ARMY TM 9-1240-379-34
MARINE CORPS TM 04332A-34
Section IV. PRE-EMBARKATION INSPECTION OF MATERIEL
IN UNITS ALERTED FOR OVERSEAS MOVEMENT
2-12. GENERAL.
2-14. INSPECTION OF OPTICAL
ELEMENTS.
Pre-embarkation is performed on materiel in
the hands of troops alerted for overseas du-
a. Lenses, reticles, and windows must be
ty to ensure that such materiel will not
free from scratches, pits, dirt, smears, digs,
become unserviceable or worn out in a
fractures, and chips that may interfere with
relatively short time. It prescribes a higher
or affect the optical performance of the tank
percentage of remaining usable life in serv-
periscope.
iceable materiel to meet a specific need
b. Any breakdown or excessive
beyond minimum serviceability.
discoloration of cement between elements of
compound lenses that affects optical per-
2-13. GENERAL INSPECTION.
formance in the field is cause for rejection of
the instrument.
a. Examine tank periscope to ensure that
all component parts are present. Check par-
c. When looking through the tank
ticularly for missing pins, screws, and other
periscope, there must be no evidence of
attaching hardware.
moisture or fungus growth.
b. Check exterior for damaged, cracked,
d. When sighting through the tank
or dented surfaces, bent or broken parts,
periscope, the image and reticle must be
moisture or corrosion, and other evidence of
clearly defined. There must be no indication
misuse that might indicate a need for repair.
of parallax or image tilt as defined in TM
c. Inspect all sealed areas to assure that
9-258.
sealing is still intact.
NOTE
d. Inspect nameplates to ensure that all
Level tank periscope and make
the following checks looking
and easily read.
through elbow assembly/in-
frared body assembly and
e. Inspect diopter scales to ensure that
daylight body assembly.
they are clearly defined and easily read.
(1) Parallax. Look at a target with
f. Inspect for bare spots or damaged
sharp horizontal and vertical lines at a
finish which would expose metal surfaces
distance of 1200 meters (3937 feet);
and lead to corrosion.
parallax must not exceed the thickness of
one reticle line.
g. Test alinement and looseness of body
assemblies by checking periscope latches,
(2) Parallelism. Look at a target with
strikes, plungers, and brackets.
sharp horizontal and vertical lines at a
distance of 1200 meters (3937 feet). The
h. Check that deflection and elevation
lines on the target should be parallel with
boresight knob assemblies are firmly seated
the lines on the reticle image within 2 mils
against clutches.
of arc.
i. After recording setting of each
NOTE
boresight knob assembly, disengage knob
This is with Periscope installed
from clutch and rotate it through its com-
in tank and inspected at the
plete range. Operation must be smooth
time of synchronization and
throughout. When finished, reset knob to
alinement.
position recorded before disengaging.
