Rigging The Rudder And Elevator Control Wires; Installing And Rigging The Upper Wing Center Section And Struts - Model Airways CURTISS JN-4D JENNY Instruction Manual

Installing the horizontal stabilizer (Figure
Set the horizontal stabilizer, which
7-3):
already has the vertical stabilizer and elevators
attached, to top of the fuselage at the tail. Block
up each end of the horizontal stabilizer so it's
an equal distance above the building board on
each side. Glue the horizontal stabilizer to the
top longerons of the fuselage. On the real air-
craft, the stabilizer is bolted with U bolts to the
fuselage, which can be faked using brass wire.
These fasteners go through the blocks and pads
you already have on the horizontal stabilizer.
Or, you could omit the U bolts altogether.
Below the horizontal stabilizer there are two
wooden struts on each side from the stabiliz-
er to the fuselage. Add these now. You should
have already made these when you built the
stabilizer. Sheet 4 illustrates all the mount-
ing details for the tail surfaces.
The brace wires from the horizontal to verti-
cal stabilizer were added when you assem-
bled these, so no further rigging is required
(unless you forgot, of course).
Installing the rudder (Figure 7-4):
rudder, which has already been fitted with
the control horns, can now be installed. The
fake hinges (brass strip) fit into slots cut into
the vertical stabilizer, the fuselage tailpost,
and the rudder leading edge.
3. Rigging the Rudder and
Elevator Control Wires
See . Now that the stabilizers, rudder
Figure 7-5
and elevator are installed, rig the control wires
for these (gray nylon cord on the model). The
rudder has two control horn back brace wires,
from the control horn to the fittings on the
trailing edge of the rudder on both sides. Turn-
buckles (R3A short) are located at the rudder
trailing edge. On the real aircraft, the wires are
fitted to a shackle on the control horn. For this
model, just tie off the wires at the horn.
The wires forward of the control horns go
directly to the rudder bar in the after cockpit.
If you did not install these when you installed
the rudder bars, do so now. A connecting wire
is between the forward and after cockpit rud-
der bars. Fit turnbuckles (R3A short) just
behind each rudder bar. Refer back to the rud-
der bar installation, Stage 4,
Figure 4-3
Three back brace wires (top and bottom) for
each of the elevator halves are fitted in a sim-
ilar manner. The turnbuckles (R3A short),
like the rudder, are at the trailing edge. The
forward wires go directly to the elevator
beams in the fuselage. For these wires, locate
the turnbuckles (R3A short) at the beam end
of the wires if you have not done so. Refer
back to Stage 4, relating to the
Figure 4-5
elevator bar assembly.
On the real aircraft, as the control
Note:
wires pass through the fuselage there is a
leather or fiber fairlead stitched into the cov-
ering fabric of the fuselage. However, since
the model is uncovered, these fairings are
not present. Nevertheless, make sure both
the rudder and elevator control wires have a
clear run from the cockpit to the rudder and
elevator without hitting any structure.
FIG. 7-3 INSTALLING HORIZONTAL STABILIZER
SPAR
U BOLTS
AROUND
LEADING
LONGERONS –
EDGE
OR OMIT
HORIZONTAL
STABILIZER
The
SLOTS IN VERTICAL STABILIZER
FIG. 7-5 RUDDER & ELEVATOR CONTROL WIRES
AFT RUDDER BAR
IN FUSELAGE
.
LEFT ELEVATOR BAR
IN FUSELAGE
(RIGHT SIDE SIMILAR)
4. Installing and Rigging the Upper
Wing Center Section and Struts
The basic struts have already been assembled
when you constructed the wings. Insert the
four center section struts into the holes
through the W22 fittings, in the underside of
the wing center section. Check the side angles
of the struts and bend to correct position if nec-
TRAILING EDGE
EYE BOLT (BOTH SIDES)
BOLT (WIRE) THROUGH EYES
AND TAILPOST – OR OMIT
BRACE WIRES
VERTICAL
STABILIZER
GLUE TO
WOOD
LONGERONS
STRUTS
JIG BLOCK
FIG. 7-4 INSTALLING THE RUDDER
FAKE HINGES –
BRASS STRIP
SLOTS IN TAILPOST
CONTROL LINES –
.010" NYLON GRAY CORD
CONTROL HORNS
34
PIN
STRUTS PREPARED EARLIER
R1
EQUAL
BOTH SIDES
WORK SURFACE
RUDDER
SLOTS IN
RUDDER
TURNBUCKLES
R3A – SHORT
BACK BRACE WIRES
(SAME BOTH SIDES)
BACK BRACE WIRES
(SAME ON BOTTOM
AND RIGHT SIDE)
essary. Looking forward or aft, the struts are
perfectly vertical. When the struts are aligned,
glue in place with super glue. Set the assembly
on top of the longerons, inside the upper clip
fittings (F20) formed as a socket at Stations 4
and 5. Check the alignment of the center sec-
tion and when level, glue the struts to the
longerons and the clip fittings
The center section unit is not very strong at
R1 AT
TAILPOST
.
(Figure 7-6)