User Manual ATOS C
Version: 29.01.2002 English
translation: 9 August 2002 by Heiner Biesel
Please read before flying!
Congratulations on your purchase, and welcome to the ATOS
world! Your ATOS C is a high performance glider. To fully exploit its
capabilities while remaining well within safe limits, you should become
thoroughly familiar with the contents of this manual. If you have any questions
or need support, do not hesitate to contact the A.I.R. Team.
Your A.I.R. Team
Version: 01/02
1. Transport
·
By car
The carbon
fiber D-tube can be damaged by point loading. For safe transport the glider
should always be supported by a large padded area. A ladder with several padded
steps is one possibility. If the D-tube is supported at only two places, these
supports need to be padded at least 4 inches in length, and wide enough to
support the full width of the glider. Anything less is likely to result in
transport damage, which can seriously reduce the strength of the main spar and
the entire D-tube.
Do not tie down
the glider too tightly, and use wide tubular of flat webbing to minimize point
loading. If the glider is likely to get exposed to rain, and especially to salt
water, a watertight cover bag is strongly recommended. If the ATOS C gets wet,
dry it as quickly as possible to avoid staining the sail, or causing corrosion
of the metal parts. Exposure to salt water should always be followed by a
thorough rinse in sweet water. The carbon fiber parts do absorb a small amount
of moisture, and should be dried as soon as possible.
·
By ski lift or cable car
The same
considerations apply, except that additional padding is usually required.
A.I.R. sells a watertight cover bag, which includes padded supports which can
be velcroed to the cover bag at the required points. During flight they can be
stowed inside the D-tubes of the glider.
2. Setup
1.)
Avoid laying the D-tubes on rocks or
uneven ground. If this cannot be avoided, consider placing the nose on
something soft, like a harness, or some padding. Remove the base bar from the
D-tube where it is stored.
2.)
Connect the downtubes to the base
bar. Careful, don‘t drop one of the downtubes; doing so can damage the D-tube
or one of the ribs.
3.)
Put the ATOS on the control bar,
making sure it is stable. If it should fall over, the D-tube or the fittings
that attach the downtubes to the keel can be damaged.
ATOS
standard control bar
4.)
Remove all parts stowed inside the
D-tubes. Place the tip extensions and tip wands close to the tips of the wing.
5.)
Open up the two
halves of the nose lever as shown.
The wing can be
damaged if this is not done before
the wings are
spread.
6.)
Spread the wings far enough apart
for the keel to touch the ground.
7.)
Hook the sail to the keel using the
rings at the trailing edge. The keel can be moved a little from side to side to
make this easier. Avoid large displacements as these could damage the flaps.
The flaps must be behind the downtubes before the sail can be connected to the
keel.
8.)
Close the top zipper.
9.)
Tighten the nose lever and safety
the pip-pin. Use the nose tube as a lever, if necessary. Make sure the wingtips
are as far forward as possible, otherwise excessive force may be necessary on
the nose lever. Hook up the front cables.
10.)
Insert nose tube until the catch
engages the hole in the keel.
11.)
Insert the keel stinger.
12.)
Insert the tip extensions until they
are fully seated. This is best done by opening the velcro between the last two
ribs and folding the sail back to fully expose the end of the D-tube. The
D-tube and the sail can be damaged if the tip-extensions are not completely
inserted. Place the carbon inserts on the velcro of the tip extensions, edge
even with rib 9.
13.)
Open the velcro at the tip of the
sail and insert the tip wand all the way into the hole of the tip extension.
The slot at the end of the tip wand should be roughly parallel with the
trailing edge of the sail.
14.)
Tighten the tip wand.
15.)
Tighten the ribs starting from the
end of the wing. After tightening rib 6 you should attach the spoileron lever
to the spoileron surface by means of the provided bungee loop. The ribs are
tightened by fully inserting the metal fitting on each rib, and only then turning them with thumb and finger of one hand. Do
not push or pull on the rib with your other hand, this runs the risk of
damaging the rib. If the sail is tight and you cannot exert enough force on the
rib fitting, you can use your other hand to push only on the very end of the
rib. Gloves help! An optional tool is
available which greatly reduces the effort required to tighten the ribs. Be
careful when using this tool, it is possible to exert too much force and to
break ribs. The tension at each rib can be adjusted by moving the velcro
attachment of the rib fittings. It is recommended to adjust the tension after
about 10 hours of flight, or whenever there are great changes in climate. Rib
number 6, the spoiler rib, is especially critical in this regard. Ribs 7 and 8
should be as tight as practical so that the sail will remain clean smooth at
high speeds.
The picture to
the right shows the use of the
optional tool
for tightening the ribs.
16.)
Attach the
spoileron to the actuating lever.
