A-10A Build instructions. The A-10 Thunderbolt is also known as the

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A-10A Build instructions. The A-10 Thunderbolt is also known as the
A-10A Build instructions.
The A-10 Thunderbolt is also known as the Warthog, the 'flying gun' and the Tankbuster. Renowned
or feared for its formidable firepower, primarily the GAU-8/A Avenger, 7 barrel 30mm Gatling type
rotary cannon able to deliver up to 4200 rounds per minute! In addition there can be up to 16,000 lb
of ordnance between its 11 pylons. This aircraft was used extensively during Operation Desert Storm,
in support of NATO operations in response to the Kosovo crisis, in Operation Enduring Freedom in
Afghanistan and in Operation Iraqi Freedom.
The first flight of the A-10 was in May 1972, and a total of 713 aircraft were produced. The
production of A-10 aircraft came to an end in 1984. Originally manufactured by Fairchild, since 1987
the prime contractor for the A-10 has been Northrop Grumman.
Specification:
Span: 50” (130cm)
Length: 48’’ (125cm)
Approximate flying weight: 3lbs (1.2kgs)
Battery: 3s -4s 3000-4000 MaH LiPo
EDF: 2 x 64mm ADH300`s or GAD Viper-Tec`s
ESC: 2 x 25A-35A esc.
Servos: 2 x 5g servos for the rudders, 1x 9g servos for elevator and 2 x 9g for ailerons.
2 x 30cm Y lead & 3 x 30cm Extensions
Other equipment required to build this model:
Hot glue gun. (Stanley dual temp is best)
15W – 25W soldering iron and solder.
Epoxy.
UHU-por glue. (Recommended) Alternatives are: Aerobond, Evo-stik “Solvent free” adhesive,
copydex. Note. The adhesive must not contain solvents so if in doubt test on some scrap material.
Lightweight filler- Polycell “One Fill” or similar.
Length of thin cord around 30” (75cm) long. This is useful in achieving the correct line up of items in
the build.
Home- made sanding board to be made first. (At least A4 size, made from flat MDF etc with medium
sandpaper glued to it)
GAD run a website that has open forums covering many aspects of the product line such as
modifications, build tips, finishing ideas and tips and a wealth of experience.
It is found at: http://www.greenairdesigns.com click on GAD community, GAD’s new forum.
Don’t pass it by!!
The experienced builder will determine their own order for assembly of the model, so these
instructions are intended for the less experienced builder to follow a logical sequence of
building.
The sequence of build is: Tail assembly, Fuselage, Fan/ Engine pod assembly and fit, Wing,
Fixing of the flying surfaces to the fuselage, Undercarriage, Radio installation.
To avoid clutter on the work area it is advisable to keep the parts in the box and only take out
the parts to be worked with. This will ensure that parts not yet required do not get mislaid or
damaged.
Making the tail assembly
To assist with the elevator pushrod location later in the build it is suggested to build the tailplane first.
The first step is to laminate the fins and rudders so identify the eight parts that make the left and right
units. It may help to leave the rudder attached at this time but no matter if it has been separated. It can
be assembled later. The A-10 is characterised by its twin fin arrangement so it goes without saying
there is a left and right fin, so mark clearly on the inside faces which are left and right. Carefully
spread a thin layer of the UHU-por to each inside surface and leave until the surfaces turn tacky and
are then ready for bonding.
Due to the nature of these contact glues you only get one chance of joining them so make sure there is
good alignment of the parts before allowing them to touch. When ready bring the parts together on a
flat surface and apply gentle pressure from the centre outwards over the part to ensure a good bond.
REMEMBER. Check twice, glue once.
Repeat with the other fin and rudder ensuring it forms the opposite side. When completed the rudders
may be removed for ease of build. Here is where you breathe a sigh of relief that you have made a left
and right fin (Didn’t you)?
Installation of the rudder servos is next so take one of the 5g servos and offer in position in the lower
inside area of the fin as shown in the picture. Mark the outline of the servo and carefully cut away the
material until the servo lies flush with the surface. Allow space for the servo arm to move without
restriction.
Repeat the process for the other fin.
Take the tailplane and check the edges and surface for deformities and sand lightly to remove any
imperfections.
Cut a 6mm square slot for the aluminium reinforcement strip on the tailplane underside approximately
at half chord and fix in position with hot glue or epoxy if not that experienced with hot glue.
