Airfield rubber removal
Airfield rubber removal, also known as runway rubber removal, is the use of high pressure water, abrasives, chemicals and other mechanical means to remove the rubber from tires that builds up on airport runways. In the United States, the Federal Aviation Administration (FAA) specifies friction levels for safe operation of planes and measures friction coefficients for the evaluation of appropriate friction levels. Individual airports incorporate rubber removal into their maintenance schedules based on the number of take offs and landings that each airport experiences. Source of airfield rubber build-up When a plane lands, the tires are not spinning. The time it takes for the tires to get up to speed is referred to as "spin up time" (Speidel, 2002). During this time the tires are effectively dragging on the runway as well as being put under pressure by the weight of the airplane. This can be seen in the slight puff of smoke that comes from a landing aircraft's tires as they first touch the runway surface. The friction built up causes the rubber to polymerize and harden to the runway surface. Effects of rubber buildup The buildup of rubber affects the level of friction of the runway, most noticeably