GM1 CAT.POL.A.330 & CAT.POL.A.335 Landing -- dry runways & Landing -- wet and contaminated runways

• ED Decision 2021/005/R found in: Air Operations (965/2012) Part-ARO Part-ORO Part-CAT Part-SPA Part-NCC Part-NCO Part-SPO (Sep 2023)

GM1 CAT.POL.A.330 & CAT.POL.A.335 Landing — dry runways & Landing — wet and contaminated runways ED Decision 2021/005/R LANDING DISTANCES AND CORRECTIVE FACTORS The AFM provides performance data for the landing distance under conditions defined in the applicable certification standards. This distance, commonly referred to as the ALD, is the distance from the position on the runway of the screen height to the point where the aeroplane comes to a full stop on a dry runway. The determination of the ALD is based on the assumption that the landing is performed in accordance with the conditions and the procedures set out in the AFM on the basis of the applicable certification standards. As a matter of fact, any particular landing may be different from the landing technique that is assumed in the AFM for certification purposes. The aircraft may approach the runway faster and/or higher than assumed; the aircraft may touch down further along the runway than the optimum point; the actual winds and other weather factors may be different from those assumed in the calculation of the ALD; and maximum braking may not be always achievable. For this reason, the LDA is required by [CAT.POL.A.330](#_DxCrossRefBm318086301) and [CAT.POL.A.335](#_DxCrossRefBm318086300) to be longer than the ALD. The margins by which the LDA shall exceed the ALD on dry runways, in accordance with CAT.POL.A.330, are shown in the following Table 1. Table 1: Corrective factors for dry runways <table border="1" cellpadding="0" cellspacing="0"><tr><td valign="top" width="200"><p><b>Aeroplane category</b></p></td><td valign="top" width="200"><p><b>Required Margin (dry runway)</b></p></td><td valign="top" width="200"><p><b>Resulting factor (dry runway)</b></p></td></tr><tr><td valign="top" width="200"><p><b>All aeroplanes</b></p></td><td valign="top" width="200"><p>ALD &lt; 70 % of the LDA</p></td><td valign="top" width="200"><p>LDA = at least 1.43 x ALD</p></td></tr><tr><td valign="top" width="200"><p><b>Aeroplanes approved under CAT.POL.A.355</b></p></td><td valign="top" width="200"><p>ALD &lt; 80 % of the LDA</p></td><td valign="top" width="200"><p>LDA = at least 1.25 x ALD</p></td></tr></table> If the runway is wet and the AFM does not provide specific performance data for dispatch on wet runways, a further increase of 15 % of the landing distance on dry runways has to be applied, in accordance with CAT.POL.A.335, as shown in the following Table 2: Table 2: Corrective factors for wet runways <table border="1" cellpadding="0" cellspacing="0" width="603"><tr><td valign="top" width="200"><p><b>Aeroplane category</b></p></td><td valign="top" width="403"><p><b>Resulting factor (dry runway)</b></p></td></tr><tr><td valign="top" width="200"><p><b>All aeroplanes</b></p></td><td valign="top" width="403"><p>LDA = at least 1.15 x 1.43 x ALD = 1.64 x ALD</p></td></tr><tr><td valign="top" width="200"><p><b>Aeroplanes approved under CAT.POL.A.355</b></p></td><td valign="top" width="403"><p>LDA = at least 1.15 x 1.25 X ALD = 1.44 x ALD</p></td></tr></table> However, for aeroplanes approved under [CAT.POL.A.355](#_DxCrossRefBm318086423), when landing on wet runways, CAT.POL.A.355 further requires the flight crew to apply the longer of the landing distance resulting from the above table and the landing distance resulting from the application of [CAT.OP.MPA.303(b)](#_DxCrossRefBm318086297).). If performance information for the assessment of LDTA is not available as per CAT.OP.MPA.303(b)(2), the required landing distance on wet runways