Just make sure that when you fit the stab, it mounted with the spar in the underside for best looks.
Offer the fin on to the tailplane and check that the fin is square to the tailplane vertically and trailing
edges are level to each other. Adjust as needed.
When happy with the fit glue the fins to the tailplane using hot melt glue or epoxy with the trailing
edges flat on the building table, ensuring the fins are 90̊ to the tailplane, and vertical. When the glue is
cured the tailplane can be turned over and the slots for the servo wires can be cut in to the tailplane
underside. The use of pre-made leads or extended home- made servo wires is the builders’ choice so
route the cables as shown to go forwards in to the forward fuselage.
Next in sequence are the rudders. Sand the rudders and fin edges as desired ensuring that the rudder
leading edges will allow unrestricted movement when hinged. Normally a bevel on the leading edge
as shown is sufficient. Fix the hinges in position. This can be easily achieved by drilling the locating
hole with a drill bit slightly undersized, and then making a small slot a few mm each side of the hole
along the hinge axis line. Test the depth and fit with a hinge and when satisfied apply some suitable
adhesive in to the locating hole and insert the hinge ensuring that the hinge axis is on the centre line of
the control surface.
When fitted they should appear as the picture above. The same procedure is used to make the
corresponding locations in the fin trailing edge ensuring that the adhesive used allows sufficient
working time to align all three hinges allowing full and free movement of the rudder. Repeat the
procedure for the other fin and rudder.
Next in line are the rudder pushrods and horns. Take both rudder pushrods (These are from 20swg
piano wire) and make a Z bend at one end to fit in to the servo arm.
Ensure the servo is centred then fit the wire to the servo arm and use the wire to show the best line to
the horn position.
Cut a small slot in the position shown in the picture to fix the rudder horn. Make sure the fit is snug
and push the horn in to position. This will assist in locating the position of the Z bend/ horn
connection. It is the builders choice to connect the surfaces now or later in the build.
If connecting now attach the horn to the control rod and fix in to place with a suitable adhesive
ensuring the rudder is not deflected. The servo can be fixed in with a small amount of hot melt glue.
Rudder Procedure:
Glue on rudders.
Glue in servos after centralising
Make control rods.
Slot horns
Adjust rods accordingly.
LAST:- Glue in horns with rudders straight with servos still centralised.
The elevators are prepared in a similar manner as the rudders and are top hinged to the tailplane using
Blenderm or dual filament tape (cowboy tape as we call it). Again, these are handed parts such that
the elevator tip is angled to allow for the rudder movement, the root is square to the fuselage.
The final action at this stage is to fit the elevator horns to the elevators as shown in the picture below.
We will come back to fitting & hooking up the elevators later.
Making the fuselage
The build commences with identifying the fuselage shells numbered 1-6. It is advisable to make sure
that the gluing surfaces match each other, and any surplus/ miss-matching material can be removed by
careful sanding on the sanding board. (The one you made earlier). When happy with the fit of the
parts continue by gluing each fuselage half shell to its corresponding shell with hot melt glue.
There are six half shells numbered 1-6 which make the fuselage sections F1 to F3. Any surplus glue
can be rolled off the foam surface by gentle rubbing with the finger. Wait a bit first to allow the glue
to cool a little as blistered fingers do not help to build an aircraft!
At the end of this stage you will have three nice tubes. The front section F1 can now be glued to the
centre section F2 ensuring first that the mating surfaces are both flat and square to each other. A
simple jig is a piece of thin cord taped to the end of F2 directly on the join seam. The two sections can
be placed together and held with a bit of tape whilst the cord is pulled taut over the seam at the end of
F1. If all is square the cord will lie directly over the seam. If not then carefully sand one of the mating
surfaces until the alignment is good. Make sure that the fuselage sections are in good line from the
side using the Mk1 eyeball and a bit of common sense.
Do not glue F3 to F2 yet as there is the elevator control rod and servo to fit in place.
The servo is fixed on to the underside of the fuselage section cross brace using hot glue. Test the
servo after fixing to ensure correct operation and cut away any foam that will interfere with the servo
arm movement.
The pushrod is made from 18 SWG piano wire with a Z bend made when the elevator is trial fitted for
length.
Recess both the elevators to take the carbon tube, slip on and well glue the horn, and make sure that
when gluing the carbon tube to the elevators that you get it completely sqr.
