TM 55-4920-403-20&P
C H A P T E R 3
A V I A T I O N U N I T M A I N T E N A N C E I N S T R U C T I O N S
Section I. GENERAL
3-1. Descriptive Information.
e. Information on care, repair and parts for
a. Refer to TB 43-0124 for aviation unit mainte-
the environmental control unit can be ‘found in
nance to be performed on the shelter.
TM 5-4120-239-14.
b. Maintenance of grinding machine can be
f. Power cables may be field repaired using a
found in the appropriate technical manuals and
standard blade screwdriver to replace connector. Refer
manufacturer’s literature.
to drawing 4920-EG-058 (figure D-4).
c. Replace unserviceable components of shop set.
g. Have an aircraft electrician or other qualified
person work on electrical parts of the shelter.
d. Refer to the maintenance allocation chart
(Appendix B) for aviation unit maintenance to be
performed on the shop set.
Section Il. MAINTENANCE INSTRUCTIONS
3-2. Shelter Maintenance. Inspect shelter care-
fully for defects. Refer to TB 43-0124 and TM 11-
5410-213-14P for repair procedures and replace-
ment parts.
3-3. Fixture Maintenance.
a. Work Table. The worktable is part of the tool set
and replacements may be ordered from the Supply
Catalog. Remove and save the mounting bolts, lag
screws and brackets (items 10, 17 and 25, figure D-1)
from the original work table. Place the new worktable
on the floor mounting plates (item 26, figure D-1) and
install bolts. Bolt angle brackets (item 10, figure D-1) to
wall; then, using the bottom hole as a guide, drill the
table top and install lag screws.
b. ECU Shipping Bracket. If the ECU shipping
bracket or its straps are found to be unserviceable,
remove the four bolts and Iockwashers securing it to
the floor, replace with a new bracket and reinstall the
bolts and Iockwashers.
c. ECU Shelf Assembly.
(1) The ECU support cable assembly (item 12,
figure D-2) may be replaced by drilling out the two blind
rivets (item 85, figure D-2), removing the two screws
(item 88, figure D-2) and removing the hook (item 101,
figure D-2) from the “D” ring on the shelter. Position
the new cable assembly and install the appropriate
hardware. Be sure to crimp the hook over the “D’’ ring
to secure it.
(2) The ECU support shelf itself may be
replaced by removing the “D” ring as previously
explained and removing three screws (item 96,
figure D-2). Reverse this procedure to install a new
shelf support.
(3) The hinge (item 69, figure D-2) may be
replaced by removing three screws (item 96, figure D-2)
and drilling out 13 rivets (item 97, figure D-2). Rivet
the replacement hinge to the shelter and reinstall
three screws.
d. Compressed Air Panel.
(1) The plug assembly (item 9, figure D-2)
may be replaced by drilling the rivet (item 84,
Change 3 3-1
