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On runway like the one in Courchevel Altiport, how difficult is it to land? what is diffirent in the aircraft landing configuration when landing on an upslope runway vs normal runway?

EDIT:

Thanks for the answers guys, I didn't know that the airport had a level "touch down" point. still I am curious what should a pilot do (regarding air speed, pitch, flaps ...) if the runway itself was 10% upward (no level parts)... would the plane be in a "climbing-like" configuration? what about speed?

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  • $\begingroup$ This video shows that the approach end is relatively flat and its only the middle part that is at a slope. The approach is probably pretty much the same, except you can't go around so you have to stick it the first time. $\endgroup$ – Ron Beyer Oct 26 '16 at 13:50
  • $\begingroup$ Actually regarding *takeoff guys, at Courchevel do you go up or downhill, or are both possible? In theory is it easier or is it harder to take off if the runway slopes down versus normal flat takeoff runway? What about one that slopes up versus normal flat takeoff runway? $\endgroup$ – Fattie Oct 26 '16 at 18:32
  • $\begingroup$ @JoeBlow In the case of Courchevel and Tenzing-Hillary in Nepal, take-offs and landings are only allowed in a certain direction. Take a look at this video to see what the pilot see's. Imagine trying to take-off uphill, not only do you have the slope of the runway to deal with, but the unforgiving mountain behind it. It is always harder to take off uphill and easier to land uphill. $\endgroup$ – Ron Beyer Oct 26 '16 at 19:27
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    $\begingroup$ Please don't edit your question to add "thank you" or follow up questions. Accept the most useful answer to say "thank you" and ask different questions for any follow up, referring to this question if it helps to give context. $\endgroup$ – Federico Oct 28 '16 at 10:24
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    $\begingroup$ Courchevel does not have a level touch down point. The touch down area has a slope of 12.5%, as compared to the steepest runway slope of 18.66%. See the airport diagram. $\endgroup$ – J Walters Nov 2 '16 at 19:18
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I never landed at Courchevel, but did some aerobatic training in Zar in the Giant Mountains of Silesia.

What I learned was:

  • A proper approach looks steeper than normal because the field inclination is steeper relative to the plane's attitude.
  • You need to flare sooner for two reasons:
    1. The sink speed relative to the rising ground is higher than normal, and
    2. The amount of pitch change needed to flare is larger.
  • Even with airplanes which have a strong ground effect (and where too fast a touchdown speed will normally result in a very long float) the flare was short, as was the rollout distance. Don't let speed bleed off too early, but stay on your approach speed until you are low enough to flare.
  • Airports with slope sit on the sides of mountains. In many cases, the approach is already over rising terrain. When landing with a headwind, the wind will create a downdraft along the approach so the sink speed during the approach will be higher than normal. For glider pilots this is the biggest danger - once you are too low, you will hit the ground short of the runway.
  • Most inclined runways show a variation in inclination along their length. This means that the relative sink speed and the necessary pitch change for a successful flare will vary with the touchdown point. Stay alert, no landing is routine!

The landing configuration and approach speed were not different from that on regular airports with level runways. Different was mostly the height at which the flare is begun. Also, at first I needed getting used to staying on my approach speed until I was low enough to flare - you need more energy to keep the airplane flying until it is level with the ground (i.e. climbing uphill!), so the final approach and flare must be executed precisely for a good landing.

When I saw the runway at Zar for the first time I thought the location is sheer madness. After a few landings I learned to appreciate the benefits: Very short roll-outs and planes would land uphill only, so they come to a stop where the (downhill) take-off run could begin. But the approaches need to be precise (we did mixed motor and glider flying) especially with gliders if you want to keep your fellow glider students happy.

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  • $\begingroup$ For Courchevel, see this instructional video. The angle between the glide path and the runway is 17% at the threshold. $\endgroup$ – mins Nov 1 '16 at 20:47
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As far as landing in a up-sloped runway is considered, the pilot will make a lower approach if not careful as he/she may consider the ground before to be sloping up as well. From flytime.ca:

When a runway is upsloping, the pilot thinks that the runway continues on an upslope from the terrain before it, hence thinking the terrain in front of the runway is upsloping as well. The pilot will judge their altitude as too high, because they perceive the terrain continues on an upsloping, positive angle towards the runway and will consequently plan a low approach that can cause landing short of the runway.

