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REVERSE
LAUNCH PRIMER
Written February 2005
Written
by Joe Bosworth
Introduction
With
Australia’s strong thermic conditions and high percentage
of coastal flying sites, probably some 90% of all paraglider
takeoffs start with a reverse launch. Other parts of the world
also widely utilise reverse launches. Perhaps 25% of pilots
find reverse launches relatively easy to learn, another 25%
really struggle to learn to reverse launch and the middle ground
50% have varying degrees of difficulty in learning the reverse
launch techniques.
This
primer is intended to dissect the steps leading to successful
reverse launches so that the newbie and others who are not satisfied
with their reverse launches can become adept in a shorter time
and with a reduced struggle.
I
write this with the assumption that the reader already knows
something about ground handling from initial lessons, you just
aren’t as good as you want to be.
Your
author started as one who found great difficulty in learning
to reverse launch. I have had the benefit of having experienced
several sports, had outstanding coaches in all of them and have
also coached several sports. A common thread in the coaching
experiences has been in breaking down elements of execution
into many understandable small steps which when placed together
brings a good result.
With
the help of many experienced pilots I have analysed reverse
launching and have gained a reasonable proficiency. This primer
attempts to pass on the steps leading to good reverse launching
techniques.
Safety
By
definition, if you are reading this to learn reverse launching,
at some points in your learning experiences you will loose control
of your glider and will end up being dragged. Don’t feel
badly, I see even the very experienced still find themselves
being dragged once in a while.
That
being the case please take heed and:
1.
Wear your helmet anytime you harness up. I find that a good
way to remember this, as well as to never lose it, is to clip
your helmet to one of your harness loops every time you unclip
from your harness. If you do this then you will naturally
put on your helmet as the first step in buckling up. It will
also avoid the problem that some have had, that it losing
one’s helmet due to leaving it behind while packing
up.
2.
Wear stout clothing over arms and legs. Unless you are very
lucky you are going to lose some skin in any substantial drag
on almost any surface. Motorcyclists call it road rash. Save
yourself the recovery from road rash, wear at least the equivalent
of jeans to cover your legs and at least a heavy cotton jacket
on the upper body. A long sleeve shirt under the jacket is
also a good idea in all but very hot weather.
3.
Wear gloves with at least leather palms. Grabbing hold of
bare lines and pulling the glider in is tough on the hands
without leather gloves. It is up to you what kind of gloves
you might wear. My choice in hot weather is yachting gloves.
As crew members spend there time hauling on sail control lines
they have things pretty well in hand with good soft leather
that works even better when they get sweaty and damp and have
open tips on all or first digits which helps one grab particular
lines as one will want to do from time to time. Bicycle gloves
are somewhat similar but do not cover as much length of finger.
For cold weather use there is not much that the motorcycle
guys haven’t sussed out for comfort and warmth.
Footwear
Footwear
doesn’t quite fully come under the guise of safety but
it is well worth comment. When it comes to landing on rough
terrain good ankle support will save ankle some ankle sprains.
However
don’t undervalue the role of good foot support and traction
to aid reverse launches. I went a long time wearing light boots
without either good support or good traction aiding soles. That
was during a period in which I was a lousy ground handler.
When
I got good boots my handling improved. You don’t have
to spend a lot of money, you are not going hiking or mountain
climbing, as least as a primary purpose.
Hooking Up and the Reverse Turn
As
by the definition from the Introduction, you already know enough
about ground handling from your initial lessons to know how
to hook up and get into the reverse position. You also know
how to layout the glider and its lines.
However
I can’t help but make a few observations.
1.
I like to be certain that the glider’s lines are in
order and not twisted before getting into my harness but it
can be reasonably argued that this can be done after step
3 below. I do it first as any pulling on lines means the glider
can get away without me attached.
2.
Always hook into your harness using the same sequence. I don’t
really believe that it makes much difference what the sequence
is, just make it always the same. Falling into a single pattern
will help one assure that they are properly hooked in. I also
shun any help from others as that is sure to break the pattern
and adds to the possibility that something has been omitted.
3.
Once in your harness do a visual check to assure that you
haven’t forgotten anything and this includes twisted
straps and buckles that have not been pushed home to the secure
position.
3.
