Each time planes land on the airfield, the wheels leave rubber and skid on the runway surface. Over time, the rubber creates a buildup, eventually filling grooves that drain water from the runway, which is unsafe if not removed. According to research by government entities including NASA, the FAA and United States Air Force, not removing rubber from runway surfaces may lead to hydroplaning and poor braking performance from aircraft.
“The rubber also can become tacky and even oily, depending on the temperature,” said Philadelphia International Airport (PHL) Pavement and Grounds Department (P&G) Superintendent Anthony Alfonse. “So, the rubber is removed to keep drainage grooves clear and to make sure the surface is not slippery and safe for aircraft to use.”
Every fall and spring, PHL's P&G team undertakes a project to remove rubber deposits and buildup from the runway surfaces for the safety of its passengers and stakeholders. P&G collaborates with PHL’s Facilities Department and Facilities Maintenance contractor to bring in a rubber removal contractor with a specialty large semi-truck and a friction tester known as the Douglas Mu-Meter Mk6. Once the contractor is scheduled, P&G and the Airport Operations Department inspect and identify the runways to be addressed, surveying, measuring, and marking the areas that need to be cleaned. Since the friction equipment does not include a wash unit, friction tests are done during precipitation.
To decrease the impact on airport operations, work is scheduled for overnight. The vehicle moves slowly and usually runs six-to-eight-hours per night. This fall, the main arrival points on PHL’s two main runways, Runway 27R and Runway 27L, had a combined total of 258,300 square feet of rubber removed.
Watch a video of the rubber removal process below: