.
If required, use maximum pedal braking; and,
.
Do not stop braking until assured that the aircraft will stop within the remaining runway length.
Optimum Use of Braking Devices
Page 6
Associated Briefing Notes
The following Briefing Notes provide expanded information on landing performance and techniques:
.
8.3 - Factors Affecting Landing Distances,
.
8.5 - Landing on Wet and Contaminated Runway,
.
8.7 - Crosswind Landing.
Regulatory References
.
ICAO – Preparation of an Operations Manual (Doc 9376),
.
FAR 121.97 or 121.117 – Airports: Required Data,
.
FAR 121 Subpart I – Airplane Performance Operating Limitations:
. FAR 121.171 – Applicability,
. FAR 121.195 – Airplanes: Turbine engine-powered: Landing limitations: Destination airports,
. FAR 121.197 – Airplanes: Turbine engine-powered: Landing limitations: Alternate airports,
.
FAA – AC 916A and 91-6B,
.
JAR-OPS 1.515 – Landing – Dry Runways,
.
JAR-OPS 1.520 – Landing – Wet and Contaminated Runways,
.
UK CAA – AIC 11/98 – Landing Performance of Large Transport Aeroplanes,
.
UK CAA – AIC 61/99 – Risks and factors Associated with Operations on Runways Affected by Snow, Slush or Water.
Optimum Use of Braking Devices
Page 7
Introduction
Factors associated with landing on a wet runway or on a runway contaminated with standing water, slush, snow or ice should be assessed carefully before beginning the approach.
This Briefing Note provides an overview and discussion of operational factors involved in planning and conducting a landing on a wet or contaminated runway.
Statistical Data
Runway condition, alone or in combination with adverse crosswind, is a circumstantial factor in 75 % of runway excursions or runway overruns at landing.
Runway contamination with standing water, slush, snow or ice is a causal factor in 18 % of all landing accidents.
Defining the Runway Condition
The European JAA defines the runway condition as follows:
Dry runway:
A dry runway is “one that is neither wet nor contaminated”.
This “includes paved runways that have been specially prepared with grooved or porous pavement and maintained to retain an effectively dry braking action, even when moisture is present”.
Damp runway:
A runway is considered damp “when the surface is not dry, but when the moisture on the surface does not give a shiny appearance”.
Wet runway:
A runway is considered to be wet “when the surface is covered with water, or equivalent, not exceeding 3 mm - or when there is sufficient moisture on the runway surface to cause it to appear reflective (shiny) - but without significant areas of standing water”.
Contaminated runway:
A runway is considered to be contaminated “when more than 25 % of the runway surface (whether in isolated areas or not) -within the required length and width being used – is covered by either:
.
Standing water, more than 3 mm (1/8 inch) deep;
.
Slush (i.e., water saturated with snow) or loose snow, equivalent to 3 mm (1/8 inch) - or more -of water;
.
Snow which has been compressed into a solid mass which resists further compression and will hold together or break into lumps if picked up (i.e., compacted snow); or,
.
Ice, including wet ice contaminant (runway friction coefficient 0.05 or below)”.
