My understanding is that the term “alternate aerodrome” in this context should cover all types, including take-off alternates and others, since it is a general requirement that the aircraft must be able to land without exceeding the MLDW at the respective aerodrome. For more specific cases, such as those in CAT.POL.A.230, the regulation explicitly states what type of alternate aerodrome is meant. Similarly, other provisions that refer to an alternate aerodrome will specify whether it is a take-off, en-route, or destination alternate. Therefore, under CAT.POL.A.225, an alternate aerodrome should be understood to include all of these.
And if we are concerned that, taking off at a weight of over 300 tons and going to the take-off alternate, we might exceed MLDW, how can that be? According to CAT.POL.A.225, it refers to CAT.POL.A.105(a), which allows the weight to be reduced by various methods, such as fuel jettisoning, etc.
As for the climb gradient requirement of a take-off alternate, it does not need to be considered in the initial dispatch. However, once you land at the take-off alternate, before departing again you must go through a new dispatch process to determine how much weight you can take off with and under what conditions. This is essentially the same as the general case: the key requirement is simply that you are able to take off from the departure aerodrome and land safely at the destination or alternates. Whether you can take off again from the alternate is another matter. In practice, though, airlines would not allow an aircraft to land at an alternate and then be stranded there because it cannot take off again.
But I’m not really sure if this is correct. Since no one else has replied to the thread, I just had to give an answer. Let’s wait for others who really know to clarify.
Last edited by Noknoipobin; 31st August 2025 at 07:48.