CAT.POL.A.335 Landing – wet and contaminated runways

WET AND CONTAMINATED RUNWAY DATA The determination of landing performance data should be based on information provided in the OM on the reported RWYCC. The RWYCC is determined by the aerodrome operator using the RCAM and associated procedures defined in Annex V (Part-ADR.OPS) to Regulation (EU) No 139/2014. The RWYCC is reported through an RCR in the SNOWTAM format in accordance with ICAO Annex 15.

LANDING ON WET GRASS RUNWAYS

(a)When landing on very short grass that is wet and with a firm subsoil, the surface may be slippery, in which case the distances may increase by as much as 60 % (1.60 factor).

(b)As it may not be possible for a pilot to determine accurately the degree of wetness of the grass, particularly when airborne, in cases of doubt, the use of the wet factor (1.15) is recommended.

DISPATCH CONSIDERATIONS FOR MARGINAL CASES The LDTA required by CAT.OP.MPA.303 may, in some cases, and in particular on wet or contaminated runways, exceeds the landing distance considered at the time of dispatch. The requirements for dispatch remain unchanged; however, when the conditions at the time of arrival are expected to be marginal, it is a good practice to carry out at the time of dispatch a preliminary calculation of the LDTA.

AFM LANDING DISTANCES FOR WET RUNWAYS Specific landing distances provided in the AFM for dispatch on wet runways, unless otherwise indicated, include a safety factor, which renders the application of the 15 % safety factor used in CAT.POL.A.335(a)(2) not necessary. This implies that the AFM distance may be presented as factored distance. When the AFM distance is not factored, a safety factor of 15 % should be applied. These distances may be longer or shorter than those resulting from CAT.POL.A.335(a)(2), but when provided, they are intended as a replacement of CAT.POL.A.335(a)(2) and it is mandatory to be used at the time of dispatch.

RUNWAYS WITH FRICTION IMPROVING CHARACTERISTICS

(a)Materials or construction techniques meant to improve the friction characteristics of a runway may be grooved runways, runways treated with PFC or other materials or techniques for which the AFM provides specific performance data.

(b)Before taking the AFM performance credit for such runways, the operator should verify that the runways intended to be operated on are maintained to the extent necessary to ensure the expected improved friction characteristics.