should be at least: 1.15 x 1.67 x ALD for turbojet-powered aircraft and 1.15 x 1.43 x ALD for turbopropeller-powered aircraft. GM1 CAT.POL.A.330 & CAT.POL.A.335 Landing — dry runways & Landing — wet and contaminated runways ED Decision 2021/005/R LANDING DISTANCES AND CORRECTIVE FACTORS The AFM provides performance data for the landing distance under conditions defined in the applicable certification standards. This distance, commonly referred to as the ALD, is the distance from the position on the runway of the screen height to the point where the aeroplane comes to a full stop on a dry runway. The determination of the ALD is based on the assumption that the landing is performed in accordance with the conditions and the procedures set out in the AFM on the basis of the applicable certification standards. As a matter of fact, any particular landing may be different from the landing technique that is assumed in the AFM for certification purposes. The aircraft may approach the runway faster and/or higher than assumed; the aircraft may touch down further along the runway than the optimum point; the actual winds and other weather factors may be different from those assumed in the calculation of the ALD; and maximum braking may not be always achievable. For this reason, the LDA is required by [CAT.POL.A.330](#_DxCrossRefBm927678681) and [CAT.POL.A.335](#_DxCrossRefBm927678680) to be longer than the ALD. The margins by which the LDA shall exceed the ALD on dry runways, in accordance with CAT.POL.A.330, are shown in the following Table 1. Table 1: Corrective factors for dry runways <table border="1" cellpadding="0" cellspacing="0"><tr><td valign="top" width="200"><p><b>Aeroplane category</b></p></td><td valign="top" width="200"><p><b>Required Margin (dry runway)</b></p></td><td valign="top" width="200"><p><b>Resulting factor (dry runway)</b></p></td></tr><tr><td valign="top" width="200"><p><b>All aeroplanes</b></p></td><td valign="top" width="200"><p>ALD &lt; 70 % of the LDA</p></td><td valign="top" width="200"><p>LDA = at least 1.43 x ALD</p></td></tr><tr><td valign="top" width="200"><p><b>Aeroplanes approved under CAT.POL.A.355</b></p></td><td valign="top" width="200"><p>ALD &lt; 80 % of the LDA</p></td><td valign="top" width="200"><p>LDA = at least 1.25 x ALD</p></td></tr></table> If the runway is wet and the AFM does not provide specific performance data for dispatch on wet runways, a further increase of 15 % of the landing distance on dry runways has to be applied, in accordance with CAT.POL.A.335, as shown in the following Table 2: Table 2: Corrective factors for wet runways <table border="1" cellpadding="0" cellspacing="0" width="603"><tr><td valign="top" width="200"><p><b>Aeroplane category</b></p></td><td valign="top" width="403"><p><b>Resulting factor (dry runway)</b></p></td></tr><tr><td valign="top" width="200"><p><b>All aeroplanes</b></p></td><td valign="top" width="403"><p>LDA = at least 1.15 x 1.43 x ALD = 1.64 x ALD</p></td></tr><tr><td valign="top" width="200"><p><b>Aeroplanes approved under CAT.POL.A.355</b></p></td><td valign="top" width="403"><p>LDA = at least 1.15 x 1.25 X ALD = 1.44 x ALD</p></td></tr></table> However, for aeroplanes approved under [CAT.POL.A.355](#_DxCrossRefBm927678803), when landing on wet runways, CAT.POL.A.355 further requires the flight crew to apply the longer of the landing distance resulting from the above table and the landing distance resulting from the application of [CAT.OP.MPA.303(b)](#_DxCrossRefBm927678677).). If performance information for the assessment of LDTA is not available as per CAT.OP.MPA.303(b)(2), the required landing distance on wet runways should be at least: 1.15 x 1.67 x ALD for turbojet-powered aircraft and 1.15 x 1.43 x ALD for turbopropeller-powered