Figure 5-14. Rotating the wing onto its control frame.
Figure 5-15. Placing the front wires at the control frame.
Figure 5-16. Removing the straps holding the two wings together.
Figure 5-17. Wings spread slightly to raise the kingpost.
Figure 5-18. Pads and wing tie straps neatly rolled into wing cover
bag.
carefully and evenly. Do not force anything. Ensure the wires
are not wrapped around anything. Separate the right and left
battens. Separate the straight battens (for a double surface
wing) and set them to the side. Lay out the battens, longest
to shortest from the root to the tip next to the pocket they
any wing it is a good idea to take pictures, draw sketches, or
take notes regarding protective pad location so they can be
put back in the proper location during take down.
Assemble the triangular control frame without attaching the
wires to the nose. [Figure 5-13] Rotate the wing up onto its
control frame. [Figure 5-14] Place the front wires near the
control bar so no one walks on them, remove, and roll up
the cover bag. [Figure 5-15] Release the wing tie straps that
are holding the leading edges together. [Figure 5-16] Spread
the wing slightly. Remove the pads from the wing keel and
kingpost. Note the protective pads still on the wing tips
protecting them from the ground during most of the wing
set up procedure. [Figure 5-17] Continually manage the
wing pads and wing tie straps by rolling the pads into the
cover bag so they do not blow away. [Figure 5-18] If the
kingpost is loose, insert it onto the keel to stand upright. If
the kingpost is attached, swing it upright. Topless wings
have no kingpost. Spread the wings as necessary to keep
the kingpost straight up, [Figure 5-19] spreading them out
Figure 5-23. Wing ready to tension.
Figure 5-22. Attaching double pull batten (inset). Batten secured
into batten pocket.
Figure 5-21. Inserting batten into batten pocket.
Figure 5-19. Raising the kingpost and spreading the wings as needed
to keep the kingpost upright.
Figure 5-20. Wings spread and battens organized to insert into
wings. Note small stepladder holding up keel.
go into on both sides. Note the protective pads are still on
the wing tips so they are protected. [Figure 5-20] Insert the
battens into the batten pockets, starting at the root and work
out to the tip. [Figure 5-21] Most batten attachments are
double pull. [Figure 5-22] Some manufacturers use cord or
elastic, and others use a system that slips into the sail itself.
See the POH for wing details. Insert battens from the root
towards the tip about ¾ the way out on each side. Leave
the tip battens for later. Spread the wings as far as possible.
[Figure 5-23] Check to ensure all the wires are straight, not
wrapped around, and clear to tension the wing. Tension the
wing by pulling back on the crossbar tensioning cable and
pulling the crossbar back into position. This may require
signifi cant effort for some wings. Secure the tensioning
cable to the back of the keel. [Figure 5-24] If the keel does
not extend out, then support the aft end of the keel to lift the
tips off of the ground. [Figure 5-25] Move to the front and
secure the front control frame fl ying wires to the underside
nose attachment. [Figure 5-26] Remove the tip bag protectors
and install the tip battens, continuing to move from the root to
the tips on each side. Insert the washout strut into the leading
edge. Each manufacturer has its own washout strut systems
and tip battens. Some manufacturers have no washout struts.
Refer to the POH for wing specifi cs. [Figure 5-27]
Figure 5-24. Attaching the tensioning cables to the back of the wing
to complete the wing tensioning step.
Figure 5-25. The wing tensioned.
Figure 5-26. Attaching the front flying wires to the nose
attachment.
Figure 5-27. Installing the wing tip battens.
Figure 5-28. Installing the lower surface battens.
Figure 5-29. Attaching the mast to the wing after checking the POH
for the proper hang point location.
Insert bottom battens for a double surface. If inside a hangar
where there is no wind, this can be done by putting the nose
down, making it easier to install the lower battens. [Figure 5-28]
If not already accomplished, lift up on the back of the keel
and put the wing on its nose. Lower the undercarriage mast
and line up the undercarriage behind the wing exactly in the
middle. Move the undercarriage forward and attach the mast
to the proper hang point location on the wing keel. Consult
the POH for the proper hang point for desired trim, speed,
and loading at this time. Attach the backup cable at this time
also. [Figure 5-29]
Figure 5-33. Installing the seats.
Figure 5-32. Attaching the front tube.
Figure 5-31. Lifting the wing up into position.
Figure 5-30. Wing in position and carriage chocked to lift the
wing.
Lift up the nose and let the carriage roll backward until the
wing is level and the control bar is in front of the front wheel
of the carriage. Engage the parking brake and chock the back
of the carriage wheels. Ensure everything in the fl ight deck is
free and clear so the wing can be lifted freely into position.
