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XCH-62 Heavy Lift Helicopter [HLH] MILVAN Containers

In 1969 the Army requirements for a Heavy Lift Helicopter specified one that could lift a 23-ton payload at 4,000 feet altitude, 95F temperature, hover out of ground effect, 500 feet per minute rate of clime, and the ability to transport the load 100 nautical miles. These requirements were developed from a study which shows that to have a 95 percent probability of mission success a helicopter must be capable of lifting its designed payload under these environmental conditions, and in a hover out-of-ground effect. The payload requirement was based upon the Army's need to lift the following item of easentisl equipment: maximum loaded MILVAN container (22.4 tons), mechanized infantry combat vehicle (22 tons), self-propelled medium artillery (22.5 tons), bridging (20 tons), dozer (23 tons), air defense artillery (19-20 tons), and mobile supply vehicle (20-21 tons).

The Army subsequently received DOD and Congressional approval for an alternate helicopter design with a 22.5 ton payload at sea level, 95'F temperature, hover out-of-ground effect. At 4,000 feet altitude, 95F temperature, hover out-of-ground effect, the Army estimated the lift capability of the HLH to be approxtiately 19.2 tons. If this capability was realized thr Army believed in 1973 that the HLH would be capable of lifting the essential tactical equipment enumerated above by reducing the amount of fuel carried and the mission range. The helicopter's lift capability would be influenced by atmospheric and other factors. Thus, just as it estimated a 19.2.ton lift capability for the shore based missions, so did the Army estimate that given the operating conditions of sea level, 90°F, hover in-ground effect, the HLH would be able to lift containerized and other cargo weighing up to 33.6 tons.

The HLH design point was fixed at 22.5 tons so that it could handle cargo transported in containers which have a gross maximum capacity of 22.4 tons. This is the capacity of the MILVAN container, of which the Amy owned 6,700 in 1973. But by far the larger portion of the DOD's containerized shipments overseas were made under contract with commercial haulers. The 20-foot commercial container has the same 22.4.ton capacity as the MILVAN. The larger commercial containers have greater capacity. The larger containers accounted for more than 70 percent of the cargo moved. The HLH was expected to lift one of the larger-sized containers too, depending on thetr cargo-laden gross wedght.

Prior to the 1970s most shipments had been by conventional breakbulk fleet. Breakbulk ships were slated to be replaced by a fleet featuring a containerized shipment system so that the percentage of containerized cargo outbound from the United States was expected by the Amy to increase by 1975 from 50 percent to about 75 percent of all cargo shipped. It was estimated by the Amy that in a combat environment ammunition represented about 60 percent (by weight) of the dry bulk cargo that would be shipped to a theater. The shipment of ammunition in the continental United States involved certain safety and security risks and was one reason why containers had rarely been used up to the early 1970s for this purpose. The Army was trying to resolve these problems so that it would be able to use containers for ammunition shipments.

The Army, in testimony before congressional committees, had stated that the Heavy Lift Helicopter's greatest impact on the operations of all types of maneuver forces would be its ability to lift the fully loaded MILVAN container in ship-to-shore and aerial port clearance movements. Army testimony was intended to cover not only the MILVANs but also the more frequently used standard commercial containers. The majority of cargo shipped overseas was loaded into 35- and 40-foot containers.

At sea level the HLH would be capable of lifting all of the larger containers loaded up to 22.5 tons and under certain conditions, some whose gross weight was higher. Although the larger containers carry most of the military cargo shipped overseas, the HLH design point of 22,5 tons was based on the proposed use of the 20-foot container loaded to its gross 22.4.ton weight. The Army statistics showed that the HLH would have been capable of lifting virtually all shipments in 20-foot containers made from the Continental United States during the fiscal year 1972.

Amy officials also stated in testimony that there were three categories of items that would fill a MILVAN container to its maximum gross weight -- ammunition, spare parts and items such as engineering barrier materiel. Due to constraints on the transporting of ammunition, MILVAN containers had rarely been used to ship this item. The Army expected the use of MILVANs for ammunition shipments to increase as a result of progress made towards resolving several of the attendant problems. It was trying to resolve problems connected with the use of commercfal containers for ammunition shipments so that these, too, could be used for this purpose.

Three factors which had limited the use of MILVANs and commercial containers for ammunition shipments were (1) the difficulty of achieving economic cube utilization with ammunition-laden MILVANs, (2) problems with safety and security, and (3) the limited number of available ammunition ports which could handle these shipments.

The Army, in an Ammunition Container Criteria Study, found that then-current ammunitiona pallet configurations were such that the utilization of the M.1 MILVAN payload capacity of 22.4 tons was impracticable, except for the most dense items such as bombs and large caliber projectiles. Cube utilization is particularly important in moving any cargo overseas in containers since both port handling and trans-oceanic line-haul costs are based on volume rather than weight. Significant economic penalties are incurred when container cube is poorly utilized. As of early 1973 the Army was revising its ammunition pallet configuration to permit better utilization of the full 20-foot container capacity of 22.4 tons.

The use of containers for the shipment of smmunition had also been limited by safety and security factors which required placing restrictions on transporting smmunition over highways and rail lines. Storage loading and movement of emmunitfon is closely regulated by various agencies including DOD, the Departient of Transportation, the Coast Guard, and the Bureau of Explosives.The safety questions had been resolved to the extent that MILVAN containers were certified by the Department of Transportation in February 1973 for the shipment of munition for a period of one year. The Army was trying to resolve problems connected with the shipment of munition in commercial containers so that these, too, could be utilized for this purpose.

Most ports had only a limited capability for handling the shipment of containerized ammunition. The port facilities were being upgraded so that more will be able to handle containerized shipments.



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Page last modified: 07-07-2011 02:32:47 ZULU