The Sikorsky (model S-64A) CH-54A/CH-54B "Skycrane", with a crew of three, was designed for heavy internal or external lift of heavy bulk loads. It had a rear-facing pilot's seat to provide a clear view of the cargo. A hoist was provided to allow pickups and deliveries without landing. A lightweight van (universal pod) could be attached to the fuselage for use as a mobile command post, maintenance and repair shop, or as a Mobile Army Surgical Hospital (MASH). The field hospital was equipped with X-Ray, lab equipment, and blood bank. It was well lighted and air conditioned so surgery could be performed where ever it was needed. A "people pod" was designed to carry 45 combat-ready troops. The "Skycrane" served with the 1st Cavalry Division in Vietnam. The CH-54 was used in aircraft recovery operations when loads were too heavy for the CH-47 Chinook. It was also useful for off-loading during ship-to-shore operations. The CH-54 could also be rigged to drop the large 10,000 lb. cratering bomb used to create landing zones ("LZs") in dense jungle. The T-54A Tarhe had a six-bladed main rotor, four-bladed metal tail rotor, was powered by two Pratt &, Whitney T73-P-1 4500 shp turbine engines, and had a speed of 128 mph (111 knots). The CH-54B was powered by two Pratt &, Whitney T73-P-700 4800 sph turbine engines.