[Figure 5-30] Lift the wing into position and lock the
carriage mast. This position is unique to each manufacturer
as some masts hinge above the fl ight deck. Refer to the POH
for details on a specifi c aircraft. [Figure 5-31] Install the
carriage front tube. Secure the control bar to the front tube
with a bungee. [Figure 5-32] Attach any fairing or seats as
required. [Figure 5-33]
An alternate method of setting up the wing is to do so on the
ground. This is not preferable because the sail is susceptible to
getting dirty. However, this method could be used for setting
up wings if it is windy or if recommended by a particular
manufacturer. The ground method steps are the same as
those in the assembly procedure except after the control bar
is assembled, the wing is rolled over so the control frame is
under the wing. The wing is assembled as if it were standing
on its control frame. After the wing is tensioned, the nose is
lifted, the control frame pulled forward, and the nose wire
secured. This is not a common practice, and the POH should
be reviewed for details on this method if it is allowed by the
manufacturer.
Taking Down the WSC Aircraft
Find a suitable area to take down the wing, preferably grass,
cement, or pavement out of the wind. The best place is in
a large hangar so no wind gusts can affect the takedown. If
outside, align the wing perpendicular to the wind.
Figure 5-34. Padding the keel and kingpost with the right hand sail
over the top of the leading edge.
Figure 5-35. Left hand side rolled up and secured with wing tie.
Rolling right hand sail which will also be secured with wing tie.
Figure 5-36. Securing both leading edges together so the wing
easily fits into the bag.
Figure 5-37. Control bar folded down along leading edges but
wires not yet organized.
It is important to note that during the take down process, all
protective pads must be put in the proper place so that no
hardware can rub against the sail or frame during transport.
The POH should specify what pads go where. Overall,
pad everything along the wing keel plus the kingpost to
prevent cosmetic and/or structural damage occurring during
transport.
Taking down a WSC aircraft is done in the reverse order of
assembly with the following additional steps provided to get
the wing neatly packed and organized into the bag. After the
wing is detensioned and the battens have been removed from
the wing, keep the right and left battens separate for easier
sorting during the next assembly.
Carefully bring the wings in towards the keel and pull the sail
material out and over the top of the leading edges. Lower the
kingpost and pad it top and bottom. This is also the time to
pad the area underneath where the control frame is attached
to the keel and where the wires are attached to the rear of
the keel. [Figure 5-34] Bring the leading edges to the keel
and keep the sail pulled out over the top of the leading edge,
roll it up, and tuck the sail into the leading edge stiffener.
Fasten around the leading edge with sail ties. [Figure 5-35] It
is best to take one sail tie and secure the two leading edges
together so it fits into the bag. [Figure 5-36] Continue with
the reverse order (bag on, flip wing over, and disassemble
control frame at downtube and control bar junction). After
the control frame is disassembled and laid flat along the wing
as shown, the wires are not organized. [Figure 5-37] Pull
the cables forward towards the nose and organize them so
they are straight. Install the protective control frame pads
and carefully zip up the bag while tucking everything in so
there is no stress on the zipper. [Figure 5-38]
Figure 5-39. Left hand wing tip twist adjustment shown without
sail.
Sail Tension Markers
For more twist, rotate up
For less twist, rotate down
Wing Twist Adjustment
UP
DOWN
Figure 5-38. Carefully zipping bag with minimum stress by tucking
in wires and organizing components.
Wing Tuning
Wings are designed to fly straight with a range of trim speeds
determined by the manufacturer. If the wing does not fly
straight or trim to the manufacturer’s specifications, it must
be tuned to fly properly. Any wing adjustment can change the
handling and stability characteristics of the wing. Each wing
is unique and the tuning procedures are unique for each wing.
It is very important to follow the specific tuning procedures
in the POH/AFM for the specific wing. The following are
general guidelines to understand the tuning process.
Tuning the Wing To Fly Straight
Wings may turn to the right or left (depending on which way
the propeller turns) at high power settings because of the
turning effect described earlier in the aerodynamics section.
If it does not fly straight for cruising flight, visually examine
for any asymmetric right and left features on the wing
before making any adjustments. Look for symmetry in the
twist angle. Inspect the leading edge for any discontinuities,
bumps, or an irregular leading edge stiffener. Ensure the
pockets are zippered and symmetrical on both sides. Ensure
the reflex lines are clear, straight, and routed properly. Check
the battens to ensure the right and left match (do not make
any adjustments in the battens initially because reflex may
have been added at the factory initially for tuning), and
ensure the battens match the manufacturer’s batten pattern.
Check the batten tension on both sides and the leading edge
tension to ensure it is symmetrical. If it is a used wing just
acquired, research the history of the wing to see what might
have happened which would cause it to not fly straight. For
new wings, contact the manufacturer for advice.