When in strong winds or in gusts it is a good idea to pick
up brake lines with the correct hands before locking into
the karabiners. In lighter, non-gusting conditions I sometimes
don’t pick the brakes until the karabiners are attached
but before turning into the reverse position. Your choice
is a matter of balancing safety and convenience.
4.
At some point in time you will want to be able to turn in
either direction while launching. This is so because hill
sites sometimes have winds at that vary at some considerable
wind direction between canopy height and body height. When
the vector moves the glider to your (reverse) right when you
need to turn left you have some problems and visa versa. The
problems are solvable but can become simple by initiating
a reverse turn from the other direction.
However,
don’t try to learn turning both directions until you have
a single direction seared into your brain and it becomes a reflex
action. How long does this take? I don’t know about your
learning habits but I am 1½ years into the learning process
and don’t even think about going both ways. One thing
I do know is that I will keep my regular direction as the one
to do by reflex action and the other to be initiated only by
very conscious prior decision.
Hand Positions
Cross
or not -
Since turning into a reverse position results in crossed risers
you need to decide whether you are happy to cross your hands
so that the final forward position right riser is in your right
hand or whether you are happy to let going of lines and risers
and brakes during the forward turn in order to get your hands
properly placed for a forward launch.
I
recommend learning to reverse launch with crossed hands. The
best reason for my recommendation is that you have your hands
on some controls at all times during the launch and turn sequence.
I found that any learning experience became a reflex almost
immediately on starting and I have felt comfortable ever since.
However
if you have trouble coming to grips with cross-control use,
by all means use the straight-arm approach. It works as well
99% of the time.
The
one rule that needs to be followed for either method is to be
sure that both A risers are clear on top and both D risers are
clear on the bottom. I am surprised at the number of people
that don’t check and have to abort launches to get things
in order. You can not get a good inflation unless the A’s
are cleanly on top and you can’t get the glider cleanly
down without the D’s cleanly on the bottom. Ask for help
if it is not absolutely clear how to accomplish this
Which
risers –
There are a wide variety of ways to arrange the risers and brakes
in your hands whether crossed or not. There are advocates and
good reasoning for all of the alternatives. My view is that
no single choice is best and you need to practice two or three
methods depending on kiting / launch conditions. Let’s
talk our way through this.
Before
we start however let’s get the brakes correct. I like
to use the cross arm approach and to grab the brakes in the
correct hands while still facing forward as we learned for forward
or so-called Alpine launches. Getting your hands on the brakes
at this point assures two things; firstly the matter of safety,
if the wing catches a gust while turning into the reverse position
we have a chance to quickly kill the glider and secondly, it
assures that the brakes will be clear for control once we have
turned into launch position after inflating the glider.
We
know by now that lifting the A risers inflates the wing and
initiates the lifting process. We also know that pulling on
the brakes causes the trailing edge to drop, eventually stall
and the wing to settle back down.
However
a couple of problems with using brakes arise. One is that overuse
of the brakes when close to full inflation will increase the
lift of the wing, sometimes enough to cause a premature takeoff.
The second is that brakes are relatively slow acting, at least
compared to using C’s or D’s.
D’s
do a better job of killing the wing quickly than do the brakes,
so when in doubt or when getting into impending trouble use
D’s rather than brakes. This becomes more critical in
stronger winds and less important the more benign the conditions.
Interestingly
the C’s are the best way to control the wing in really
marginally strong conditions; the kind which you may choose
to not subject yourself to with sound thinking. The good thing
about C’s are that they cause a crease to form across
the wing from tip to tip when which reduces wing area and therefore
the pull of the wing. More about this later.
I
will discuss my personal preferences and why I got to this point.
But before I do, let me state the obvious and that is that all
wings and people are different. You need to find what works
best for you and your glider for differing conditions that will
be found through practice.
My
glider to now has been an overly large DHV1. It rises slowly
and seems quite heavy.
In
most conditions except for those which are starting to get too
strong, I get the best inflation by holding one A riser in each
of my crossed hands. This allows me to initiate the strongest
inflation to counteract the weight and slow rise. This also
allows me to differentiate the lifting action if one side starts
to come up slower than the other. Simply slowing the lift on
one side, speeding the lift on the other or a combination of
the two works wonders in getting an even inflation. So does
dropping the A on the faster rising side and applying a little
brake. I like the variety that this gives me in most conditions
which leads to my favouritism.
