How to landout on a steep uphill final?

A runway that I frequent has no straight ahead option for a rope break at 100 feet AGL. There is a however a highly recommended hayfield with a 90 degree turn from the takeoff heading onto the landout final. The field is 100 feet lower in elevation than the departure runway, so it is reachable if you do all the right things. For example, you need to get over the tops of the trees on the near side of the field.

So let's say the landing area is steep, say it rises 20 feet for a 200 run. Depending on when the hay was last cut, the vegetation height ranges from stubble to 30" of consistent grasses. The ground is likely to be very bumpy. Boulders have been removed from this field to facilitate haying machinery. There may be some dips, but no ditches and no hidden branches or stumps. There are power lines running down the right side of the field and there is a two lane paved road on the other side of a ditch at the end of the run out. There is sufficient run out, but not much to spare. The field gets more and more level as you get closer to the road. On the far side of the road is a cornfield, so flying high over the road is not a good option.

So I want to touch down with minimum energy. My first thought is to flair to level flight much higher than normal, say 10 feet above the ground after the flair, pull the stick back gradually to bleed off speed until the ground comes to meet my level flight. Careful not to stall prematurely of course.

OR do I flair at a normal height and ride the ground effect uphill? I imagine that I might fly into the slope and touch down with more energy than I would like and possibly do a ground loop or otherwise damage the glider (and/or my body). The field may tilt a bit left to right.

The fact that the field is tilting up steeply in front of me is going to distort my perception and that is the other reason that I'm inclined to flair deliberately high. That gives me more time to see what is happening and adjust.

Opinions and suggestions? I'm thinking about a particular field, but I'd kinda like to know in general how to approach this type of field because level fields are rare in my area.

I will of course discuss this with knowledgable people at my club, but I'd like to think about it and get some ideas before I bring it up at the airport.

I've not had occasion to land steeply uphill but I've thought about that scenario many times. I would plan to carry enough extra energy so that I could round out before arriving at the hill and thereby follow the uphill slope close to the terrain until the energy has bled off and then settle in for a slow touchdown. It may be trickier than I visualize though.

On 6/9/2013 7:33 PM, son_of_flubber wrote:

Paraphrasing wildly...

"Opinions for landing technique into an uphill field, please..."

Snip

So I want to touch down with minimum energy. My first thought is to flare
to level flight much higher than normal, say 10 feet above the ground after
the flare, pull the stick back gradually to bleed off speed until the
ground comes to meet my level flight. Careful not to stall prematurely of
course.

Or do I flare at a normal height and ride the ground effect uphill?

Them's two of the basic options, alright (though "first thought" strikes me as
decidedly bizarre when viewed from the perspective of attempting to do the
same when landing on a LEVEL field/runway)...

I (also: RFW) imagine that I might fly into the slope and touch down with more energy
than I would like and possibly do a ground loop or otherwise damage the
glider (and/or my body). The field may tilt a bit left to right.

With this option you're (IMO) zeroing in on "planning goodness"...i.e. "flying
it on w/o really attempting to flare." As for worrying about the excess
energy, you'll be astounded how rapidly a noticeable uphill WILL dissipate
excess energy in any event, short field or not. That's the voice of experience
from landing gliders on uphill western runways.

The fact that the field is tilting up steeply in front of me is going to
distort my perception...

Very definitely! Perception likely would result in your (inadvertently) being
forced to implement Option 1) or 2) if you hadn't priorly thought things
through as you're evidently doing. Why? If you accurately follow the "how to
judge flare height" procedures you've (probably) been taught (i.e. focusing
eyeballs "well out in front of the glider" to judge flare height), odds are -
going into an uphill-sloping field - you'll flare anywhere from higher than
you expect to WAY higher than you expect, since the ground beneath you is
farther away vertically than the ground at which you're gazing to judge your
roundout height. Having flared high, likely also to very quickly-in-time
follow, is "the dreaded drop in." (Whump! Bad for plane and potentially bad
for your back.) The first broken sailplane I ever saw had this happen to it. A
Phoebus, dropped in from (per the pilot) 6 feet after he "routinely flared"
into an uphill field judging height from the FAR end of the field. Broke the
plywood bulkhead to which the gear was mounted, better I suppose than breaking
the fuselage, but still expensive to fix.

...and that is the other reason that I'm inclined to
flare deliberately high. That gives me more time to see what is happening
and adjust.

I suppose that's reasonable in theory, but (IMO) practice is likely to
significantly (and negatively) differ, primarily because: 1) (commenting
generally) "higher above ground than normal" in the flared condition isn't a
good situation from which to begin an energy experiment, and 2) (commenting
specifically) more or less by definition "the flared condition" is a low
energy condition. Bottom line is you will NOT have any excess energy available
to "adjust" or otherwise "fly 'er onto the ground" once flared.

