Take-off alternate performance requirements
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Take-off alternate performance requirements
This is a planning question only! For large jets in Europe, would your take-off alternate have to comply with the ability to stop within 60 pct of the required LDA? I have checked the docs and cannot find anything to suggest otherwise.
And another thing. Take-off with eng failure. On return to dep airport SE you can only stop within 80 pct of the LDA. In the planning phase do we need to nominate a take-off alternate that complies with the 60 pct ?
And another thing. Take-off with eng failure. On return to dep airport SE you can only stop within 80 pct of the LDA. In the planning phase do we need to nominate a take-off alternate that complies with the 60 pct ?
Last edited by president; 22nd Sep 2015 at 17:06.
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According to EASA:
"The landing mass of the aeroplane determined in accordance with CAT.POL.A.105 (a)
for the estimated time of landing at the destination aerodrome and at any alternate
aerodrome shall allow a full stop landing from 50 ft above the threshold:
(1) for turbo-jet powered aeroplanes, within 60 % of the landing distance available
(LDA)"
This would imply that this planning requirement is only present for destination and any alternates. But the departure airport is neither. So to put it short any take-off alternate will comply but not the departure airport if we return immediately (as its not a destination or alternate). Right?
"The landing mass of the aeroplane determined in accordance with CAT.POL.A.105 (a)
for the estimated time of landing at the destination aerodrome and at any alternate
aerodrome shall allow a full stop landing from 50 ft above the threshold:
(1) for turbo-jet powered aeroplanes, within 60 % of the landing distance available
(LDA)"
This would imply that this planning requirement is only present for destination and any alternates. But the departure airport is neither. So to put it short any take-off alternate will comply but not the departure airport if we return immediately (as its not a destination or alternate). Right?
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It's settled that we need the performance margin for the take-off alternate. But what about return to departure airport. That's not an alternate. According to the docs I could find we don't need that margin in the planning phase (as it's not an alternate)... Question was if there is anything out there disputing that ?
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I've never heard of any requirement to assess the departure airport for LDA.
I would guess that is because in virtually every normal scenario TODR > LDR.
So, to play the devil's advocate, what about a displaced landing threshold?
I would guess that is because in virtually every normal scenario TODR > LDR.
So, to play the devil's advocate, what about a displaced landing threshold?