17.)
Attach the flap control cable via
the pins to the rear of the flaps.
18.)
Attach the control cables. Make sure
that rib 6 is fully tightened at this point, otherwise the sail or the D-tube could
be damaged.
19.)
Pull the flap cable through the
catch on the base bar.
20.)
Close the lower zipper.
21.)
Attach nose fairing, making sure it
makes a clean connection with the velcro.
3. Breakdown
1.)
Disconnect the spoileron cables.
2.)
Disconnect the flap cables.
3.)
Loosen the ribs, starting with the innermost
ribs. Rib 8 must be folded inward toward the keel, unlike all the other ribs.
In order to do that, rib 7 has to be turned toward the keel far enough for rib
8 to clear it. Once rib 8 has been folded inward, rib 7 can be folded outward.
4.)
Remove the tip wands and tip
extensions.
5.)
Fold the sail around the D-tube from
the front. Stow the tip lever inside the sail. Slide tip cover bag over the
sail.
6.)
Pull out the stinger.
7.)
Remove the nose cover and carefully
loosen the nose lever. Make sure the stinger has been removed, otherwise the
flaps could be damaged.
8.)
Open top and bottom zippers, and
place the zipper pulls at the trailing edge of the sail. If the pulls are left
at the front they can be damaged when the glider is folded up.
9.)
Fold the top zipper back toward the
wing tips to avoid crushing it between D-tube and keel.
10.)
Attach padding for downtubes on the
controlbar-keel junction.
11.)
Fold the D-tubes toward the keel.
Make sure that the control cables have been detached. If they are not, the
D-tube and the sail can be damaged.
12.)
Stow the tip extensions, tip wands,
stinger, and nose tube in the D-tube.
13.)
Place the cover bag over the glider,
starting from the nose.
14.)
Turn over the glider and place
carefully on the ground. This is best done by lifting the D-tubes with one hand
while rotating the glider with one of the down-tubes.
15.)
Slide the base bar into the left
D-tube.
16.)
Place flaps and spoilerons flat on
top of the D-tubes, white (top) side against white side. Make sure that the
spoilerons do not extend beyond the sides of the D-tubes.
17.)
Place the nose cover on the flaps.
The carbon inserts can be placed over the outside of the D-tubes in the tip
area. Make sure that the profile of the inserts matches that of the D-tube. Zip
up the cover bag.
4. Flight
characteristics
·
Start
The ATOS C is
statically slightly tailheavy. After a few steps it will stabilize in a neutral
attitude. During the first few steps it
is important, however, to keep the nose low. Generally it is better to keep the
nose lower than optimal. This makes the glider less sensitive to side gusts and
keeps the wingtips further off the ground.
It‘s a good idea to
do some running on flat ground to get a feel for the behavior of the wing prior
to the first flight. The highly effective spoilerons make it possible to keep
the wing stable and steady even during gusty launch conditions.
For normal
starts the flaps should be deflected about 15°. Launch technique is similar to
that for high performance flexwings.
·
Flight
The ATOS C is
controlled purely via weight shift. Pitch control is exactly the same as on any
flexwing, while roll is controlled via spoilerons, which are actuated through a
horizontal shift of the pilot‘s body. The forces needed to control the ATOS are
considerably less than what a normal flexwing The glider is quite stable in all
three axes and requires little high-siding in turns. Unlike a flexwing, the
ATOS does not react to short control impulses. A properly flown turn requires a
slight pull-in on the control bar, since the spoilerons create a small amount
of pitch-up when they are actuated. It is possible to lose a significant amount
of airspeed if one flies a series of roll reversals without paying attention to
airspeed.
Spoileron actuation
of 50% or more creates a strong yaw moment, which can be advantageous when
entering a thermal, for example. Higher speeds can cause excessive yawing which
can lead to PIO yaw oscillations in turbulent air. Such oscillations dampen out
quickly if the pilot avoids any roll input to the glider.
Above 40 mph and
with flaps at 70°, or above 45 mph with flaps at 0° to 15°, pilots should use
reduced control inputs. These speeds are reached when the base bar is roughly
even with the stomach.
In order to verify that the trim speed is correct, and
that the glider does not exceed Vne an airspeed indicator should be carried on the glider.
Do not attempt to
spin the ATOS C! Spins can cause the glider to exceed its design load limits!
Spin Prevention:
Incipient stalls can be stopped by
centering and pulling in slightly on the control bar. Depending upon the
hang-point position and the height of the pilot, a stall can begin when the
base bar is pushed ahead of the head of the pilot. While thermaling in smooth
air the base bar will normally be between the eyes and the nose of the pilot.