Sloping runway

Image from flytime.ca

Another thing to note is that the landing roll will be reduced (on the other hand takeoff roll would be increased, if takeoff is on uphill direction; else, it's reduced). For example, in this airport, the actual landing point is level- shortly after the aircraft touches down, it will start traveling uphill, and the landing roll will be shorter. One (passenger) describes the landing as:

During the approach we were below the runway and climbed up to it to land. After touchdown, we slowed down very fast due to the upslope. Very different than the normal runout after a landing.

Of course the location of this particular runway means that the landing has to be done correctly the first time around.

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Its not the upslope at Courchevel which makes landing there hard - its the big whopping cliff at the end of the runway. There is no go around so its a one-shot deal.

In general though, up sloping runways give two effects that I can think of

  1. The runway on approach would look different to a flat runway, this might have the effect of making an inexperienced pilot think they were too high.

  2. The landing roll would be shortened by being on an upslope.

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    $\begingroup$ Tenzing-Hillary airport at Lukla was also always said to have no possibility to go around, until this video clearly proved it's not true. The terrain around Courchevel looks quite similar, so going around is likely possible from similar point. $\endgroup$ – Jan Hudec Oct 27 '16 at 17:45
  • $\begingroup$ @JanHudec I think the pilot of that otter may have needed a change of clothing. I'm going to bet he didnt recommend that course of action routinely too. $\endgroup$ – Jamiec Oct 28 '16 at 8:15
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Courchevel is one of a few airports that has such a gradient but ill talk about it a bit more generally. Ron makes a good point in his comment that the plane actually touches down on a fairly level part of the runway then uses the up slope to slow down. With this in mind you must consider a few things, for one your touch down point must be at the more level end of the runway. If you think you are not going to make that, GO AROUND. Due to the mountains and up slope a go around is going to be a Vx scenario to make sure you get the best angle of climb.

In a more general sense you are going to want to be a little more nose up if landing uphill on a runway. I fly into KDDH which has a 0.8% gradient (barely noticeable) but when landing up hill I am a bit nose high to keep it safe. Its not a terrible idea to keep back pressure on and relive nose gear loads but this should be done anyway. Unfortunately the planes I fly are not permitted on grass strips and Im still working on really nailing my landings so 0.8 is the steepest I have flown into as of yet.

This site has some interesting info as does this site

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  • $\begingroup$ Is there any runway that has more gadient? that you have to be "flying up" to land on? I originally thought it would be that way in the mentioned runway, and was curious what knowledge is required to land on such runways $\endgroup$ – Ronan Dejhero Oct 26 '16 at 14:18
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    $\begingroup$ @RonanDejhero Courchevel has the record as the steepest at 18.6%, another harrowing one is Tenzing-Hillary in Nepal with a 11.7% grade but is considered the most dangerous airport in the world. $\endgroup$ – Ron Beyer Oct 26 '16 at 14:28
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    $\begingroup$ "Ron makes a good point in his comment that the plane actually touches down on a fairly level part of the runway". This seems to be a recurrent story. The aerodrome plate indicates 12% upslope for the first part of the runway, and this is clearly visible on this snapshot from this video of a qualification training specific for this altiport. $\endgroup$ – mins Nov 1 '16 at 20:21
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I landed many times at Courchevel. You can't just fly in. You need a training culminating in a permission to land there valid for 6 months. That should make it safe enough.

Sudden downdrafts can CFIT you just under the landing area. Sudden updrafts can make you land way too far. That's why the pilot is VERY reactive on final. Once on the ground you have to make sure you keep your speed up enough to make it to the top or you could get stuck midfield.

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As you could see in the video that Ron Beyer linked (2. comment on the question) trying to land slows you down substantially as you are effectively gaining altitude when landing on an incline as you need to level yourselfes to the ground. This will make it harder for the pilot as he will have to adapt to this behauviour and land with just the right speed to not loose gliding or aproach from too low and not take to long to stop on a this short runway.

In conclusion it will take some practise to learn what speed is the best for this particular landing, but that isn't really different for other runways. Another problem is the common ice due to the mostly cold wheather at 2000m above sea level, but that is not different to other airports in cold countries aswell.

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  • $\begingroup$ What do you mean, stall your engine? Aircraft engines are not susceptible to stall from the moderate increase in pitch required to land upslope. The only thing I can think of would be if the aircraft went to such a dramatic attitude for sufficiently long enough to unport the fuel lines. $\endgroup$ – J Walters Oct 27 '16 at 17:12

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