The majority of the responses that I have seen have concentrated on what
happens AFTER the wheels touch the runway. You also have to consider the
glideslope with a headwind vs a tailwind -- and obstacle clearance. Runway
slope has no effect on the flight path!

The penalty for misjudging a tailwind approach can be horrendous, as much
more runway distance can be consumed in the air than can be regained by an
uphill slope after touchdown. For winds in excess of 10 knots, runway slope
has little bearing (with the exception of some truly horrific slopes on some
pathalogical 1-way mopuntain strips.


On 9 Oct 2006 13:02:24 -0700, "Tony Cox" wrote:

Here's a problem which seems to have a non-trivial solution.
At least, I've not been able to find a definitive answer to it, but
what do I know??

Suppose one wishes to land at an airport with a runway
that slopes at X degrees. The wind -- assumed to be directly
aligned with the runway -- is Y knots from the "high" end of
the runway.

Clearly, if Y is positive, one should try to land in the
"up-slope" direction to minimize one's ground roll. One
will be landing "up" and into a headwind. But what if
Y is negative? Clearly, if Y is just a few knots neg, one would
still land "up-slope", because the braking effect of rolling
out up-hill more than compensates for the higher landing
speed due to the tail wind.

If Y is negative and more substantial, which way should
one land? At some point, it makes sense to switch to the
other end of the runway -- landing downhill -- to take advantage
of the (now) headwind. But how does one establish which way
to land, assuming no clues from other traffic in the pattern? The
aim is to select a direction, given X and Y, which would result
in the smaller ground roll.

Rule of thumb responses are interesting, but better would be
a full mathematical treatment. Presumably, a proper treatment
would need to include touch-down speed too, and perhaps
gross weight as well.

Its more than an academic question for me. My home airport
has a 3 degree runway, and some local airports are even
steeper.