Excerpts from the report: During a 2-year period, 30 shipping tests were conducted to develop a loading pattern that would give adequate air circulation in different types of trailers. Load stability, air circulation, cooling rates, temperature maintenance, and commodity and container damage were studied. In some of the development work, researchers rode inside loaded trailers to measure air velocities and observe characteristics of the tight-stack pattern and other loading patterns in both refrigerated and ventilated loads. Air movement was measured by hot-wire and vane-type anemometers, and product and air temperatures were measured with thermocouples and stick thermometers. The patterns studied were (1) chimney stack, (2) crosswise offset by layers, (3) alternate layers six and seven wide, (4) spaced vertical columns, and (5) spaced bonded-block.
