J_T, OS prefers to leave tailwinds out and that is his reasonable decision - Arrrrgh!!! (Did that sound like a cry of pain?)
Actually, because resort to RDS data is of short term use when the RTOW is invalidated -
(1) Headwind is ignored in the table as it provides both D1 and G1 bonus, and
(2) Tailwind Takeoff is prohibited (because D1 is lengthened and G1 is reduced), and the opposite direction (into wind) data must be used.
That will remain the policy until we have runways significantly better even with a Down-wind than opposite direction with a Head-wind (which we do not have). If that day arrives, I'll have to produce a second table for the worst Down-wind case.
rhovsquared, Could this type of correction for RWY slope be applied under the FARs ? - Basically NO. The discussion here is centred around the Australian situation, where the Regulatory Authority provide obstacle data in the form of a series of Obstacle Clear Gradients from certain points on the runway. It is in the public domain, and available through NOTAMs. It's a good system, but does not provide discrete obstacle data, thus, the 1st Segment requires a few gymnastics. It's still light years ahead of other Regulatory Authoritys who couldn't give a damn about publishing runway obstacle data in the public domain.
FAR 25 is actually very close to it's Australian equivalent, CAO 20.7.1B, but I think that most of the points discussed here won't have much relevance even to a FAR 25 aircraft operated outside the Australian environment. The guy to whom I answer at CASA (the Regulatory Authority) likes JAR 25 (so do I), so my work ends up being one giant FAR/JAR/CAO fruit salad to keep him happy.
Beer o'clock approacheth
J_T, but the powers of darkness, otherwise known as crew scheduling, seem to have an aversion to my flying to the land of wonder, Dunnunda!
Regards,
Old Smokey