(12) After final adjustment:
(a) Close the pressure-tank valve.
(b) Open the fuel valve and release the pressure from the fuel tanks.
(c) Remove the pressure gage and plug from the fuel tank.
(d) Install filling plug.
(e) Tighten filling plug with wrench.
(f) If regulator is spring-type, replace its protective cap.
68. FUEL-TANK ASSEMBLY.
a. Description and functioning. (Figs [4], [5], and [39]) The fuel-tank assembly includes:
(1) Fuel tanks. Two alloy steel fuel tanks hold the fuel before it is propelled to the target. They have a combined capacity, including void, of 4-1/2 gallons. A void of approximately 1/2 gallon is left in tanks when filling to allow for expansion and to permit entry of the compressed nitrogen or air. To speed filling and cleaning of the tanks, two openings are provided on top of the fuel tanks. The openings are threaded to receive the filling-plug assembly and the safety-head plug assembly, which are interchangeable in the openings. Filling operations involve the use of auxiliary equipment and are described in Paragraphs [34] through [40]. The carrier and the pressure system are supported on the fuel tanks.