Tail Support Stanchion dampens aircraft movement during ground operations. Models 705C and 745B are for use on the Boeing 747 Freighter and Combi during cargo operations to dampen aircraft movement caused by changes in center of gravity and weight. Nose door sill movement is reduced 50-80%. Model 705C is designed for Fixed location operations while the 745B is a Flyaway unit for ULD air transport on a 125 in. x 88 in. pallet. Model 705C & 745B are ??Unipod?? type units with a tripod support structure. The stanchions are rated at 15 tons and may be pre-loaded with the integral hand pump to any load up to 25,000 pounds. The stanchion load ram is then a solid column at loads up to 25,000 pounds. When the load exceeds the limit, a pressure relief valve opens to a gradual retracting of the load ram. The ram will return to a solid column when the load reduces to approx. 22,500 pounds. This hydraulic dampening effect occurs slowly to restrain aircraft vertical movement. As aircraft center of gravity shifts forward, or weight decreases, the stanchion ram extends with the aircraft until a compressive load is reapplied; thus acting to restrain the aircraft against tipping. Model 705C & 745B include a head stock that clamps to the 747 freighter/combi tail ball fitting. The head stock jaws are operated by an integral hydraulic cylinder for opening and closing the jaws around the ball fitting. The head stock jaws travel over center to the closed and lock position to ensure a positive connection even in the event of a loss of hydraulic pressure in the jaw cylinder. The stanchion cylinder assembly is supported by the tripod leg structure for towing and positioning. Once in operation, with the head stock engaged around the ball fitting, the stanchion footpad is lowered to the ground and aircraft load is transmitted through the stanchion to the single footpad. Both Malabar models meet or exceed Boeing recommendations. Specify either model for applications requiring Boeing Tool #ME65B16362.