TM-9-2350-311-10 M109 Operator's Manual for M109A2, M109A3, M109A4 and M109A5 Download

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TM 9-2350-311-10 1-14 EQUIPMENT OPERATION AND DESCRIPTION - CONTINUED 1-14.12 NBC System (M109A4/M109A5 Only) a. b. c. d. NBC CONTROL BOX ASSEMBLY. The NBC control box assembly (1) located at commander’s station turns the NBC system on and off. M2A2 AIR PURIFIER. The M2A2 air purifier (2) pulls contaminated air through gas and particulate filters and distributes clean air through hoses to individual M3 electrical air heaters. M3 ELECTRICAL AIR HEATERS. The section chief’s heater (3), cannoneer no.1’s heater (4), gunner’s heater (5), and assistant gunner’s heater (6) located on the cab ceiling and cannoneer no. 2’s heater (7) and driver’s heater (8) located in the hull warm filtered air for individual comfort. ORIFICE CONNECTORS. The orifice connectors (9) attach purification system to M25A1 field protective masks. 1-40