Proposed amendment to Part 121 MOS to replace expiring provisions and make minor changes - some relevant to Part 135 - (CD 2522OS)

Policy Aim

The aim is to permit a flight to be planned to a destination aerodrome with a wet or contaminated runway with landing performance requirements reduced by one step. Additional safety controls would be required including the planning of a destination alternate aerodrome for the flight.

Proposed Policy

The proposed policy would permit dispatch to a destination aerodrome runway that is forecast to be wet or contaminated at a weight higher than presently permitted with the following conditions as safety controls:

• the requirement to only permit dispatch in the circumstances where the forecast indicates that the destination aerodrome may be wet or contaminated if the following conditions are satisfied:
  • the destination aerodrome landing performance for an aeroplane without AFM wet or contaminated landing performance information available is constrained to being not less than:
    • for wet runway conditions: dry LDF 1.67 (a reduction from wet LDF 1.92)
    • for contaminated runway conditions: wet LDF 1.92 (no reduction)
  • the destination aerodrome landing performance for an aeroplane with AFM wet or contaminated landing performance information available is constrained to being not less than:
    • for wet runway conditions: dry LDF 1.67 (a reduction from AFM wet x1.0 for the wet runway conditions, not less than dry LDF 1.67 where the AFM wet is greater than dry LDF 1.67), or
    • for contaminated runway conditions: AFM contaminated x1.0 for the contaminated runway conditions, not less than Dry x1.67 (a reduction from AFM contaminated x1.15, not less than AFM wet x1.0 or dry LDF 1.67)
• in both cases above, the proposed pre-flight destination aerodrome LDA requirements would be effectively ‘one-step’ less than the unvaried MOS requirements, mitigated by the additional conditions required, expressed that are:
  • a suitable destination alternate aerodrome is planned for a flight that can satisfy the unaltered MOS provisions for LDA requirements.
  • not permitted in circumstances where two destination alternate aerodromes are required for a flight.
  • not permitted at isolated destination aerodromes.