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 285 of 775

TM 9--2350--311--10

Change 6

2--187

2--12 PREPARATION FOR FIRING — CONTINUED

2--12.2

Boresighting — Continued

f.

Comparison Test of the M140/M140A1 Alinement Device — Continued

2

Install a second M140/M140A1 alinement device (27). If using ERLS version, depress button (36.1) to

activate. Without moving position of M117/M117A2 panoramic telescope (18), view through eyepiece

(37). If M117/M117A2 panoramic telescope reticle and M140/M140A1 alinement device reticle aline, you

have verified accuracy of M140/M140A1 alinement device.

3

If M117/M117A2 panoramic telescope (18) reticle and second M140/M140A1 alinement device (27)

reticle do not aline, or if azimuth counter (19) reading is not correct after reticles are alined, one of two

M140/M140A1 alinement devices is unserviceable.