Aerodrome data and runway condition

Reference code and reference point

Planning dimensions and operational performance are different.

Code elements

The aerodrome reference code relates aerodrome characteristics to the aircraft intended to use it. The number is based on aeroplane reference field length: 1 below 800 m, 2 from 800 to below 1,200 m, 3 from 1,200 to below 1,800 m, and 4 from 1,800 m. The letter uses wingspan: A below 15 m; B 15 to below 24; C 24 to below 36; D 36 to below 52; E 52 to below 65; F 65 to below 80. The applicable standard/version also specifies how landing-gear geometry is treated.

Reference field length is a reference aircraft characteristic, not today’s required take-off distance on a hot wet runway. The aerodrome reference point is normally near the initial/planned geometric centre, established in coordination with the appropriate authority and normally remaining where first established.

Strength: identify the reporting system

In the EU Aerodromes March 2026 consolidation, bearing strength still uses ACN/PCN for pavements intended for aircraft above 5,700 kg. ACN describes the aircraft’s relative effect on a specified pavement/subgrade; PCN expresses pavement strength for unrestricted operations subject to the reported conditions. ACN not exceeding PCN is a necessary comparison under matching assumptions, alongside tyre-pressure and other limitations.

ICAO introduced ACR/PCR as the newer system; do not numerically compare an ACR to a PCN. ECQB 2026 explicitly recognises the temporary ICAO/EU difference. For aircraft of 5,700 kg or less, strength is reported by maximum allowable mass and maximum allowable tyre pressure. The operation uses the system actually published by the aerodrome.

Surface condition changes the performance decision

The code is one input; the actual contaminant and aircraft data remain essential.

Report significant conditions

Report to AIS and ATS the operationally significant condition of the movement area and related facilities: construction, damaged/uneven surfaces, contaminants, snowbanks, parked aircraft, equipment failures and other hazards. Pilots need the information before accepting a performance-dependent movement.

The runway condition report divides the runway into thirds and gives RWYCC, coverage, depth where applicable and contaminant description. Dry snow is loose and does not bind readily; wet snow can bind/compact; slush is water-saturated snow displaced by foot pressure; compacted snow, ice and wet ice have distinct braking implications. Standing water and slush also create drag and aquaplaning hazards.

RWYCC and braking

The basic scale runs from 6 (dry) through 5 (good), 4 (good to medium), 3 (medium), 2 (medium to poor), 1 (poor) to 0 (less than poor). The code is assessed under the RCAM using contaminant, temperature and other evidence and can be downgraded or upgraded under the permitted process. It is not a friction coefficient or a universal landing-distance multiplier.

Use the aircraft’s approved performance information and operator procedures, considering wind, slope, depth, coverage and each third. A pilot braking report contributes evidence; it does not automatically replace the aerodrome assessment for every subsequent aircraft.

Can you apply the rules?

Four original questions. Choose from the facts, then review the explanation.