User Manual

16
Required Parts
• Wing panel (right and left) • Mechanical retract (2)
• 6" servo extension • 4-40 nut (2)
• 4-40 metal clevis (2) • Ball end (2)
•#2 standoff (2) • 2-56 nut (2)
• Clevis keeper (2) •#2 washer (2)
• Retract doors (right and left)
• 4-40 x 1/2" threaded rod (2)
• 2-56 x 3/8" socket head screw (2)
• 4-40 x 1/2" socket head screw (12)
• Retract servo with hardware (2) (JRPS791)
• Connector back plate (2)
• 1/2" aluminum servo arm (2)
• 4-40 x 3/8" socket head screw (2)
• 6-32 x 1/2" socket head screw (8)
•#2 x 1/2" sheet metal screw (4)
Required Tools and Adhesives
• Threadlocking compound • Felt-tipped pen
• Drill • Drill bit: 1/8"
• Phillips screwdriver • 3/32" hex wrench
• 4-40 tap
Note: The P-51D retract system is designed
to use low profile hi-torque retract servos,
such as the JRPS791. All adjustments to the
retracts are made before the final installation.
  Step 1
Position the retract mechanism over the wing to determine
on which side to mount the retract servo. Use a 4-40 tap
to make the appropriate holes in the mounting plate if
necessary.
  Step 2
Attach a 6" servo extension to the retract servo and
secure the extansion to the servo lead so it won’t unplug
accidentally.
  Step 3
Mount the retract servo to the mounting plate using
four 4-40 socket head screws. It may be necessary to
install the spacer plates depending on the servo
selected. Use threadlock on the screws to prevent them
from vibrating loose.
  Step 4
Attach the servo horn to the retract servo. It is
positioned so the arm moves from one end of the
mechanism to the other.
Section 3: Retract Installation