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Old June 11th 13, 06:38 PM posted to rec.aviation.soaring
Glen Douglas
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Posts: 6
Default How to landout on a steep uphill final?

Having done this in a Capstan, landed OK, but as it had no wheelbrake it
rolled backwards at 25 kph, down the hill and into the gatepost. It took 11
months to rebuild the damage to the wings, elevator, tailplane and rear
fuselage.

IF your brake is suspect or you don't have one, groundloop the glider
sideways before you stop

Glen Douglas

At 05:02 11 June 2013, Frank Whiteley wrote:
On Monday, June 10, 2013 2:37:20 PM UTC-6, wrote:
On Sunday, June 9, 2013 9:33:46 PM UTC-4, son_of_flubber wrote:
=20
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
9=
0 degree turn from the takeoff heading onto the landout final. The field
i=
s 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
top=
s of the trees on the near side of the field.
=20
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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
ma=
chinery. 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
fiel=
d 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
opti=
on.
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So I want to touch down with minimum energy. My first thought is to

fl=
air to level flight much higher than normal, say 10 feet above the ground
a=
fter 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.
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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
tha=
n 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.
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The fact that the field is tilting up steeply in front of me is going

t=
o distort my perception and that is the other reason that I'm inclined to
f=
lair deliberately high. That gives me more time to see what is happening
a=
nd adjust.
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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.
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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
a=
irport.
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I had a very rough landing in France in a security field that was

actuall=
y 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
kilometer=
s. Such is the flying in the French Alps.
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Luckily, all I did was twist the landing gear and blow the tire, and

scra=
pe 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
t=
hought I would first touch down and roll onward. I had landing flaps
confi=
guration, which was an error for upslope landing. When I pulled hard to
fl=
air 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
gettin=
g the glider back into the trailer without functioning wheel gear and not
g=
etting the landing gear door closed.
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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
tha=
n my gut instinct would tell me. (Psychologically, your senses will tell
y=
ou otherwise.) Because of the illusion that you are driving into the
groun=
d with too much speed, actually you do not have enough airspeed, and you
ar=
e actually flying straight into the slope of the hill, you will touch
befor=
e you ever intended without enough airspeed to pull up abruptly. You will
a=
ctually have to flair "much higher" than your perceptions advises you to.
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If you fly in rolling hill territory or in tall mountain territory, you

m=
ust 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
de=
stroyed an Nimbus 2DM (and other gliders) landing at an altiport uphill.
Ta=
ke note of how difficult this can be for experts with tens of thousands

of
=
mountain gliding experience.=20
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Happy mountain soaring, it is extremely rewarding with the challenge

and
=
the joy of the views. Nothing better in this life experience.

Lleweni Parc (AKA Looney Park). Final at 75kts minimum over the river to
r=
ound out and land uphill and stop at the launch point. Much steeper than
t=
he 10/1 described by the OP.

Frank Whiteley