If these checks do not make the wing fly straight, then
adjust the twist in the wing according to the manufacturer’s
instructions. More twist on one side decreases angle of attack,
produces less lift, and will drop the wing, which makes it turn
in the direction where more twist was added. For example,
with an unwanted left hand turn, either decrease the twist
on the left hand wing (increase angle of attack at the tip) or
increase the twist on the right hand wing (decrease the angle
of attack at the tip).
Batten tension is one way of fixing very mild turns. Increasing
the batten tension at the tips especially decreases twist and
raises the wing. For normal mild turns, most wings have an
adjustment at the tip where you can rotate the wing tip around
the leading edge. This is the easiest and most effective wing
twist adjustment. [Figure 5-39] For some models, reflex at the
root can be adjusted on a side to adjust a significant turn. More
reflex on a side means wing up, similar to reducing twist in a
wing. As emphasized above, the POH for each manufacturer
must be used for adjusting twist for wing tuning.
Adjusting the tension on the leading edge is another method
of adjusting the wing twist. However, different wings will
react differently when tension is adjusted, so the POH must
be followed for a particular wing. Some manufacturers do
not suggest adjusting sail tension to adjust twist, but require
equal tension with other adjustments to remedy an unwanted
turn. For those wings utilizing asymmetrical sail tension to
adjust twist, the following information is provided. Adjusting
sail tension is most effective on slower wings with lots of
twist. Adjusting sail tension affects some high performance
wings differently, making it necessary to consult the POH.
However, on most wings, increasing sail tension at the tip
increases leading edge flex, resulting in more twist.
Tuning the Wing To Fly Slower or Faster
Most wings allow the hang point attachment to move forward
to increase trim speed and back to decrease trim speed.
If there is a situation where the hang point is at the most
forward position and the wing trims below the manufacturer
Figure 5-40. Laminated index cards are handy for checklists, and
sized to fit into the flight suit zippered pocket.
Figure 5-41. Registration and airworthiness certificates are required
to be in plain view.
recommended speed, or the trim speed is within 10 miles
per hour (mph) of the stall speed, an alternate method for
increasing the trim speed is needed. For this situation, the
twist must be reduced symmetrically to increase the angle
of attack on the tips so they provide more lift and lower the
nose for proper trim.
This can be done by pulling back more on the crosstube
tensioning cables which reduces the twist in the wing.
However, this procedure reduces the stability of the wing
and decreases the handling ability of the wing because it is
stiffer. This is a common adjustment for hang gliding wings
for inflight trim, however this adjustment should only be
made on WSC wings as specified in the POH for a specific
wing.
Raising and lowering the reflex lines affects airfoil reflex
and also changes the trim speed of the wing. Lower reflex
lines speed the wing up and make it less stable, raising the
reflex lines slows the wing and make it more stable. Some
manufactures have this as an adjustable setting which can be
varied during flight, other manufactures have this adjustment
where it can be made on the ground. Other manufactures
do not recommend this adjustment because it can lower the
certified stability of the wing.
Prefl ight Inspection
Each aircraft must have a routine prefl ight inspection before
fl ight. Use a written checklist during prefl ight and ground
operations to maintain an established procedure. [Figure 5-40]
A written checklist is required so nothing is forgotten. Ground
checklists include prefl ight preparation, prefl ight inspection,
occupant prefl ight brief, fl ight deck management, startup, taxi,
before takeoff, and aircraft shutdown. Be smart and follow the
regulations—use a written checklist. All checklists should be
secured so they do not fl y out of the fl ight deck in fl ight and
hit the propeller. Securing with zippered pockets and having
lanyards for the checklists is recommended. Manufacturers
of Special Light-Sport Aircraft (S-LSA) have checklists that
come with the aircraft. Pilots with an experimental aircraft
may need to develop their own.
Certifi cates and Documents
The fi rst step of prefl ight inspection is to ensure the aircraft
is legally airworthy which is determined in part, by the
following certifi cates and documents:
• Airworthiness certifi cate
• Registration certifi cate
• Operating limitations, which may be in the form of
an FAA-approved AFM/POH, placards, instrument
markings, or any combination thereof
• Weight and balance
ARROW is the acronym commonly used to remember these
items. The PIC is responsible for making sure the proper
documentation is on board the aircraft when operated.
[Figure 5-41]
Aircraft logbooks are not required to be on board when it
is operated. However, inspect the aircraft logbooks prior
to fl ight to confi rm the WSC aircraft has had all required
inspections. The owner/operator must keep maintenance
records for the airframe and powerplant. At a minimum,
there must be an annual condition inspection within the
preceding 12 calendar months. In addition, the WSC
aircraft may also need a 100-hour inspection in accordance
with 14 CFR part 91 if it is used for hire (e.g., for training
operations). [Figure 5-42] If a transponder system is used,
the transponder must be inspected within each preceding 24
calendar months.
