Common Terms and Common Terms and Definitions GroupDefinitions Group

Braking Action ReportsBraking Action Reports

Mission Statement: Develop common definitions for pilot braking reports of Good/Fair(Medium)/Poor/Nil. Develop common guidelines for flight crew assessment of braking action conditions (how to take and report)

• Pirep to be made independent of runway length, Pirep to be made independent of runway length, aircraft type, crew experienceaircraft type, crew experience

• Come up with a way to “un-nil” a runwayCome up with a way to “un-nil” a runway

• Identify criteria that describes unsafe operationsIdentify criteria that describes unsafe operations

• Standardize terminology with ICAOStandardize terminology with ICAO

COMMON TERMS and DEFINITIONS GROUP

Braking Action Braking Action TermTerm

DefinitionDefinition Aircraft Aircraft ReactionReaction

Runway Surface ConditionRunway Surface Condition ICAO ICAO CodeCode

MUMU

GoodGood

More braking capability is available More braking capability is available than is used in typical deceleration on than is used in typical deceleration on a non-limiting runway (i.e., a runway a non-limiting runway (i.e., a runway with additional stopping distance with additional stopping distance available). Directional control good.available). Directional control good.

Wet runway with a water depth of 1/8” or less Wet runway with a water depth of 1/8” or less Compacted snow with OAT below -15ºCCompacted snow with OAT below -15ºC¾” or less of dry snow¾” or less of dry snow

55 0.40 & above0.40 & above

Medium to GoodMedium to Good 44 0.36 – 0.390.36 – 0.39

MediumMedium

Noticeably degraded braking Noticeably degraded braking condition. Expect and plan for a condition. Expect and plan for a longer stopping distance such as longer stopping distance such as might be expected on a packed or might be expected on a packed or compacted snow–covered runway. compacted snow–covered runway. Effective directional control.Effective directional control.

Compacted and sanded snowCompacted and sanded snowCompacted snow with an OAT above -15ºCCompacted snow with an OAT above -15ºCSanded iceSanded ice

33 0.30 – 0.350.30 – 0.35

Medium to PoorMedium to Poor 22 0.29 – 0.260.29 – 0.26

PoorPoor

Very degraded braking condition (a Very degraded braking condition (a potential for hydroplaning). Expect potential for hydroplaning). Expect and plan for a significantly longer and plan for a significantly longer stopping distance such as might be stopping distance such as might be expected on an ice-covered runway. expected on an ice-covered runway. Directional control minimally Directional control minimally effective.effective.

Wet snowWet snowSlushSlushWet runway with a water depth more than 1/8” Wet runway with a water depth more than 1/8” Heavy rainHeavy rainIceIce

11 0.25 & below0.25 & below

NilNilBraking action is minimal to non-Braking action is minimal to non-existent and/or directional control existent and/or directional control uncertain.uncertain.

Wet IceWet Ice

Proposed Metrics for Pilot Proposed Metrics for Pilot ObservationsObservations

• Thrust Reverser UseThrust Reverser Use

• Directional Control Directional Control

• Anti Skid cyclingAnti Skid cycling

• Brake pedal force usedBrake pedal force used

• Deceleration rateDeceleration rate

• Referenced “turn off” pointReferenced “turn off” point

• Auto Brake SettingAuto Brake Setting

““Nil”Nil”Draft Pilot Reporting CriteriaDraft Pilot Reporting Criteria

• (Max) Thrust reverser utilized until (Max) Thrust reverser utilized until stop. Directional control dependant stop. Directional control dependant on aerodynamic forces only on aerodynamic forces only (modulated TR use). Poor directional (modulated TR use). Poor directional control even while taxiing. Full brake control even while taxiing. Full brake application with little or no effect. application with little or no effect. (Full anti-skid cycling throughout (Full anti-skid cycling throughout rollout.) rollout.)

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