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Old 27th May 2005 | 23:48
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Old Smokey
 
Joined: Jun 2004
Posts: 1,843
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From: Australia
Yes, that was pretty rubbery John_T, near is near, far is far (and never the twain shall meet?) The best interpretation that I've found is from a BAe P/E who specified "near" as the zone beyond the end of TODA where 1st segment ducks below the obstacle-clear gradient subtended from the end of TODA, and the actual 2nd segment gradient therefrom then intersects with the required OCG, at or before the first obstacle beyond the end of the 1st segment. Where no significant obstacle exists, this is the zone below the nominal 1.2% obstacle-clear plane subtended from the end of TODA. Anything beyond that is "far".

To add a word or two about inbuilt fat, it's appropriate that this arose in a discussion about screen heights, as this is the territory where the least fat occures. Plenty for the all engines continued Takeoff with distance to screen height increased by 15%, ever increasing obstacle clearance in the 2nd/3rd segments where the Gross Vs Net delta pads us well. A little bit of fat for the RTO with reverse thrust being a bonus, but this is gone altogether for the wet runway case, a 'fat-free' environment. The worst of all 'fat-free' environment is, of course, the OEI continued Takeoff from Vef until 2nd segment is underway, with no fat for the TODR to screen height, and no Gross Vs Net buffer in the 1st segment.

Small wonder that the most accidents occur in the 'fat-free' zone.

Audit? - So that's where you've been Mutt. Thought we'd done something to offend you.

Regards,

Old Smokey
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