Figure 5-42. Maintenance requirements for WSC LSA.
WSC LSA Maintenance Requirements
S-LSA-certified by FAA accepted ASTM consensus
standards
Annual and 100-hour condition inspection may be
performed by:
- LSA Repairman with Maintenance rating (120-hour course)
- A&P or FAA certificated repair station
Maintenance,* repair, and alterations may be performed by:
- LSA Repairman with Maintenance rating (as authorized
by manufacturer)
- A&P or FAA certificated repair station (as authorized by
manufacturer)
E-LSA including:
Ultralights/trainers transitioned to LSA that meet the criteria
of 14 CFR Section 21.191(i)(1)**
Manufacturer S-LSA kits that meet the criteria of 14 CFR
Section 21.191(i)(2) (not amateur built)
Converted from S-LSA that meet the criteria of 14 CFR
Section 21.191(i)(3) (see 14 CFR Section 41.1(b) for
servicing)
- Annual condition inspection may be performed by:
> LSA Repairman with Maintenance rating (120-hour
course)
> A&P or FAA certificated repair station
> Owner Repairman with Inspection rating (16-hour
course)
- Owner can be trained in his/her own aircraft and does
not need 100-hour inspection.
- Servicing, repair, and alterations may be performed by
anyone.***
Amateur built that meet the definition of LSA and criteria
of 14 CFR section 21.191(g)
Annual condition inspection may be performed by:
- Original builder gets Repairman certificate for that specific
airplane and can perform annual condition inspection:
- If owner was not original builder, Annual condition
inspection may be performed by:
> A&P or FAA certificated repair station or original builder
> Original builder
Owner can be trained in his/her own aircraft; 100-hour
inspection not necessary
Servicing, repair, and alterations may be performed by
anyone***
* Simple “preventive maintenance” as specified by manufacturer can
be done by the owner and operator of a S-LSA with a Sport Pilot or
higher certificate.
** 100-hour inspection if used for training, compensation, or hire
(if applicable) before January 31, 2010 (towing no end date) may be
performed by LSA Repairman with Maintenance rating, A&P or FAA
certificated repair station.
*** Maintenance is a common term, but it is not used here because the
FAA uses the word “maintenance” to refer to a specific level of service
required to be performed by properly trained mechanics.
The pilot must have in his or her possession a Sport pilot
certifi cate for the aircraft being fl own, medical eligibility,
and a government issued photo identifi cation. For a Sport
Pilot Certifi cate, medical eligibility can be a valid United
States driver’s license, which also serves as government
issued photo identifi cation.
To fl y the aircraft with Private Pilot privileges, the pilot
needs a valid FAA minimum third class medical certifi cate
accompanied by a government issued photo identifi cation
and Private Pilot certifi cate for WSC aircraft. See Chapter 1,
Introduction to Weight-Shift Control, for details on specifi c
pilot certifi cates and privileges.
Routine Prefl ight Inspection
The accomplishment of a safe fl ight begins with a careful
and systematic routine prefl ight inspection to determine if
the aircraft is in a condition for safe fl ight. The prefl ight
inspection should be performed in accordance with a printed
checklist provided by the manufacturer for the specifi c model
of the aircraft. However, the following general areas are
applicable to all WSC aircraft.
The prefl ight inspection begins as soon as a pilot approaches
the aircraft. Since the WSC aircraft can be transported by
trailer, fi rst and foremost, look for any damage that may have
occurred during takedown, loading, transit, unloading, and
setup. Make note of the general appearance of the aircraft,
looking for obvious discrepancies such as tires with low air
pressure, structural distortion, wear points, and dripping fuel
or oil leaks. All tie-downs, control locks, and chocks should
be removed during the unloading process.
The pilot must be thoroughly familiar with the locations and
functions of the aircraft systems, switches, and controls. Use
the prefl ight inspection as an orientation when operating a
particular model for the fi rst time.
The actual walk-around routine prefl ight inspection has been
used for years from the smallest general aviation airplane
to the largest commercial jet. The walk-around is thorough
and systematic, and should be done the same way each
time an aircraft is fl own. In addition to seeing the aircraft
up close, it requires taking the appropriate action whenever
a discrepancy is discovered. A WSC aircraft walk-around
covers four main tasks:
1. Wing inspection
2. Carriage inspection
3. Powerplant inspection
4. Equipment check
Throughout the inspection, check for proper operation of
systems, secure nuts/bolts/attachments/hardware, look for
any signs of deterioration or deformation of any components/
systems, such as dents, signs of excessive wear, bending,
tears, or misalignment of any components and/or cracks.