·
Thermaling
For normal
thermaling 15° of flaps is optimal. Larger thermals or broken lift often
require flatter turns and less flaps. In turbulent air 5° of flaps works best,
since this permits higher speeds.
Above 40 mph
the best L/D glide is achieved with a flap setting of 5°. With this flap
setting the glider reaches its best L/D at around 33 mph, and even at 40 mph
the L/D has not deteriorated significantly. In light sink one should not fly
any slower than 40 mph.
·
Landing
The flaps should be fully deflected prior to landing,
since the glider has the lowest stalling speed at this setting. The glidepath
can best be controlled by varying airspeed, rather than flap setting. For first
landings we recommend pulling full flaps at 150 feet and flying a long final
leg. The flare window is comparatively large. Best landings are achieved by a
strong flare late in the landing phase.
Typical mistakes: Flying the final leg too fast
combined with roll inputs, which creates strong yaw movements. Flap adjustment
during the landing phase without paying attention to the actual landing point.
Getting too slow when going upright on the downtubes. The hands should be no
higher than the midpoint of the downtubes, so that it is still possible to pull
in on the control bar to increase airspeed if needed.
Tip: To keep the flap control cable from coming loose,
throw it over the front of the base bar. This keeps it out of the way, and even
an accidental pull on it will not pull it out of the cleat.
·
Winch
towing
A flap setting of
15° is optimal and permits good speed control. In addition, the glider will
reach its maximal towing altitude at this setting. It is essential to maintain
adequate airspeed by keeping the base bar roughly even with the head of the
pilot. Flying slower results in less altitude gain, and less speed reserve. A
stall on a winch tow is a very dangerous event and requires quick and correct
action!
·
Aerotow
15° flaps are optimal
with no head wind. With increasing headwinds, lower flap settings are indicated
(5°). The ATOS will be more stable at lower flap settings, and the trim-speed
of the glider is higher. Important:
Avoid flying below the towing aircraft! The downwash from the towplane can
cause a very strong pitchdown moment. This is especially true for trikes.
The ATOS C lands
easily even with the flaps undeployed. This is especially useful if one
experiences a weak link break at low altitudes. Concentrate on airspeed and
glidepath, and don‘t worry about the flaps if you experience a line break
shortly after launch.
·
Adjusting trim speed
Optimal trim speed lies somewhere between minimum sink
speed and best L/D speed. The glider should trim to approximately 30 mph with the
flaps fully retracted. Slower trim speeds mean that the glider could be easily
stalled by pushing out minimally on the control bar. For initial flights we
recommend a higher than normal trim speed.
The glider will trim about 3 mph faster if the cover bag
is stowed in the D-tube during flight, which corresponds to moving the
hangpoint forward about ½ inch.
Trim speed can be adjusted by moving the hangpoint. It
is best to move the hangpoint no more than ½ inch at a time. If the velcro no
longer holds securely, it is very important to replace both the hangloop and
the velcro on the keel. Otherwise, trim speed and handling could change in
flight.
5. Maintenance
The composite
materials used in the construction of the ATOS C wear and break quite differently
from conventional metals. Aluminum and steel are ductile and show
characteristic deformations when they are damaged or overstressed, although
metal fatigue due to repeated loads beyond the elastic limits of the metal can
create very small cracks that are very difficult to detect.
Composite
materials generally do not deform if they are overstressed. Other means of
determining damage include visual inspections at points of high load
concentration, signs of delamination, or testing the stiffness of a component
by applying a load to it. These methods of inspecting composite structures
require some skill and experience. For this reason we recommend an inspection
by an ATOS dealer if there is any possibility of damage to critical components.
A dealer
inspection is required every 200 hours, or two years, whichever comes first.
The following maintenance items should be completed by the owner. In case of
questions, please contact a dealer or the manufacturer.
·
Adjustment
of the control cables
The factory adjusts
the control cables to have about ½ inch of play to either side before the
spoilerons are actuated. This should be checked before every flight by lifting
the nose and moving the control from side to side.
During the
first few hours of flight there is some stretching of the cables. This does not
affect the safety of the glider, but if there is more than an inch of slack the
cables should be adjusted. This can be done via the adjustment screw on each of
the spoiler levers.
Whenever the
spoiler cables are adjusted it is essential
that the stop cable be adjusted as well.
·
Function
of the stop cable
To avoid damage to
the spoileron rib and lever, the spoileron cable has a stop. This consists of a
cable between the spoileron cable and the keel, which limits the travel of the
spoileron cable.
·
Adjustment of the stop cable
The spoileron
cable must be able to produce a full 80° of spoileron deflection. At this
deflection the stop cable should be taut. If the stop cable is too short it
will not be possible to achieve the full spoileron deflection, reducing roll
control authority.
