TM-9-2350-311-10

HOWITZER, MEDIUM, SELF-PROPELLED, 155MM; M109A2, M109A3, M109A4 AND M109A5

TECHNICAL MANUAL; OPERATOR’S MANUAL

NOVEMBER 1994

TM-9-2350-311-10 - Page 500 of 775

TM 9-2350-311-10

3-7 FIRE CONTROL ALINEMENT TESTS AND MEASUREMENTS — CONTINUED

3-7.5

Leveling the Cannon Tube — Continued

a. Leveling the Cannon Tube Using the Cannon Tube Leveling Fixture (If Required) — Continued

8 Elevate or depress the cannon tube (2) until the M1A1 gunner’s quadrant (13) bubble (16) is centered.

9 Reverse the M1A1 gunner’s quadrant (13). The bubble (16) should center again.

10 Check to see if M15 elevation quadrant (1) elevation bubble (3) is still centered. If adjustment to center

elevation bubble is more than ± 0.5 mil, notify unit maintenance.

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