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Drainage and Maintenance

            A large part of the problem of early travel was that, when runways are in an environment where precipitation in any form was present, there was high risk of bad landings due to slippery conditions. In the late 1960s, NASA conducted several experiments at Langley Research Center. The experiments were concluded in the early 1980s and ended with NASA, Langley, and the FAA technical center showing that cutting small transverse lines (close packed) along the length of the runway would greatly increase the amount of friction. This would cause planes to stop in a lesser amount of space, as well as provide small channels where water could flow more easily to the edges of the runway, instead of building up in puddles before runoff occurs. Wilbur Thomas, a former commercial airline pilot and friend told me, “The hatched runways provide excellent support in helping to stop the plane after landing, but on the other hand, it makes takeoffs more difficult because it is harder to get up to speed.” Another way to provide safer stopping conditions and drainage is to wire comb concrete pavements. This has very much the same effect as installing close-packed grooves.

            When considering the maintenance of an airport runway and the surrounding taxiways, it is important to note the ways that any type of pavement can be affected, such as type and frequency of planes coming and going, and environmental strains. Also it should be taken into account that different types of buildup on the runway can cause potentially harmful outcomes. Some types of buildup are: rubber from tires, dust, jet fuel, oil, and any other non-natural additive that could potentially take a fraction of the friction away. It is important to note that if buildup of rubber occurs, chemicals of any type must not be used on concrete runways. Any additional chemicals that are used could potentially break down the chemical bonds that are present in the concrete. Most often it is adequate to use a portable pressure washer to remove buildup.