AMC1 CAT.OP.MPA.303(e) In-flight check of the landing distance at time of arrival — aeroplanes
CAA ORS9 Decision No. 15
PERFORMANCE INFORMATION FOR THE ASSESSMENT OF THE LDTA — APPROVED DATA
Approved data for the assessment of the LDTA contained in the AFM should be developed in accordance with AMC 25.1592, or equivalent.
PERFORMANCE INFORMATION FOR THE ASSESSMENT OF THE LDTA — SUPPLEMENTARY DATA
When approved data for the assessment of the LDTA contained in the AFM is insufficient, the content of the AFM should be supplemented with one of the following sets of data, provided by the aircraft manufacturer or the type certificate holder (TCH) or an organisation approved under Part 21 and having the relevant privileges within the scope of its organisation approval:
(a) Data for the assessment of the LDTA produced for aeroplanes not having CS 25.1592 or equivalent in their certification basis. Such data may be presented in terms of runway surface conditions, pilot-reported braking actions, or both, and should include at least:
(1) an operational airborne distance;
(2) the range of braking actions as related to the RWYCC;
(3) the effect of speed increments over threshold;
(4) the effect of temperature; and
(5) the effect of runway slope.
When data is provided only in terms of pilot-reported braking actions, instructions should be provided on how to use such data to carry out an assessment of the LDTA in terms of a runway surface condition description.
(b) Data developed in accordance with FAA AC 25-32.
(c) Data for wet runways corrected to meet the criteria of LDTA, as listed under point (a), in accordance with a methodology provided by the aircraft manufacturer or the type certificate holder (TCH) or an organisation approved under Part 21 and having the relevant privileges in the scope of its organisation approval.
(d) Data for contaminated runways developed in compliance with CS 25.1591 or equivalent, which were in use before the implementation of the LDTA, and are corrected to meet the criteria of the LDTA, as listed under point (a), in accordance with a methodology provided by the aircraft manufacturer or the TCH or an organisation approved under Part 21 and having the relevant privileges within the scope of its organisation approval.
PERFORMANCE INFORMATION FOR THE ASSESSMENT OF THE LDTA — DATA DETERMINED BY EASA
When there is no data available for the assessment of the LDTA, performance information for the assessment of the LDTA may be determined by applying the following method:
(a) Correction factors may be applied to the certified landing distances on dry runway published in the AFM for turbojet-powered aeroplanes and turbopropeller-powered aeroplanes.
(b) For this purpose, the landing distance factors (LDFs) from Table 1 below may be used:
| Runway condition code (RWYCC) | 6 | 5 | 4 | 3 | 2 | 1 |
|---|---|---|---|---|---|---|
| Runway descriptors | Note 1 | Note 1 | Note 1 | Note 1 | Note 1 | Note 1 |
| Turbojet without reverse | 1.67 | 2.6 | 2.6 | 3.2 | 4.0 | 5.1 |
| Turbojet with all reversers operating | 1.67 | 2.2 | 2.3 | 2.5 | 2.9 | 3.4 |
| Turboprop (see Note 2) | 1.67 | 2.0 | 2.2 | 2.4 | 2.7 | 2.9 |
Note 1: Runway descriptors may be found in the RCAM for each RWYCC or braking action.
Note 2: These LDFs apply only to modern turboprops with efficient disking drag. For older turboprops without adequate disking drag, use the LDFs for turbojet without reverse.
Note 3: The LDFs can apply to any type of anti-skid system, i.e. fully-modulating, quasimodulating or on-off system.
(1) To find the LDTA, multiply the AFM (dry, unfactored) landing distance by the applicable LDFs from Table 1 above for the runway conditions existing at the time of arrival. If the AFM landing distances are presented as factored landing distances, then that data needs to be adjusted to remove the applicable dispatch factors applied to that data before the LDFs from Table 1 above are applied.
Note 1: Dispatch factors that are sometimes applied in AFMs to landing distances in order to provide factored distances to operators are not intended to be cumulated with the LDFs for the calculation of the LDTA.
(2) The LDFs given in Table 1 above include a 15 % safety margin and an air distance representative of normal operational practices. They account for variations of temperature up to international standard atmosphere (ISA) + 20 °C, runway slopes between –2 % and +2 %, and an average approach speed increment of 5 up to 20 kt. They may not be conservative for all configurations in case of unfavourable combinations of these parameters.