Adjust the
length of the stop cable to provide about 80° spoileron deflection, and check
before every flight.
·
Cable
replacement
Spoileron cables must be replaced every 200 hours, or
every two years, or whenever they show any visual wear or damage. The spoileron
steel cables which connect to the control frame, and which double as front
control bar cables, must be replaced every 100 hours, and should be checked for
wear and function prior to every flight.
·
Checking
the pulleys
All pulleys
should be checked for wear and damage. They should turn freely, and without
play or noise. Check all of them at least every 50 hours.
·
Checking
the ribs and rib tighteners
Ribs can be checked visually, and by touch. Squeezing
the rib can show weak or damaged areas, either through a characteristic
crackling sound, or via a deflection of the material.
The connections between the ribs and the D-tube should
be checked especially carefully by pushing the end of the rib up and down a
bit. Again, sound and deflection can indicate some damage.
Rib 6 also holds the spoileron lever, and should be
checked especially thoroughly. Look for any damage to the lever or its
attachment to the rib.
·
Ribs
and tip wands
Check the outer
ribs and the tip wand if they have contacted the ground during a landing.
·
Control
bar attachments
The bolts which attach the downtubes to the keel
should be checked and lubricated ever 50 hours or 20 flights.
·
D-tubes
The D-tubes can
be easily damaged through point loading, either during transport, or if they
are placed on rocky ground. Damage to the leading edge nose section of the
D-tube can be detected by running your hands over the D-tube and feeling for
dimples, dings, soft spots, or depressions. Minor damage in this area can often
be repaired by epoxying a carbon fabric patch over the spot after filling the
area with an epoxy-microballoon mixture. Contact your dealer for help.
However, damage
to the D-tube in the area of the spar, or anywhere along the innermost 5 feet
of the D-tube, may require a complete replacement of the affected D-tube. Only
a dealer or the factory can determine if the D-tube can be safely repaired in
these areas, or whether a replacement D-tube will be required. Crashes which
cause major damage to the keel, or transport which may have created heavy point
loads to the D-tube, also require an inspection by a dealer, even if there is
no immediately apparent damage to the D-tubes.
·
Tip
wands and rib tighteners
If the sail has
gotten loose the cord at the tip wand can be tightened, as can the rib
tighteners. Adjustments may be necessary after the first few hours of flight.
Damaged cables, cords, or webbing should be replaced as soon as it is detected.
Pay special attention to rib number 6, which holds the spoileron lever, and to
the tip wand cords.
·
Sail webbing
It is essential
that the webbing, which attaches the rear of the sail to the keel, be taut when
the wing is fully set up. Loose webbing means that the wing will not have the
correct sweep, and the CG will be off, both of which will affect flying
characteristics and safety.
Wing sweep
should be checked every ten flights, or whenever temperature and humidity could
affect the sail. To check the sweep of the wing, attach a thin cord or string
to the rib tighteners of the outermost ribs. This string should cross the keel
at the hole, but in no case more than ½ inch ahead or 1 inch behind this hole,
when the keel is held horizontally. If this is not the case, adjust the webbing
at the keel to produce the correct wing sweep.
·
Flap
cord
Check the flap cord
every ten hours. The attachment points between the lines and flaps are
especially vulnerable to wear and damage, and should be checked often.
·
Flap
bungee
Replace the
flap bungee if it has weakened to the point where the flap will not fully
retract when there is no tension on the flap cord.
It is possible,
however, that the bungee is strong enough, but the velcro attachment between
flap and the lower sail is too tight. Loosening this attachment and moving the
flap further back can correct this problem. It also possible to tighten the
bungee at the point where it attaches at the front end of the keel.
·
Sail
After extended use,
all seams, straps, and attachments of the sail should be visually inspected.
The zippers should move freely. Storage in a dry, cool place, and minimal
UV-exposure increase the life of the sail. If necessary, tighten the webbing
which attach the sail to the keel.
6. Storage
7. Flight
limits
Vne with 0 - 15° flaps 50
mph
Vne with 70° flaps 50
mph
Maximum positive load +4g
Takeoff weight range 90-152
kg
8.
Specifications
Span: 42
feet
Aspect ratio: 12.1
Flap range: 0
- 70°
Wing area: 146
ft2
Weight: 77
lbs.
(Weight is approximate due to the use of composite
materials)
We are happy to answer your questions and appreciate tips and
suggestions about our products. Additional information can be found on our
website http://www.a-i-r.de/
The A-I-R team hopes you will enjoy many pleasant and safe flights on
your ATOS.
A-I-R GmbH & Co
Borsigstr.17 D-71277 Rutesheim
Tel.: +49 (0) 7152 351 251
Fax: +49 (0) 7152 351 252
www. A-I-R.de