Opinions and suggestions? I'm thinking about a particular field, but I'd
kinda like to know in general how to approach this type of field because
level fields are rare in my area.

Personally, my long-standing (happily never required) mental plan for landing
in a short uphill field is to judge my roundout by bringing my focal point
MUCH closer to the touchdown target point, and attempting a flown-on touchdown
from "normal height," then depend on the hill to help dissipate the
higher-than-theoretically-ideal actual touchdown speed. If I misjudge the
actual touchdown point in the sense the field meets me "too early/before I
expect it to" then any "flying bounce's" 2nd arrival from the excess energy
will be in part mitigated by the upward sloping field in any event. Further,
in my experience "flying touchdowns" are generally gentler than "flying
energy's gone" (and you misjudged the agl height, bozo) arrivals.

It should be interesting to learn others' opinions and experiences...

Bob W.

On Sunday, June 9, 2013 9:12:04 PM UTC-6, Steve Koerner wrote:
I've not had occasion to land steeply uphill but I've thought about that scenario many times. I would plan to carry enough extra energy so that I could round out before arriving at the hill and thereby follow the uphill slope close to the terrain until the energy has bled off and then settle in for a slow touchdown. It may be trickier than I visualize though.

I love uphill landings. They work exactly as you describe above. Aim at the bottom of the hill with a bit of extra speed. When you rotate to match the hill slope the glider stops in a hurry. Just keep your nerve on short approach when the canopy is full of hill. It adds a new dimension to short-field landings.

Steve's got it spot on.

My very first landout was into an up hill freshly plowed field. I flew it
on with extra speed and the roundout included a gentle climb to touchdown.
Roll out was very short!


"Steve Koerner" wrote in message
...
I've not had occasion to land steeply uphill but I've thought about that
scenario many times. I would plan to carry enough extra energy so that I
could round out before arriving at the hill and thereby follow the uphill
slope close to the terrain until the energy has bled off and then settle in
for a slow touchdown. It may be trickier than I visualize though.

Very much worth reading this booklet. Kai spent a lot of time on key topics, this one included. See page 6.

http://www.cumulus-soaring.com/books...rport_Ldgs.pdf



On Sunday, June 9, 2013 9:33:46 PM UTC-4, son_of_flubber wrote:
A runway that I frequent has no straight ahead option for a rope break at 100 feet AGL. There is a however a highly recommended hayfield with a 90 degree turn from the takeoff heading onto the landout final. The field is 100 feet lower in elevation than the departure runway, so it is reachable if you do all the right things. For example, you need to get over the tops of the trees on the near side of the field.



So let's say the landing area is steep, say it rises 20 feet for a 200 run. Depending on when the hay was last cut, the vegetation height ranges from stubble to 30" of consistent grasses. The ground is likely to be very bumpy. Boulders have been removed from this field to facilitate haying machinery. There may be some dips, but no ditches and no hidden branches or stumps. There are power lines running down the right side of the field and there is a two lane paved road on the other side of a ditch at the end of the run out. There is sufficient run out, but not much to spare. The field gets more and more level as you get closer to the road. On the far side of the road is a cornfield, so flying high over the road is not a good option..



So I want to touch down with minimum energy. My first thought is to flair to level flight much higher than normal, say 10 feet above the ground after the flair, pull the stick back gradually to bleed off speed until the ground comes to meet my level flight. Careful not to stall prematurely of course.



OR do I flair at a normal height and ride the ground effect uphill? I imagine that I might fly into the slope and touch down with more energy than I would like and possibly do a ground loop or otherwise damage the glider (and/or my body). The field may tilt a bit left to right.



The fact that the field is tilting up steeply in front of me is going to distort my perception and that is the other reason that I'm inclined to flair deliberately high. That gives me more time to see what is happening and adjust.



Opinions and suggestions? I'm thinking about a particular field, but I'd kinda like to know in general how to approach this type of field because level fields are rare in my area.



I will of course discuss this with knowledgable people at my club, but I'd like to think about it and get some ideas before I bring it up at the airport.

In article ,
"Dan Marotta" wrote:

Steve's got it spot on.

My very first landout was into an up hill freshly plowed field. I flew it
on with extra speed and the roundout included a gentle climb to touchdown.
Roll out was very short!



Did exactly that at the Chilhowee Sports Nats a few years ago. Got low
and backtracked to my chosen field only to find another glider sitting
in the middle of it. Went to plan B, a plowed-and-planted field that
covered the top of a prominent hill. I needed to stop before going over
the top of the hill or else it would quickly become an attempt at a
downhill landing. I approached well below the level of the crest of the
hill carrying extra speed to "zoom" up the hill. Matching the upslope
was surprisingly easy. Ran out of airspeed darned quick and neatly
settled on at very low speed (no spoilers). Stopped in the soft dirt way
before running over the crest of the hill.