Put some masking tape over the general area of the pushrod exits so the exit positions can be placed
without leaving unsightly marks on the foam.
Insert the tailplane in to the rear fuselage section so that the height of the elevator horns can be seen.
Lay the completed pushrod over the fuselage section with the servo end in line with the servo arm,
and mark the general exit holes position with a vertical line. Tape the thin cord to the servo end of the
fuselage side in line with the servo arm. Tape the other end to the elevator horn and tighten gently so
that the elevator is level. Mark the intersection of the cord and the line drawn earlier on the tape and
that should be the pushrod exit position. Repeat for the other side. Cut out for the pushrod and open
out to allow the pushrod ends to exit as shown. Connect the servo to the pushrod and check that the
pushrod movement is satisfactory when elevators disconnected. When satisfied with the movement
remove the tailplane and set aside for later in the build.
The rear fuselage section F3 can now be glued to F1 and F2 ensuring that the fuselage sections are
straight and the tailplane mount is in the lower half of the fuselage section.
Form the nose block and fit to the front of the fuselage, making sure it is the correct way up. The
fuselage can now be sanded to remove any large irregularities in the joints.
Engine nacelles
Due to the long wingspan of the model it may be easier to build and mount the engine nacelles at this
point.
As shown in the steps above, glue the half sections of the inlet lip and rear duct together to form the
circular sections. Note that the inlet lip rests in front of the groove in the front of the nacelle body and
glue the inlet lip and rear duct to their respective positions on the nacelle bodies.
NOTE – The Thickest part of the nacelle centre section is mounted towards the fuse, which the pylon
glues to & the sweep is upward in the rear section and should be glued on so that the joint is vertical
to the aircraft or the thrust line be wrong!
STUDY THE 6 PICTURES ABOVE TO UNDERSTAND THE ORIENTATION OF THE GLUE
JOINTS & REMEMBER THEY ARE HANDED!!
The next step is to assemble the nacelle pylons using the UHU-por. Note that they are handed, with
the slot on the underside.
The nacelle pylons are each offered to the nacelle as shown and a cut-out is made in the nacelle body
half the depth of the pylon to accept the locating tongue. Repeat the procedure for the other pylon
making sure to make the opposite hand.
Cut a slot in the upper half of the nacelle body as shown ensuring a close fit to the pylon and lower
body. The fan unit can be placed in the nacelle with the intake lip resting in the groove at the front of
the nacelle.
Offer the ESC in to position on the underside of the pylon and mark the area to be removed. Carefully
cut away the material to hold the ESC with the heatsink part exposed to the airflow and a minimal
amount in the nacelle duct. Test the fan wiring via the esc to ensure the correct direction of rotation
and permanently connect to the ESC with the minimum amount of wire possible. The fan body and
ESC can be lightly held in place with hot melt glue. The top cover can now be fixed to the nacelle
body ensuring a good fit.
REMEMBER the ESC should be in the underside of the pylon with the heatsink exposed for cooling.
The thrust line is a critical part of the setting up of the aircraft so take care with the measuring. The
motor pylon leading edge aligns with the join of F2 and F3 so start by placing some masking tape
over the fuselage parallel to F2/F3 centred where the leading edge of the fuselage locating tongue will
rest. Put another band of tape across the fuselage centred over where the rear of the locating tongue is
positioned.
Ensure that the fuselage is straight and the seam is at top centre of the fuselage and measure back
from the F2/3 join the same distance as the front of the pylon to front of tongue and mark the tape on
the fuselage sides and top. Measure the distance between the front and rear face of the motor pylon
tongue and mark the fuselage where this rear point will lie. Draw a line between the three marks each
at the front and rear. (Shown in the picture above as a yellow line). Measure 29mm each side of the
fuselage seam on the front line (Shown as blue line) and mark the vertical line and repeat for the rear
line (Shown as green line), this time the measurement is also 29mm. This has located the top corners
of the motor pylon tongue location. Measure the thickness of the pylon tongue and mark the lower
corners of the tongue location (Red box section). Carefully cut out this rectangle ensuring that the
sides of the hole are perpendicular to the fuselage surface.
Offer in the pylon tongue and remove material to allow the ESC to locate in to the fuselage side (If
necessary). If the pylon tongue is inserted fully it should hold the nacelle and pylon perpendicular to
the fuselage surface. When satisfied with the fit extend the ESC wires (servo cables and power cables)
to reach the front of the aircraft. These can be threaded in to the fuselage and passed forwards and
finally the pylons can be glued in place using epoxy or hot melt glue.
