Soldier-Machine Performance Field Trials - Ammunition Loading of the Palletized Loading System

The Combat Service Support Division of the U.S. Army Human Engineering Laboratory conducted a series of field trials uploading ammunition onto a surrogate of the Army's latest generation of tactical transport, the Palletized Loading System (PLS), a 15-ton payload capacity truck equipped with a demountable flatrack instead of a conventional fixed bed. Twelve recent graduates from the advanced individual training course for ammunition handlers (military occupational speciality 55B) were tasked to load and secure PLS flatracks, both grounded and on board PLS trucks, with pallets of ammunition. Two types of typical high usage ammunition were chosen, 155mm artillery projectiles and 105mm tank cartridges for armored units. Each of the ammunition types was further subdivided as uniform loads where the flatracks are loaded with identical pallets of one commodity and Unit Configured Loads (UCLs), a mix of projectiles and propellant charges for the artillery loads, and a mix of 105mm cartridges and small arms ammunition for the armor loads. The experimental results and subsequent comparative statistical analysis showed that (a) loading and securing grounded flatracks was faster than loading on board trucks and (b) armor ammunition loads took less time than artillery ammunition loads. There were no differences in the total times for UCL versus uniform loads; however, the time to secure an artillery UCL was greater than for the uniform load, probably because a more difficult tie-down routine with more tie-down straps was being used.