aircraft. ##### GM1 CAT.POL.A.330 & CAT.POL.A.335 Landing — dry runways & Landing — wet and contaminated runways *ED Decision 2021/005/R* **LANDING DISTANCES AND CORRECTIVE FACTORS** The AFM provides performance data for the landing distance under conditions defined in the applicable certification standards. This distance, commonly referred to as the ALD, is the distance from the position on the runway of the screen height to the point where the aeroplane comes to a full stop on a dry runway. The determination of the ALD is based on the assumption that the landing is performed in accordance with the conditions and the procedures set out in the AFM on the basis of the applicable certification standards. As a matter of fact, any particular landing may be different from the landing technique that is assumed in the AFM for certification purposes. The aircraft may approach the runway faster and/or higher than assumed; the aircraft may touch down further along the runway than the optimum point; the actual winds and other weather factors may be different from those assumed in the calculation of the ALD; and maximum braking may not be always achievable. For this reason, the LDA is required by [CAT.POL.A.330](#_DxCrossRefBm523088237) and [CAT.POL.A.335](#_DxCrossRefBm523088236) to be longer than the ALD. The margins by which the LDA shall exceed the ALD on dry runways, in accordance with CAT.POL.A.330, are shown in the following Table 1. **Table 1: Corrective factors for dry runways** <table bgcolor="#d9d9d9" cellpadding="7" cellspacing="0"> <col/> <col/> <col/> <tr valign="top"> <td bgcolor="#808080"><p> <b>Aeroplane category</b></p> </td> <td bgcolor="#808080"><p> <b>Required Margin (dry runway)</b></p> </td> <td bgcolor="#808080"><p> <b>Resulting factor (dry runway)</b></p> </td> </tr> <tr valign="top"> <td bgcolor="#808080"><p> <b>All aeroplanes</b></p> </td> <td bgcolor="#d9d9d9"><p> ALD &lt; 70 % of the LDA</p> </td> <td bgcolor="#d9d9d9"><p> LDA = at least 1.43 x ALD</p> </td> </tr> <tr valign="top"> <td bgcolor="#808080"><p> <b>Aeroplanes approved under CAT.POL.A.355</b></p> </td> <td bgcolor="#d9d9d9"><p> ALD &lt; 80 % of the LDA</p> </td> <td bgcolor="#d9d9d9"><p> LDA = at least 1.25 x ALD</p> </td> </tr> </table> If the runway is wet and the AFM does not provide specific performance data for dispatch on wet runways, a further increase of 15 % of the landing distance on dry runways has to be applied, in accordance with CAT.POL.A.335, as shown in the following Table 2: **Table 2: Corrective factors for wet runways** <table bgcolor="#d9d9d9" cellpadding="7" cellspacing="0"> <col/> <col/> <tr valign="top"> <td bgcolor="#808080"><p> <b>Aeroplane category</b></p> </td> <td bgcolor="#808080"><p> <b>Resulting factor (dry runway)</b></p> </td> </tr> <tr valign="top"> <td bgcolor="#808080"><p> <b>All aeroplanes</b></p> </td> <td bgcolor="#d9d9d9"><p> LDA = at least 1.15 x 1.43 x ALD = 1.64 x ALD</p> </td> </tr> <tr valign="top"> <td bgcolor="#808080"><p> <b>Aeroplanes approved under CAT.POL.A.355</b></p> </td> <td bgcolor="#d9d9d9"><p> LDA = at least 1.15 x 1.25 X ALD = 1.44 x ALD</p> </td> </tr> </table> However, for aeroplanes approved under [CAT.POL.A.355](#_DxCrossRefBm523088359), when landing on wet runways, CAT.POL.A.355 further requires the flight crew to apply the longer of the landing distance resulting from the above table and the landing distance resulting from the application of [CAT.OP.MPA.303(b)](#_DxCrossRefBm523088233).). If performance information for the assessment of LDTA is not available as per CAT.OP.MPA.303(b)(2), the required landing distance on wet runways should be at least: 1.15 x 1.67 x ALD for turbojet-powered aircraft and 1.15 x 1.43 x ALD for turbopropeller-powered aircraft.