Assembly Instructions
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Rights and lefts are determined while standing at the tail and looking towards the nose of the airplane.

Bolts and clevis pins should be installed with heads up, forward or outboard.  Make it a practice to tighten the nut and insert the cotter key on each bolt as used, never leaving any finishing process to be done at a later date.  This will avoid the possibility of leaving out the very important cotter keys.

Wing Rigging

Attach the interplane struts to the upper wings using a 3/8" x 2 1/2" bolt at the front spar and a 3/8" x 2 1/8" bolt at the rear spars.

With one man at the tip and two men at the root of the lower wing, attach to the fuselage using a 7/16" x 3 1/8" bolt at the front fitting and a 1/2" x 2 3/4" bolt at the rear fitting.  Place padded support under strut point for temporary support of wing.

With two men at the tip and three men at the root of the upper wing, attach to the fuselage using a 7/16" x 2 3/4" bolt at the front fitting and a 1/2" x 3 1/4" bolt at the rear fitting.

Attach the lower ends of the interplane struts to the lower wings using a 3/8" x 2 3/8" bolt at both the front and rear fittings.  Then attach the main wing brace strut using a 7/16" x 2 5/8" bolt at the upper end and a 7/16" x 2 1/2" bolt at the lower end.  Adjust the connection at the upper rear interplane strut so that the upper wings are rigged flat and also the lower, by means of adjustment at the lower rear point of the interplane strut.  By rigging the wings flat we mean that the lower support of each wing should appear entirely flat, not warped up or down, when viewed from standing at the wing ends.  This can best be observed on the lower wings by standing ahead of the wings in a position where you can sight the lower surface of the wings.  If properly rigged, the airplane should fly in a normal course with "hands off" for indefinite period in smooth air.  However, if it should prove to be a little right wing heavy, for instance, this can be corrected by shortening slightly the right upper interplane strut adjustment, or if the left wing is heavy, the same procedure on the left interplane strut should be followed.

With the control wheel in a neutral position, assemble the aileron control cable ends protruding from each side of the fuselage to the cables located in the upper wings.  This can be accomplished through the wing inspection holes provided for same, using the bolts which are left assembled in the cable ends.

Adjust the cable so the trailing edge of the ailerons will e parallel to the trailing edges of their respective wings.  Lubricate the various working parts of the control system according to the attached diagram.  Attention is drawn to the fact that controls will naturally be rather stiff on a brand new airplane until they have been somewhat worked in.

Next, connect all wiring leading from the wings to the fuselage, using the Jones plugs provided for same which are located in wing and fuselage over front window under detachable upholstery panel.

Tail Assembly

Assemble stabilizer and elevators to fuselage by attaching stabilizer at rear connection with to 5/16" x 1 3/8" bolts making sure the stabilizer brace rod which runs from the center of the front stabilizer spar to the rear spar is connected under the head of the right hand side and left side bolt.  Also, the stabilizer should be assembled so that the fitting which attaches to the adjustment screw is on the lower side of the stabilizer.  With the stabilizer in down position, attach the stabilizer indicator cord to front spar so that indicator in cabin ceiling registers down or full back.

With the control column in a neutral position connect the elevator cables to elevator horn and adjust so that elevators are in a neutral position.  When properly adjusted the leading edge of the elevator at the extreme point of balance should have a down travel below the stabilizer leading edge when it full down position, of approximately 7 1/2".

Install fin in place by sliding rear fitting into tail post socket and front fitting over bushing provided for same in stabilizer guide post, using three 1/4" x 1 1/4" bolts at the rear and one 5/16" x 2 1/4" bolt at the front.

Next, install rudder to find inserting bearing "U" bolts in pad provided for same.  With the rudder pedals in a neutral position, connect control cable shackles to rudder horn and adjust the turnbuckles through the belly access opening until the rudder is straight with line of flight.

Next, splice tail light wires inside of fuselage taking care to tape the connections so that the possibility of short circuit is eliminated.  Attach top and bottom tail wires to fittings provided for same and tighten so that the two top wires will be the same length and the two bottom wires will be the same length, the short pair of wires being the lower and the long pair the upper.  Then attach tail cowl to fuselage using the screws and brackets provided for same.

Gas Tank Fittings

Screw vent lines in place in upper surface of upper wings taking care to have openings in gooseneck line towards the REAR.  Do not use any "Gastite" solution on threads at this joint.


Make sure propeller hub and propeller shaft are perfectly clean.  Cover the propeller shaft with Mobiloil Aero "H".  Force the propeller on the shaft tight using the small nut which screws on the end of the shaft.  Screw the lock nut on the propeller and lock it with the wire provided.

Oleo Shock Strut

These shock struts are so constructed that initial landing shock is absorbed by the oleo action before the piston reaches the shock spring at the top of the strut.  Taxi shocks are absorbed by this coil spring in combination with the normal oleo action of the strut.

You will note there is practically no rebound after the initial impact with the ground in a landing, as this initial impact is taken entirely by the oleo action of the strut.

Very little maintenance is required.  It only being necessary to check the oil level occasionally, every 100 hours if the ship is in regular service.

We suggest that at the end of each 200 hours you dismantle this strut completely, cleaning each part with gasoline, inspecting and refilling with new oil.

Instructions for Filling Strut

1.  Remove lock wire locking 1/8" pipe plug at upper end of shock strut and remove plug, which in turn has the oil level gauge attached to it.

2.  If necessary, add enough oil to appear in the region of the perforated portion of gauge strip.  Replace plug securely being sure to lock in place with lock wire.

