ESDU 15002 defines and describes the various runway contaminants that may be encountered during aircraft operations. It also brings together information obtained from surveys of runways with hard surfaces that was included previously in ESDU 71026 and 95015, and in ESDU Technical Paper 6; these items have now been withdrawn following the publication by ESDU of improved methods for the estimation of tyre forces. The data from runway surveys are used to classify runways according to their macro-texture depth. ESDU 15002 provides examples of the macro texture depths of paved runways and the probability of encountering runways with these characteristics