El Inca Llora (a song about Peru)
The Nose High Launch
Copyright © 2005 Don Burns
There is little more sacred to the hang-glider pilot than launch technique.
While there are many varied techniques and preferences for various aspects
of launching, nearly all pilots can chant in unison the commonly accepted
mantra, "hold the nose low and run hard!". "Nose low, run hard" launches,
have been the accpted technique since the days of the standard rogallo and
continue to be the most undisputed advice for good launches. Well, this
article is about to preach heresy.
Why? Because we want to stir up contraversy for the fun of it? No, but
because this accepted method of launching overlooks some of the most
important ingredients for successful launches and safe flying, and exists
because of some mythical premises. Even if the hair on the back of your
neck is standing up in reaction to the claim that it is ok to hold your
nose high on launch, or it is less acceptable to run with your nose low,
read on for some good analytical discussion.
Before we can effectively define what does and doesn't make a successful
launch, perhaps we should define what a successful launch is. The popular
method for judging a launch, in fact, is often to measure it against the
two elements "Nose Low", "Run Hard". Seldom are hang-glider pilots heard
commenting on a) the level of pitch and roll control during a launch,
or b) the transition from running to flying, or c) the change
in angle of attack during launch.
Yet, if we were to point these qualities out, few would argue with a)
the pilot should be in full control during the take-off run and b) the
glider should be loaded gradually and smoothly during the take-off run and
c) the angle of attack should change very little during the take-off
run. But are these qualities really considered when judging a launch?
As a hang-gliding instructor of over 25 years, allow me to share a method of
observation of foot launches that you may not have considered before. One of
the key skills a hang glider instructor must possess is the ability to observe
and analyze student flights. Hang gliders conform to the laws of physics 100%
of the time, and behave according to some very simple principles. Often subtle
changes in angle of attack or bank angle are difficult to see when focused on
the student's hand or body position, and the visual scope only includes the
control bar. Watching the entire glider causes these subtle changes to be
more easily discernible.
Next time you find yourself observing launches, position yourself so that you
can watch from behind the launching pilot, and focus on the top center of the
glider, at the kingpost, or where the kingpost would be on a topless glider.
Note the change in angle of attack during launch, as well as subtle changes
in direction and bank that may occur during launch. Without looking at how
crouched over or powerful the pilots strides are on launch, ask yourself,
how in-control is this pilot really?
What is "Nose High"?
When observing launches, note what seems to be the accepted angle of attack
for a "good" launch. Typically, this is quite nose-low. Speaking in terms
that we can quantify, the accepted angle of attack for any given launch is
often close to level with respect to the horizon. If you haven't noticed
this, notice it now. In fact, the next time you pick your glider up to
launch, notice the angle of attack with respect to the horizon when you feel
most comfortable to start your take-off run.
Compare this to what the angle of attack the glider has while in flight. In
most cases it will be significantly lower. In fact, if you maintained the
angle of attack, with respect to the horizon in flight, you'd find youself
flying at very high speeds. Even on beginner gliders, this speed is
significantly above what most humans can run at.
So, if you hold the angle of attack at something the glider will seek when
it is flying 40 mph, do you intend to launch at that speed? Of course not!
SO, what has to happen then for you to be able to launch at running speeds?
Right, the nose has to come up during the launch run. In fact, this is what
you will observe for 100% of nose low launches. To this day, I have not met
an individual who can run 40 mph for launch.
You may have guessed by now that I am a propnent of the "nose high" launch.
What do I mean by "nose high"? I approach most of my launches, by holding
my nose at an angle of attack (it will be an angle of attack when
I start to run, anyway) that will match my launch speed. Nearly all "advanced"
pilots I have run across believe I am launching with my nose too high. If
they don't know me, they will offer their knowledgable assistance and ask
me to lower my nose, or I will stall on launch. Ah... enter Myth #1.
Will starting your launch with your nose "high" cause you to stall?
It is, indeed, the popular belief that starting your take-off run with your
nose high, will inevitably result in a stalled launch. This is untrue. It
is true, of course, that you will stall your launch if you push the
control bar during the take-off run. But this is different than starting with
your nose high and allowing the glider to seek its own angle of attack during
the take-off run.
