Fuselage Assembly - Mitsubishi Ki-15 Babs Construction Manual

Overview of the fuselage assembly:
A horizontal crutch framework of ¼" sq. balsa is assembled over the plans on a flat
surface. First, the upper half of the fuselage is attached to this crutch. Then the cockpit interior is
painted and installed before sheeting. The glassed and primed vertical stabilizer is installed;
sheeting of the fuselage is completed and sanded. Then the fuselage is turned over; and the
lower halves of the fuselage formers, tank box and wing saddle are installed. Finally, the bottom
half is sheeted and wing filets are added.
Midway thru this process, before the lower nose and wing filet are completed, the wing is
mated to the fuselage. See notes in Wing Construction.
A removable horizontal stabilizer is shown. This provides access to the rudder and
elevator servos and it allows the airplane to be carried in a compact car. It also makes the
fuselage and stab easier to work on. If you prefer, the stab can just be glued in place.
The cowl assembly instructions are shown separately in another section.
Let's begin.
The fuel tank is enclosed in a plywood box. The front of the box is a removable firewall.
The firewall is screwed to hardwood blocks inside the tank box which are, in turn, screwed and glued to
the inside of the tank box. A total of eight flat-head aluminum screws are required for the firewall plus
another eight for the blocks. To adapt to engines other than those shown on the plans, the tank box can be
shifted forward or rearward as needed. Line the box with soft foam rubber for a snug fit of the tank. Slip
string or tape around the tank before installation. The string or tape can be used to pull the tank out later
as needed for maintenance. The rear and side seams of the tank box should be completely sealed with
glue so that if the tank leaks, fuel will spill out the front of the tank box and onto the ground, not into the
interior of the fuselage (you don't want that to happen).
Fit the engine to the firewall with blind nuts at this time. Remove the engine.
Drill two holes in the firewall for the vent and fill lines. Install the tank and fuel lines and attach the
firewall to the tank box.

Fuselage Assembly

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