Request Reprint Send us your request to reprint copyrighted material. Currently, cars are designed based on certain Detroit traditions or icons. Another tradition is that the front wheel wells cannot be covered, even though wind tunnel tests have shown that covers greatly reduce the energy required per mile.
Materials are another Detroit tradition.
Cars are built mostly of steel, cast iron and glass, which are three of the heaviest available materials. Until the government forced the use of seat belts, the only crash safety feature that Detroit offered was size. However, the crash survival advantage of large vehicles, which shows up in injury statistics, is relative, not absolute. In other words, the people in the larger of two vehicles involved in a collision sustain fewer injuries. Crash survivability was researched by the military after World War II, and has been designed into aircraft for the past 40 years.