Thought I'd drop into the bush strip at Tsek hot springs for a soak, flew the 40 minutes there only to find I'd be landing in a 10-15 mph tailwind (floatplane/helicopter guy, I read the wind from water ripples and cat paws on nearby lakes, and fluttering cottonwood leaves). Strip is 900' if you plant it real early, and has 100' trees at the end, so one way committed. My 7GCBC POH says 310' ground roll, 690' from over a 50' obstacle, so this strip is tight if on the numbers on a calm day. My decision was to turn around and go home to try it another day. Did I fold my hand too early?

Curious how the rest of the backcountry community deals with bad winds and one-way strips. Any "fudge factor" you apply to a tailwind - I've seen charts for other aircraft somewhere.

Karmutzen-You made a good decision. First, extra airspeed on top of a downwind is a really bad decision. It makes the ground speed excessive. I don't want to encourage any bad decisions so I'll explain how I would make the landing in headwind or no wind. Then the problem with that much downwind will become apparent.

I have not been there and one cannot get the feel of a place from a picture, so this is hypothetical. I would get down into low ground effect on the river. From there I would hover taxi through the cut in the trees that is at a fifteen degree angle to the runway. The fifteen degree left cross controlled rudder turn, in low ground effect over the rocks and scrub, to align with the runway is not a problem.

Knowing how it turned out in varying degrees of good conditions would be mandatory before attempting bad conditions. The problem with the big tailwind is that we would be crabbing into that wind in low ground effect. With the nose crabbed right, the left wings level rudder turn to align with the runway would now be more than fifteen degrees. The trees will block some of the tailwind, but we can't depend on that.

This is a place where landing fast over the trees and using brakes could end poorly.

We have a similar situation at Kingsley's. It used to be a fifteen degree angle through the trees, but with a half mile runway was no problem. With loaded Pawnees we took off downhill and stayed in low ground effect through the trees. Don't worry about it now. We have cleared most of the trees. Just a five degree low ground effect rudder turn will do it now. Or you can go over the trees and scare me to death.

agreed, downwind adds a lot more distance than you would think.

Best way to figure that out is go out to a strip some time and practice a few down wind landings!
Your approach is going to be quite different as your ground speed is going to be faster, so everything looks different! If you land at 50 with a 20 mph TW you are traveling 40 mph faster than landing upwind!(ground speed) Quick (So in 10 seconds how much farther did you travel at that 40 mph rate??)
Don't be afraid to land down wind, just be careful.
Keep a good grip of the stick or yoke and don't let the wind grab it out of your hand!
Note, When you get just about stopped pay attention to your elevator and rudder!! You might have to use them a bit different as they may be working in reverse or you might have to use power to make them act correctly!(as in just like taxing) You just can't hold the stick back and assume the tail is going to stay on the ground (you might have to shove it all the way forward to make it stay down!!??)(Make the wind hold the tail down!)
Keep plenty of pressure on your rudder as the wind might just snatch it away from you and slam it to one side or the other.
I think most problems on down wind landings are from not thinking about what you have to do to get stopped after you quit flying!!
Also 1 thing to be aware of in the trees is that sometimes when you get to that last 10 feet the wind is probably going to be quite different than at the top of the trees!!
Go practice, tis the only cure!!!!!

MHO and $.02
GT

Practice, practice, practice... And if your strip is one-way, I'd be really familiar with it before I attempted much of a tailwind. You need to know pretty much exactly where you can touch down and get stopped on a headwind or no-wind day, then add to that factoring in a tailwind.

Amazing how much real estate you can eat up with 15-20 KTS up the ass. And looking at trees or rocks rushing at you with only a few feet of runway left, can make you make some really poor decisions. Like try a go-around when it's not possible.

Trees with brakes locked at 20 MPH bends shit. Go-around attempt, wallowing in ground effect at 40 MPH and then hitting said trees, kills you.

Gump

We often landed at our 1600' lodge strip with a significant tailwind. Very similar setup as your picture. Not exactly one way, but required 25kts or so to drop over the trees on the high end. In that particular situation it would go from tailwind to no wind immediately below the tree line which made for a fantastic sinker. No big deal if you are ready with a handful of throttle.

Proceed with caution obviously and do what you're comfortable with. Every day is different.

GumpAir wrote:Trees with brakes locked at 20 MPH bends shit. Go-around attempt, wallowing in ground effect at 40 MPH and then hitting said trees, kills you.

This is an excellent point. Well said. Sometimes you gotta figure out how to eat a shit sandwich.

Just for the hell of it I plugged some numbers into my handy T.O.P. computer

70F with a pressure altitude of 1000 ft ( elevation of lake Lillooet surface 695 ft.)
Grass strip
0% slope
12 mph tailwind
With POH information provided.

You would become a wood chipper on take off at about 82% gross weight, assuming your 50ft obstacle is at 900ft.

Now none of this takes into account the actual horsepower your engine is developing over new, any down drafts from the trees, or any other negative conditions.

I know the T.O.P. computer is conservative, but then I have become an old pilot.

Just my $0.02 worth.

Could you get it on the strip, probably. Could you get it out, maybe.

I remember my first downwind landing some 35 years ago, at McCarran at Las Vegas, in a 182. I was shocked at how far past my planned touchdown point I actually touched down, and then how long the roll-out was, compared to my normal landings. I don't recall the tailwind exactly, but I believe it was 12-15 knots.

Since that time, I've made other landings with a tailwind, including coming into Marble last September. It wasn't much of a tailwind, just enough to raise the windsock from limp, but I touched down at least 200' or more past my usual touchdown spot. Of course, Marble is plenty long so it wasn't an issue.

But on a tight strip, where everything has to be done just right, I'd say you did exactly the right thing.

Cary

With a tailwind that strong, I would have been very inclined to follow your suit. Maybe if I really needed to go there, I'd try a dummy approach to gauge groundspeed - if I were in a powerful aircraft - but I'd hope that my better judgement would have prevailed.

Would it also make sense to be mindful of wet grass? Tailwind landing at a very short grass strip and hard braking with slick tires may not turn out so well when the grass is wet, I would think.

If brakes are a part of your plan to go in there, don't go. Cubs, champs, taylorcraft, etc. had mechanical brakes so they wouldn't be on their nose all the time. We were expected to land slow (ground speed.) We were expected to land slow whether landing upwind or downwind. How can we get slow with a tailwind? Get into ground effect before the target and use power/pitch to hover up. Or make a very steep power/pitch approach over the trees and touch down very close to the trees. Yes, you will be behind the power curve, requiring power to control the mush. The reason the airspeed indicator didn't work below 40 mph, in the old trainers, was that you weren't supposed to use it while busy landing.

So this might be helpful when running your #'s, a 10% increase in approach speed will increase your landing distance by 21%.

Now for take off with a tailwind it gets more complicated to calculate but here is the formula:
The tailwind takeoff distance is equal to 110% of the computed takeoff distance for the existing density altitude plus the value of the tailwind component divided by the rotation speed, or
110% of (D/A T/O distance)=A TW/Vr =B A+B= T/O distance.

Go out and practice on a long runway and get the feel for it.