Don’t forget to keep the pylons perpendicular to the fuselage as shown in the picture below.
If you haven’t done it yet, the tailplane can be fixed to the rear fuselage making sure that it is centrally
placed and perpendicular to the fuselage. Measure from the inside of each fin to the fuselage, and
mark the position prior to gluing with epoxy or hot melt glue. Carefully add a thin fillet of glue to
support the joint
Finally, hollow out the tail cone and fix in position on the rear fuselage not forgetting to make sure
that the elevator cross linkage does not bind and leave a small hole in the underside as shown in the
picture for the cooling air to exit.
Wing.
Take the 2 outer wing panels and place back to back and make sure they are the same size as
sometimes there is a little difference due to the cutting process. Sand the larger panel at the trailing
edge to match panel sizes and sand the thicker trailing edge to the same thickness.
Cut out the ailerons in the tips of the wing panels as shown. The measurements are: Span 220mm,
Chord 40mm and start 8mm in from the tip. Mark the ailerons and set the ailerons aside for fixing
hinges later.
Offer an outer wing panel to the centre section and check that they align well. Prop up the tip by 1 ½”
(38mm) and check that the root of the outer panel is parallel to the root section. Adjust by careful
sanding until the fit is good. The panels can then be glued together with epoxy or hot melt glue. The
same procedure is repeated for the remaining outer wing panel.
Turn the wing panel over and pack underneath so that the centre panel is supported along its span and
the tips are just touching the board as shown below.
Take the wing dihedral braces and mark a position half way along their lengths. Orientate the braces
so that the rounded section is pointing forwards. Bend gently at this mark until they achieve the
correct dihedral angle and lay flush with, or slightly below the wing surface.
NOTE- the picture shows a gap between the spars, YOU need to make sure they are touching and well
glued as you cannot see them once done.
The braces can then be glued in place with epoxy ensuring the dihedral is the same on each panel.
The wing tips are next, so locate two sets of depron tip profiles as shown. Again these are handed so
make sure to build a left and right hand set. The parts are best glued with UHU-por making sure that
the sections align along the top edge from front to rear.
These six stages show the makeup and profile of the wing tip. Final shaping, filling and finishing will
be done after gluing to the wing with epoxy or hot melt glue.
The aileron servo can now be fixed in the desired position in the main channel of the wing. Extension
of the servo cables is required to bring the connections to the Y lead and receiver.
Centre each aileron servo and carefully mark the arm position on the channel cover piece. Lay in
place over the servo to check the arm movement and open up the slot to suit. When satisfied with the
fit the cover can be glued in place with hot melt glue or epoxy. Repeat for the other wing panel and
finally close the centre section.
Shape the ailerons for top hinging and fix the hinges in to the top edge of the ailerons as were done
with the elevators. When happy with the hinge positions the aileron can be glued in position using a
suitable adhesive. Ensure the servo is centred then fit the wire to the servo arm and use the wire to
show the best line to the horn position.
Cut a small slot in the position shown in the picture to fix the aileron horn. Make sure the fit is snug
and push the horn in to position. This will assist in locating the position of the Z bend/ horn
connection.
It is the builders choice to connect the surfaces now or later in the build. If connecting now attach the
horn to the control rod and fix in to place with a suitable adhesive ensuring that the aileron is not
deflected.
And now the big moment. Attaching the wing.
First thing is to carefully cut away the fuselage under the wing as it will be refitted in place when the
wing is fixed. Support the fuselage (To take loads off the fins) and lower the wing in to the fuselage
recess. Measure from the centre section ends to the fuselage and adjust until both are even and
perpendicular to the fuselage (An asymmetric wing looks bad and flies even worse!!). Mark the wing
lightly as desired to ensure everything is good and make sure all cables etc are not going to get glued
as well, and pass them forwards to the cockpit area. Carefully apply adhesive to the wing seat in the
fuselage and lower the wing in to position making sure the alignment is good all round and hold in
position. Don’t move a muscle until the adhesive has set (p.s. it may not be wise to use 24 hr epoxy
for this). Close the fuselage with the piece cut out earlier and when the adhesive has set run a small
fillet of adhesive all around the wing root.
Undercarriage.
