Complex sentence: The mammoth eight-engine design was intended for use as a military transport, with a large bow door admitting vehicles and bulky freight to the upper deck, and also as a long-range bomber, flying tanker, aerial minelayer and U-boat supply vessel.
Split into simpler sentences: The mammoth eight-engine design was intended for use as a military transport, with a large bow door admitting vehicles and bulky freight to the upper deck. It was also designed for use as a long-range bomber, flying tanker, aerial minelayer and U-boat supply vessel.