Pat Denevan, a world renowned and well respected hang-gliding instructor,
teaches a launch method to both beginning students and advanced pilots taking
his "Launch and Landing clinic" which includes a crucial component: Tow the
glider with the harness straps. In fact, if a pilot is able to tow the glider
with the harness straps and completely let go of the control bar, the glider
will seek the perfect take-off angle of attack with no input from the pilot.
This is easily demonstratable.
In fact, I often do a demonstration for disbelievers in the "nose high"
approach, as proof-positive that a successful launch can be accomplished with
the nose quite high. I approach the launch as I normally would, with the flying
angle of attack set to launching speed, then ask, "Is my nose too high?".
Most of the observers, used to a nose-very-low launch will nod their heads.
Of course, this prompts me to raise the nose higher. "How about now?" I'll
ask. I'll repeat this until my keel is on the ground and the basetube is
sitting directly in front of my eyes.
At this point, I'll lean forward and start to run with my hands by my side,
not touching the control bar. The glider will lift off the ground, the nose will
lower until the right angle of attack is attained, and I'll fly off the hill
with an adequate amount of flying speed.
Why does this work? Because I'm towing the glider with my harness straps for
the entire take-off run. Skeptics say this works because I am a talented
pilot who has been flying hang gliders for most of my life. However, I only
simply run in a straight line to take off. How much talent could there be in
running in a straight line?
If you think about this long enough, you'll realize that this is exactly how
paragliders take off. Imagine telling a paraglider pilot that he should hold
his glider's nose low before taking off!
No, launching with your nose high will not result in a stall. Its a myth!
A quick, multiple answer quiz, then:
- The best method for launching a hang-glider is to:
- hold the glider's angle of attack low and run hard, allowing the
nose to rotate up during the run.
- hold the glider's angle of attack at the proper angle of attack
for take off speed and do not alter the angle of attack during the
take off run.
- hold the glider's angle of attack higher than the proper angle of attack
for take-off speed and allow the nose to come down during the take-off run.
- On question #1, if it is not possible to get the angle of
attack exactly right, it is better to
- err on the side of having the nose too low.
- err on the side of having the nose too high.
I'm quite certain that the majority of readers would agree that the answer
to #1 is b. It just seems logical that having a constant angle
of attack during the take-off run is the correct approach. Again, though,
the take-off angle of attack is usually higher than most expect.
But what about question #2? Conventional wisdom would take the
"conservative" approach and dictate a as the correct answer, since it
adheres closer to our age old "nose low, run hard" take off technique.
However, there are actually advantages to having the nose high and detriments
to launching with the nose low. In fact, it takes a higher level of skill to
launch with the nose low, than it does to launch with the nose a little higher
than take-off speed angle of attack.
Let's analyze this carefully. At the begining of this article, we just
three important ingredients to producing a good launch:
- Pitch and roll control authority during the take-off run.
- Smooth transition from running to flying.
- Little to no change in angle of attack during launch.
Pitch and Roll Control Authority During the Take-Off Run
Hang-gliders are weight shift control aircraft. Even rigid wings like
Atos' style gliders use weight for pitch control. For the glider to be
controllable under weight shift, if must be carrying at least part of the
pilot's weight. If it is not carrying the pilot's weight it is very difficult
Prove this to yourself by practicing a ground run with your glider on a flat
or lightly sloped field. Do not hook in, but rather, run with the
glider, holding the nose low with your arms wrapped around the downtubes.
Have a friend run along side and momentarily pull down a side wire.
Experience, then, first-hand how much effort it takes to correct that
disruption in the take-off run. This is no different than what would occur
if a thermal got under that opposite wing during the first moments of
A pilot's harness straps must go tight at some point in the take-off run.
The moment this occurs, control of the glider shifts from brute force to
weight shift. When you hold the nose of your glider down during the
take-off run, you postpone the moment when your straps go tight. Until your
straps go tight, you do not have weight shift control over the glider.
Everyone should agree on the fact that a hang-glider must accelerate forward
during launch, going from a speed below what is adequate for flying to or
beyond a speed that is adequate for flying. The right way to accomplish this
acceleration is to do so by shifting one's weight forward, relative to the
CG of the glider. This is what occurs when one "tows" the glider with one's
harness straps. But this cannot occur until the straps are tight. Nose high
launches ensure that that the harness straps are tight as early as possible.
