In article ,
Matt Whiting wrote:
What is your threshold for landing (or departing) downwind?
Runway length.
Jim

Controllability doesn't enter into equation? It does for me.

With a 10 knot headwind, I have lots of rudder authority at 10 or 20 knots
of groundspeed on roll-out. With a 10 knot tailwind, there is no rudder
authority at 10 knots of groundspeed.

There is always the consideration of an engine failure. On takeoff or
landing, I'd prefer to be pointed into the wind if the prop stops, rather
than having to land downwind or attempt a low altitude turn into the wind...

It would depend on what aircraft type you fly. With Cessna's and
Piper's, there is no need for rudder authority below 30 knots or even
higher. I've never flown an airplane with a free castering nose wheel,
but I suspect rudder authority is more important there, however, it
still seems like the brakes would work fine for directional control at
10 knots.

My home airport (KLAM) is a one-way airport. All landings are on rw 27,
all departures are on rw 9 regardless of wind conditions. This is due to
rapidly rising terrain to the west, as well as the presence of nearby
restricted airspace and a townsite immediately to the west. Thus, I
have *lots* of experience in landing and taking off with a tailwind.
The most important thing I've learned is this: AIRSPEED AIRSPEED AIRSPEED!
Ignore how fast you *think* you're going. Ignore how fast the outside world
looks like it's going by. Pay attention to the airspeed.

Other posters are correct in that you need to turn base further out when
landing with a tailwind. How much farther out? Depends on the tailwind.
I wish there were an easy rule of thumb (like "turn base when the approach
end is 45 deg behind your wing), but there isn't.

In years of doing this, my own personal minimums (or perhaps "maximums" in
this case) are 15 kt direct tailwind. This is at an airport that sits
at 7300' MSL and has a 5300' runway, and I fly a PA32-300. If it's warm out
( 70 deg F), and the density altitude starts to creep up, that maximum will
go down.

I haven't found controlability to be much of an issue with tailwind t/o's
or landings, but then I fly a wide gear Cherokee 6. It can be with a
taildragger. The shallower climb angle is also most certainly something to
consider, especially if there are obstructions at the departure end of the
runway. Fortunately, at my home airport, the east end of the runway ends
in a serious downward cliff.

My recommendation: pay attention to the AIRSPEED! (and practice a few
tailwind landings and/or takeoffs - they're really not as terrifying
as they're made out to be).

-- Dane