I think that
Flight Safety got it right, it's a weed-out question at interview. I was curious why
Mutt and
John_Tullamarine didn't take a bight at this one, they typically would, but methinks that they saw what
Flight Safety saw. Of course, Mr. Gullible (ME) was "In like Flynn". I should have stuck to my original post in this thread (#7) where I said that neither option was acceptable. Such is life.
oldebloke, from one oldie to another, I don't have an aversion to Wet runway data at all, in fact it's essential. What does concern me significantly is the criteria used in determining the data. I've done a lot of flight testing, including RTOs at limiting conditions, and to put it lightly, they're a close run thing. Statictically the RTO produces a far greater number of accidents and serious incidents than does the continued Takeoff case. It's not just a statistical thing, there are very generous performance margins provided for the continued Takeoff case, but precious little for the RTO, and therein lies the root cause of the statistics. The only bonus is that, for dry runways, we have no accounting for reverse thrust. Many pilots place great stock in this, all the roaring and snorting of full reverse seems impressive, but in terms of Accelerate-Stop distance reduction, the bonus is very small, but nevertheless a bonus. The certification for the wet runway consumes in it's entirety the only bonus that we ordinarily have (reverse thrust), leaving us
NOTHING. As for the 15 ft screen height, NO, I don't think that it is nearly enough. I know that the 35 ft screen height is simply an arbitrary 'line in the sand' (as
John_Tullamarine would put it), but not too bad a 'line in the sand' at that. One regulatory authority to which I prepared and submitted performance data point blank refused to accept the 15 ft data (although legal) insisting upon 35 ft on all occasions. It was the happiest refusal of my career, I relished the additional work to re-do the performance data for 35 ft, with the Regulatory Authority to hold up to the company as the 'bad guys', not me.
What really bugs me is when the F/O pulls out the wet runway data for a runway that could only be described as a bit damp. Good manners prevail, but I'm sorely tempted to say "What? You want to take away the only margin that I have?"
Just my thoughts, and as for the Singapore wet runway situation, I would say that we have less wet runway "time' here than elsewhere. It comes down in buckets, makes our runways very wet for an hour or so, and goes away. In some places it just rains aaaallll day
Rant over,
Regards,
Old Smokey