Once the harness straps are tight, by all means, pull in to accelerate the
Note also that, not only can the glider be accelerated by shifting the weight
forward, but it can also be controlled laterally because it is carrying
weight, which can be shifted to compensate for changes in roll during launch.
Contrarily, if the nose is being held down, and a thermal gets under one
wing, the glider must first lift high enough to allow the harness straps to
go tight before weight shift correction can occur. During the time it takes
for the glider to lift high enough to tighten the straps, precious
milliseconds have been lost in lack of control.
Allowing the nose to begin at a raised angle of attack, ensures that the
harness straps go tight early in the take off run and provides the launching
pilot with weight shift control for the largest percentage of time in the
Smooth Transition to Flying
The speed at which a hang-glider stalls goes up with increase in weight it
is carrying. So, while standing on launch, preparing to run, the glider has
the ability to carry as much weight as is comensurate with the wind (its
current airspeed). As you add speed in the take-off run, the glider gains
ability to carry more weight. Ideally, if we were to graph a glider's
stall speed, relative to the weight it carrying at any moment during the
take-off run, we would hope to see the airspeed at some margin greater than
its stall speed.
Now, the term "smooth transition to flying" is a phrase that is
taken directly from the FAR Part 103, Pilot Proficiency standards, for a
beginner rating. It reads:
D. Launch unassisted showing:
- Agressive run, if foot launched.
- Good angle of attack and pitch control.
- Directional control.
- Smooth transition to flying, during launch.
Most pilots I have interviewed who are firm believers in the nose low launch
describe their take-offs like this:
"I hold my nose down so I can run hard and get up enough airspeed before leaving
What have they just described? The nose goes down, the run takes place, holding
the nose down, when some speed is achieved, then something happens and we are
in the air. What is that something that has happened to get us into the
air. If you've taken the time to observe launches, you'll realize that that
something hapening is the nose coming up. Analyze then, what is happening
with regard to the relationship between stall speed, glider airspeed, and glider
loading. If the nose is low during acceleration, the glider is carying little of
the pilot's weight, or it is carrying the pilot' weight on the downtubes where
he his holding the glider. Then, quite abruptly, the weight is transferred
from the pilot's legs, to the glider. This abrupt change, is _not_ a smooth
transition. It is, in fact, an abrupt transition. This is undesirable.
Enter myth #2.
Myth #2 is the interpretation of feeling that pilots get when being "tugged"
by the harness straps, that this is holding the pilot back from accelerating
forward in launch. When the nose is high and after a step or two, the "tug"
on the harness is interpreted as holding you back. The myth is that the
glider can, somehow, not be accelerated when this "tug" is occuring. This
is not true.
In fact, the difference between holding the nose low and using your legs and
a brute force grip on the control bar, to accelerate the glider forward, is
far more difficult than making use of gravity to accelerate the glider
forward. When a pilot is launching down a hill, each step is at a lower
elevation than the step before it. With each step, the nose-high pilot is
placing more weight on the glider. If the pilot is towing the glider, the
natural reaction will be for the glider to accelerate forward.
Personal opinion here, now. Item one on the Part 104 Pilot Proficiency for
demonstration of launches "Aggressive run, if foot launched", is perhaps
poorly worded. Perhaps, "confident run", or "assertive run", might be more
appropritate. A properly executed launch, using gravity to accelerate the
glider can produce a perfectly clean and fast launch without agressiveness.
In fact, under some circumstances, one can turn a lumbering stride into long
steps while pulling in and have a take-off run that is more than adequate,
with plenty of speed building up due to pulling-in, towing with the straps
and gradual build-up of load on the glider. That is a smooth transition.
I have seen many cases of interpretation of "aggressive run" as short, fast,
choppy and sometimes violent steps during take-off. This is very detrimental
to doing a good launch, because the focus is on the run, and not on the
acceleration of the glider. One does not necesarily result in the other.
Little to no change in angle of attack during launch.
From our quiz above, the ideal launch is one where the angle of attack is set
for adequate take