The undercarriage supplied is intended only for static display and stows in the retracted position for
flight. A retract set is available as a seperate module and will have fitting instructions.
The sponsons are made from two depron sides attached to a foam core with UHU-por. Carefully align
the sides over the core before pressing firmly together and repeat for the other sponson.
If fitting static wheels, when cured, the reinforcement for the undercarriage leg mount is glued in
place at the rear of the sponson followed by the leg mount itself. These are clip in mountings so be
careful not to get adhesive in them. Make sure the wheel axis is in the centre of, and perpendicular to
the sponson.
The sponson can now be glued to the wing such that the outside edge of the sponson is in line with the
dihedral break and parallel to the fuselage centreline.
Repeat with the other side.
The wheels are stowed in the retracted position for flight, and these laser cut parts are a cunning and
effective means of achieving this goal. Due to the need for a good fit of parts the builder must
exercise great care to not use too much adhesive.
The first step is to fix the four cross shaped pieces in to the cap strip as shown. When ready glue this
assembly in to the main plate as shown.
This assembly is then glued in to the sponson just in front of the undercariage mounting with the cut
out outboard.
The undercarriage leg should be a snug fit in either location. The mounting for the noseleg is simply
let in to the fuselage so it lies below flush with the fuselage surface.
.
Most of you will not fit U/C due to flying off grass fields, so the suggestion is to make 2 scrap ply
plates per nacelle and fit into the nacelles, with the wheel on a simple wire axel between them. Even
with the fixed U/C up there is enough clearance to have ordinance on the bottom without them getting
knocked off on landing as the wheel, even when reatracted is still half out of the nacelle.
Cockpit/ battery access hatch
At this stage it may be prudent to sand the area around the forward fuselage to the desired profile
before cutting out the hatch.
The length of the canopy on this machine allows for a long hatch underneath which is ideal for
accessing all the equipment. The canopy rests from the noseblock to the start of section 2 of the
fuselage, the way the canopy is designed is that is simply glues onto the fuselage and requires careful
trimming around it to ensure a good fit around the edges and fuselage.
It can be taped/ tacked in place until the hatch is cut. Mark the hatch cut line around the canopy
allowing sufficient material to stabilise the canopy (Approximately 3/8” (9mm) down from the
canopy sides). When satisfied with the marking carefully cut out the hatch with a razor saw or suitable
cutting tool. The locking mechanism is of the builders choice, but a tongue and magnets work very
well in this case. The large canopy begs for detail so now’s the chance. When ready to fit the canopy
secure the canopy/ hatch to the fuselage with suitable adhesive taking care not to deform the hatch
cover.
Fitting the radio gear.
Place the receiver in the desired place and move the battery to achieve the correct c/g. The balance
point is 60mm from the leading edge at the root (this is on the spar) Mark the places where they will
be located. If your fuselage bows in after canopy removal(hysterisis can occure during manufacture
that causes this) make two “U” shaped sections from scrap depron to locate the cross brace and.
ensure that access to the battery area is still possible before gluing in to position. DO NOT GLUE IN
THE CROSS BRACE, FRICTION WILL KEEP IT IN PLACE.
With such a long nose moment there should be little problem arranging the receiver and battery to
achieve the c/g.
The first task is to make suitable trays for the receiver and battery which retain them against launch
and landing loads, plus aerobatics and fix them in place. Bring all the leads to their respective
connecting points and fix connectors or plug in as needed. Ensure easy access is available to the units.
Test allof the controls to ensure that all servos operate in the correct sense with full and free
movement and the motors respond to the commands.
Set up:
Centre of Gravity: 60mm from the leading edge at the root measuring backwards (This would be on
the spar)
Aileron movement: 15mm each way as a good start (adjust to taste after first flight)
Elevator movement: 18mm each way.
Rudder: Maximum achievable
Don’t forget to range check the systems before comitting the machine to flight.
The finishing of the model is left to the builder to choose how much detail is included. The forums at
GAD’s website show what can be done, and offer some good advice and tips on how to get the best
from the materials available.
Extra detail parts are available if the builder wants to create a fully loaded Hog...The sky’s the limit.
Here is an example:
We would like to thank you for purchasing our kit, we hope that it provides you with many happy
hours of ownership and flying.
Also a big thank you to Ady Hayward for making this manual from our deranged meanderings.
The Green Air Designs Team.

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