3.  General Electric #6 Transformer oil, electric refrigerator compressor lubricating oil, or Lockheed Brake fluid must be used.  If neither of these are available, a half and half solution of castor oil and alcohol may be used.

Instructions for Dismantling and Assembling Shock Strut

(Illustration #1) (Part #35013)

To disassemble this strut the procedure should be as outlined below.

1.  Remove lock wire ring, #14133 shown on assembly drawing, holding nut #14132 at top end of shock strut.

2.  Remove cap screws shown in section A-A holding splined fitting #35013 in place.

3.  Remove the two 1/4" x 3/4" hex bolts holding flange #35024 in place at the bottom end of outer cylinder.

4.  The above three operations having been accomplished, all the internal parts of the shock strut can be removed by pulling on sliding member from the bottom end of the outer cylinder.

5.  Remove bolt and taper bushings shown in Section B-B on assembly drawing, which in turn will enable axle socket to be removed from sliding member.

6.  Remove #10-32 set screw in end of sliding member and remove needle assembly #35030 using special wrench provided for same.  This is done by turning wrench anti-clockwise.  To prevent spilling of oil care must be taken to stand shock strut in a vertical position with the sliding member end at the top.

7.  By the removal of this part, it is now possible to drain all the oil into a container.

8.  Having removed needle assembly it is now possible to withdraw piston assembly #20479 from end of sliding member.

9.  Remove 1/8" pipe plug in top of piston assembly and flush out inside with gasoline.

10.  Before spline shaft is reassembled pat on a generous quantity of good clean cup grease in the splines and around the lower bearing, also around the large spring.  To assemble strut reverse all operations except that the 1/8" pipe plug should not be inserted until the strut assembly is in place on the ship and ready for filling.

Gasoline System

Your WACO airplane is equipped with what is considered the simplest, most practical gasoline system obtainable, namely a direct gravity flow of gasoline from wing tanks to carburetor.  However, owing to the comparatively thin wing section, it is necessary that these tanks be fairly long and shallow.

These tanks will drain to almost the last cup of gasoline in normal flight position but it is important that you have at least ten gallons of gasoline in the thank used for the take-off before a take-off is attempted.  This will insure a steady and continual flow of gasoline to the carburetor.

Another item to take into consideration is that on the ground the gasoline will collect at the lower end of the tank, and since the gauges are located pretty well in the center of the tank, an accurate reading cannot be obtained from the gasoline gauge on the ground, although these gauges are quite accurate for use in level flight.  Therefore, particular care should be taken in checking the gasoline supply while the ship is on the ground.

It is important that vent lines protruding from top tanks be kept open at all times.  It is also important that gas tank caps fit snugly and do not leak.  Occasionally, the steel clip fittings which hold these tank caps in place will get pulled out of shape and not have the correct tension.  This can be quickly remedied by putting them back in shape with a pair of pliers and if this fails to stop the leak, one or two new cork gaskets should be used on the caps which will stop the leak.

You need not become alarmed if, after filling the tanks completely, one tank appears to drain faster than the other.  This is normal and there is no set rule as to which tank will drain the fastest under certain conditions.  On some airplanes, one tank will one day and the other the next.

You will note the tanks have been provided with two outlet lines, one at the front and one at the rear.  This is to take care of all conditions and make sure the carburetor gets gas both during a steep climb and a steep descent.

If the tanks appear to leak, first make sure that all fittings are tight before going to the trouble of removing the tank.  Leaks are usually found to be around the fittings and are easily repaired by tightening, or, if necessary, removing and adding filler, such as clear dope or white lead to the threads and replacing.

Care of the Fire Extinguisher

Be sure that the extinguisher is kept full of liquid (up to the level of the filler plug hole) and once every thirty days the extinguisher should be removed from the bracket, the handle unlocked and given a couple of pumps, after which the handle should be properly locked.  Then with a downward movement (as used in making the ink in a fountain pen flow) clean the fluid out of the discharge nozzle.

By following these suggestions and the information printed on the label on the extinguisher, you have an extinguisher that will function properly at the time you need it, and further prolong the life of the extinguisher.

Care of the Airplane

Your WACO airplane is a piece of fine machinery and is deserving of care and attention.  When not in use it should be stored in a hangar as near dustproof, weatherproof and fireproof as is available.  The finish of an airplane deteriorates much faster when left out in the weather than when properly sheltered.

Cleaning the Airplane

It is desirable to keep the airplane clean both inside and outside at all times.

We advise the use of gasoline for cleaning the airplane finish only when it is absolutely necessary to remove grease spots.

The best method of cleaning the airplane is to use warm water and a flake soap, washing a spot of say three square feet at a time and rinsing immediately afterward.  Begin at the upper surface of one of the top wings and wash that wing, both upper and lower surface, working in from the tip end and across to the other side.  Then wash fuselage, tail surfaces and lower wings and last landing gear.

After completely washing and rinsing one surface, say one complete wing, if a chamois is available, go over the surface with the chamois which will add to the smoothness and lustre of the finish.

While washing the airplane, one has a good opportunity to inspect the vent patches along the lower side of the trailing edge of the wings and tail surfaces.  These patches should be kept open at all times and it is well to make sure these are open by sticking a small instrument, say a match or something of that nature, through the holes as you come to them while washing.  Care should be taken to keep water off the motor and also out of the cabin. For ships upholstered in leather we recommend a good grade of saddle soap be used to keep the leather clean and pliable.

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