However;
let’s not throw out the A and D option. Both A’s
in the hand in the direction you are going to turn and both
D’s in the other hand is the favourite of many. The biggest
advantage that this allows the fast killing of the glider when
needed because of the previously mentioned fact that D’s
react on the wing more strongly than do the brakes.
If
the wing starts to rise un-evenly you still have some control
by moving your hands laterally.
Let’s
say that when looking at the wing from the reverse position
that the left side starts to riser faster than the right side.
You need to slow the left side and speed the right side. This
will occur if you move your hand with the A’s to the left
which brings the right A into more prominent play. At the same
time move the hand with your D’s to the right which provides
the equivalent of a bit more braking action to the wing’s
left side. When things even out move both hands back together
in the middle of your body. The more responsive your glider
the better this works. As previously mentioned, I get less control
out of this method than I like so I don’t use this much
though I still practice it, especially when I intend to stay
in reverse kiting position for a while.
For
both of the above methods it is important for a straight inflation
to start with both hands together and to keep them together
until conditions dictate to the contrary.
In
conditions that border on too strong I recommend using A’s
and C’s. The C’s are used as per the D’s mentioned
above with the advantage that pulling forces are reduced. As
much as anything is certain in paragliding, holding C’s
with some pressure while the glider is on the ground will keep
the glider down. At least down better than brakes or D’s.
If
it is that strong and you still make your decision to try an
inflation you can reduce the pulling loads by keeping the C
hand close to your belt buckle and only start to feed it out
to the hand with A’s after that hand has started to lift
the glider.
Handling on the Ground
It
is important that the glider remain on the ground when you want
it on the ground. This is necessary between the time that you
hook in to the karabiners to the time you commence inflation.
The time may be from moments to several minutes, depending on
your waiting for traffic clearances and/or favourable wind cycles.
The
safest condition occurs with the leading edge of the glider
partially inflated and sufficient pressure on the A’s
that the edge is about 15 inches – 35 centimetres above
ground. In this situation you want just enough light pressure
on your C’s, D’s or brakes, (see previous section),
to assure that air doesn’t get under the glider and/or
you can apply further pressure to control the bottom trailing
edge.
While
you are waiting with your glider partially lifted on the ground
you are in a perfect position to determine if you are set up
squarely and perpendicular to the wind. In almost all conditions,
(that will be discussed next), if you are square to the wind
you will get a level and even inflation. If you are not square,
the downwind tip will inflate first and the upwind tip slower
while tending towards collapse in exceptional circumstances.
Pick
up a wisp of grass or dust and let it go to judge wind direction.
Even better, induce a partial inflation, raising the leading
edge so that the trailing edge barely leaves the ground then
drop it back down with C’s, D’s or brakes. If it
pulled up evenly you are likely square to the wind. If it did
not come up evenly you are not square to the wind. Take a couple
of steps towards the side that was slower inflating and try
again.
The
one major exception to the rule of being square to the wind
is when the wind at the elevation of an inflated canopy is at
some vector to wind direction at body level. We have one site
in particular where the wind at canopy level often is at a vector
of up to 30 or so degrees to body level wind direction. The
best way to determine this is to allow others to be wind dummies
and watch what happens to their canopies during inflation.
The
experienced ground handler can inflate evenly even with a vectoring
wind by differentially applying risers. You/we are not there
yet. The best recourse is to shift most of the way into the
vectoring wind and iniating inflation with the upwind A a little
in lead of the downwind A.
Inflation
It
is time for inflation but before we do so I wish to raise two
points that I had to figure out for myself and I haven’t
seen written elsewhere.
The
first has to do with hand position on the brakes after inflation
and while the glider is overhead. I see many low hour pilots
hold on to the brake handles with the strength of a gorilla
swinging in the trees. And then they complain that they can’t
feel what the glider is doing. Among other things, your hands
and arms need to be relaxed to get any real feel.
