80 welding sets in stalls under a big circus tent, and with the expert supervision of Sergeant Sellfors as chief welder, Fifth Army and PBS mechanics working in 8- hour shifts manufactured 360 sleds between 29 April and 14 May.


All the sleds were used in the breakout at Anzio. The worst impediments were ditches and mines that immobilized the tanks. In one regiment a platoon of tanks and four sets of sleds failed to get into action because of rough ground and the loss of several tanks from mines; in another, the results were negligible because the terrain was unsuitable; in a third unit, the towed infantry, supported by the tanks, took a strongly fortified house. Infantrymen were not enthusiastic about the sleds because they felt like "dead ducks" lying so close behind the tanks. General O'Daniel felt that the combat test was not conclusive, and that these special devices should be employed against organized positions when terrain and antitank defenses permitted. Half the sleds were salvaged from the battlefield and used in the invasion of southern France.

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Best Regards,
JW