On Sun, 09 Jun 2013 20:12:04 -0700, Steve Koerner wrote:

I've not had occasion to land steeply uphill but I've thought about that
scenario many times. I would plan to carry enough extra energy so that
I could round out before arriving at the hill and thereby follow the
uphill slope close to the terrain until the energy has bled off and then
settle in for a slow touchdown. It may be trickier than I visualize
though.

I've landed out on a fairly steep upslope a couple of times in my
Libelle. Both times I rounded out at a normal height at the bottom of the
slope and flew up at a more or less constant height AGL until the glider
settled onto the ground. Like you I thought it would be difficult, but it
wasn't. In both cases the slope had fairly long, sparse dry grass on it,
long enough to be part-way up the fuselage side after I stopped rolling.
As in this case you tend to judge hold-off height against the top of the
grass, that probably gives a bit more leeway without putting you high
enough to arrive hard. The space you need for this type of uphill landing
is gratifyingly short: flying uphill bleeds off energy quite fast even if
you are in ground effect.

PS: I had a bit of practise a few years earlier in a K13 during a visit
to Nympsfield. If there's a northerly blowing, the south end of the field
is quite uneven enough to require contour chasing after you round out.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

On Sunday, June 9, 2013 9:33:46 PM UTC-4, son_of_flubber wrote:
A runway that I frequent has no straight ahead option for a rope break at 100 feet AGL. There is a however a highly recommended hayfield with a 90 degree turn from the takeoff heading onto the landout final. The field is 100 feet lower in elevation than the departure runway, so it is reachable if you do all the right things. For example, you need to get over the tops of the trees on the near side of the field.



So let's say the landing area is steep, say it rises 20 feet for a 200 run. Depending on when the hay was last cut, the vegetation height ranges from stubble to 30" of consistent grasses. The ground is likely to be very bumpy. Boulders have been removed from this field to facilitate haying machinery. There may be some dips, but no ditches and no hidden branches or stumps. There are power lines running down the right side of the field and there is a two lane paved road on the other side of a ditch at the end of the run out. There is sufficient run out, but not much to spare. The field gets more and more level as you get closer to the road. On the far side of the road is a cornfield, so flying high over the road is not a good option..



So I want to touch down with minimum energy. My first thought is to flair to level flight much higher than normal, say 10 feet above the ground after the flair, pull the stick back gradually to bleed off speed until the ground comes to meet my level flight. Careful not to stall prematurely of course.



OR do I flair at a normal height and ride the ground effect uphill? I imagine that I might fly into the slope and touch down with more energy than I would like and possibly do a ground loop or otherwise damage the glider (and/or my body). The field may tilt a bit left to right.



The fact that the field is tilting up steeply in front of me is going to distort my perception and that is the other reason that I'm inclined to flair deliberately high. That gives me more time to see what is happening and adjust.



Opinions and suggestions? I'm thinking about a particular field, but I'd kinda like to know in general how to approach this type of field because level fields are rare in my area.



I will of course discuss this with knowledgable people at my club, but I'd like to think about it and get some ideas before I bring it up at the airport.

I had a very rough landing in France in a security field that was actually an altiport. An altiport is on a steep uphill field or runway. Mine was a rough field, but the only know field to safely land withing 20 kilometers. Such is the flying in the French Alps.

Luckily, all I did was twist the landing gear and blow the tire, and scrape the gel coat off the bottom of my glider (as well as demoralize my ego) from my hard impact. I came to an abrupt stop 100 yards short of where I thought I would first touch down and roll onward. I had landing flaps configuration, which was an error for upslope landing. When I pulled hard to flair uphill, I had only drag and no lift from the wings. You need some good L over D to flair uphill. To say the least, I had every difficulty getting the glider back into the trailer without functioning wheel gear and not getting the landing gear door closed.

If I had to do it again, I would go into the flair with at least 65 knots with only minimal positive flap setting and aim farther down the field than my gut instinct would tell me. (Psychologically, your senses will tell you otherwise.) Because of the illusion that you are driving into the ground with too much speed, actually you do not have enough airspeed, and you are actually flying straight into the slope of the hill, you will touch before you ever intended without enough airspeed to pull up abruptly. You will actually have to flair "much higher" than your perceptions advises you to.

If you fly in rolling hill territory or in tall mountain territory, you must make study of this type of landing because you will eventually have to do it. Even Klaus Ohlmann, the world's best mountain gliding expert, has destroyed an Nimbus 2DM (and other gliders) landing at an altiport uphill. Take note of how difficult this can be for experts with tens of thousands of mountain gliding experience.

Happy mountain soaring, it is extremely rewarding with the challenge and the joy of the views. Nothing better in this life experience.

On Monday, June 10, 2013 11:48:25 AM UTC-4, Papa3 wrote:
Very much worth reading this booklet. Kai spent a lot of time on key topics, this one included. See page 6.

http://www.cumulus-soaring.com/books...rport_Ldgs.pdf

This is exactly what I need to study. Thanks!