setting and letting the glider stall to the ground. Raising the hands too high on the control frame uprights.
They should be in the area of the weak links. Be cautious of going to the uprights by moving one hand
first and then pulling yourself up with that hand. It's easy to cause large oscillations this way.
Important:
After setting the flaps for landing, throw the rope over the control frame to help prevent the
inadvertent release of the flaps.
General comments
It is extremely important for maximizing your flight performance that you have a good airspeed indicator
and understand your polar and speed ranges. For a pilot of approximately 200 lbs hook-in weight with
clean harness and good flying posture, most competitive pilots assume a minimum sink rate of 135 ft/m at
23-24 mph and sink of 400 ft/m at 42 mph. Best glide occurs around 32-34 mph with 5° of flaps. All of this
varies by altitude, temp, amount of dirt on the sail, etc. Experiments with a good flight computer will
continue to improve your results.
Adjustment of the trim speed
The optimal trim speed lies between the speed of minimum sink and best glide. Slower will give a more
comfortable thermalling position but leave you at higher risk of stall, and conversely for a higher trim
speed. The most practical combination to begin with is trim speed of 28-30 mph with 15° flaps. This keeps
you in the middle of the range with a slight speed bias for safety. There is not much sink difference
between 24 mph and 28 mph. Most pilots will find it advantageous to have the extra control afforded by
the extra airspeed.
Never adjust the trim setting more than ¼ of an inch at a time without flying the glider. Small changes will
produce significant differences in trim.
Warning
Most of the ATOS is made of carbon fiber materials. These materials show a different breaking behavior
to aluminum and steel. Most metallic materials permit some damage recognition due to their behavior of
deformation. Carbon is extremely stiff and its failure mode is to shatter. From an extreme overexertion,
carbon cloth can exhibit not much more than a barely recognizable crack! Other methods must be used
for damage recognition, e.g. by checking rigidity, by observing cracking in places with stress
concentrations, a delamination in the layers (bouncing a coin will often expose this). If you have had an
extreme landing or other incident, be sure to remove the sail and inspect the area or consult your ATOS
dealer.
A Bi-Annual Inspection should be performed by a Certified Dealer every 2 years or 200 flying hours. Up to
then it is essential for you to accomplish the following maintenance work. If any ambiguity should arise,
contact the manufacturer or your ATOS dealer.
Adjustment of the spoiler ropes
The spoiler ropes are adjusted at the factory so the control frame can be moved approx. ½-1" to each
side without spoiler deployment. This should be examined before each flight. Raise the nose with one
hand and move the control frame slightly - there should be 1-2" of movement without spoiler movement.
Another (perhaps better method) is to have someone hold the keel level while you hold the wing level.
You should be able to move one wing tip up or down 6" without either spoiler deploying. This allows
straight flight without the spoilers working too often. Too much movement before spoiler deployment
makes for a sloppy feel. After the first few flying hours the knots and also the rope will tighten and stretch
requiring adjustment.