I
have found that to insure relaxation and to improve feel that
I rest only the first knuckle of two or three fingers across
the bottom of each brake handle. This applies to feeling the
glider in the air and on the ground as well. It is all but impossible
to be tense through two fingers and it is amazing how much feel
you achieve. This also allows you to provide control inputs
at varying levels of force whether through finger movement,
hand movement or arm movement. Waking up to this was a major
break through for me to raising the level of my ground handling
and inflation.
The
second break through was to realise the importance of loading
the glider wing during inflation. There are two aspects of this,
static weight and applied weight.
We
know that gliders are designed to be flown at a certain load,
mostly near 3 ½ kilograms per square meter of wing area.
We also know that the greatest stability occurs when the glider
is in the air and flown near the top side of its design weight
range. It takes a very strong off setting wind to disturb the
shape and direction of a well-loaded glider. Of course this
is also made easier since we auto-center our weight under the
wing due to gravity while flying.
I
started flying with a glider on which I was in the bottom half
of its design weight range. I suffered with premature lift off
and difficulty in getting the glider fully stable with canopy
overhead while still on the ground. Then I thought it through
and started to add ballast. Achieving stability became easier
and easier with more ballast. I now like to take off ballasted
to about 70 to 75 percent of the design weight range. So much
for static wing loading, let’s go on to applying the load.
I
see many people commencing inflation with the entire load going
through the A risers. The wing was designed to have best lift
and stability when all risers are loaded through the karabiners
and then into all risers and lines as dictated by line lengths.
I have found that emulating the flying load pattern early in
inflation provided greater stability. Use you’re A’s
by lifting in a vertical direction and then in an arc until
the canopy is suitably overhead and flying, even if you are
still on the ground. (Don’t start by pulling on you’re
A’s). At the same time that you start raising the A’s
load the karabiners through your hip action. Pull back with
your hips and then start to bend your knees as the wing rises.
I like to insure this by putting my buttocks against my harness
seat front and feeling the initial load.
Try
to take most of the load through your hips. This evenly loads
the glider through all risers. This also brings the major forces
that you wish to control and resist closer to the ground where
it is working against a shorter fulcrum length. This also allows
you to best resist through your legs where you have the greatest
strength and to also bring the rest of your upper body weight
into action through a longer fulcrum length. Remember your days
on a “see saw or known as a teeter totter in NA”?
The low weight person on the long arm easily balanced the heavier
person on the shorter arm.
While
you are still on the ground, try to apply load into the wing
by leaning. In the first instance backwards while in the reverse
position and later forwards when in the forward position. This
transfers more of your body weight from the your contact point
with ground which is made up by increasing load lifted by the
wing.
Of
course, as/when the wing goes off center that lean should go
towards the low tip of the glider to augment the braking adjustment
that you also make. If leaning sideways is not enough, start
shuffling your feet. Here is where those bent knees from earlier
come into prominent play. All athletic endeavours involving
lateral movement are best taken with a lowered body silhouette.
Some
people have problems with the wing over-shooting on lift off.
Applying early body weight helps avoid this. But it is also
usually necessary to slow the wing’s forward momentum
as it nears the top of its inflation. Of course you have learned
to do this by applying brakes, D’s or C’s as previously
discussed. But also don’t forget that a lot of this forward
momentum can be slowed by moving under the wing earlier in the
inflation process.
Once
the wing is overhead I like to immediately forward turn and
initiate a smooth forward movement to gain airspeed into lift
off. I turn immediately because there are more bad things that
can happen in the transition than good things and the shorter
the time the least time for the unexpected.
One
of the bad things is premature lift off. This can occur due
to a wind gust or too vigorous a brake application. Either way
the least harm will usually occur if you accept your plight
and fly off. Simply give the glider the best opportunity to
fly by raising your hands. Usually the weight of you and harness
will cause the risers to unwind and off you go to a good flight.
Only very occasionally will you need to consider reaching up
at arms length to apply outwards pressure to unwind the risers.
Let nature take its course first but above all don’t panic.
Practice
If
you wait to apply all of this to the takeoff situation you will
never learn fast enough. There is no viable alternative to practising
this stuff on a level field while ground handling. You can get
a year’s worth of takeoff practice into a weeks worth
of level field ground handling. How many inflations to become
proficient?? I don’t know your learning ability but don’t
be despondent if it takes a few hundred inflations in different
conditions. But of course what level of proficiency are you
happy with?
Have
fun.
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