PPRuNe Forums - View Single Post - Takeoff performance - Intersection vs full length.
Old 30th Nov 2016, 15:03
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Tu.114
 
Join Date: Feb 2009
Location: Austria
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Which limit will come to bite You when You use an intersection with more runway length available than the one You calculated?

- TORA/TODA? No, because You have more runway ahead of You than You calculated for.

- ASDA? Neither, because You have calculated the speeds for a shorter runway and should therefore come to a halt at a distance from the far threshold equal to the additional distance You gained from the non-intersection T/O in case of a rejected takeoff.

- Climb gradient? Neither, as You rotate and lift off earlier on the runway than You calculated, thereby increasing the distance from the obstacles.

- Brake energy? No, as You are still using the same V speeds as You calculated for the more limiting intersection.

- Vmc, Tire speed? no, not really.

So: if You have calculated Your performance for a more limiting intersection than the one You actually use, You should be good to go. However, You may be missing the opportunity to use a higher derate/flex or whatever a reduced power takeoff is called on Your type.
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