Obtain a D-2 oxygen cylinder (stock No. 5500-344020 - class 03K) from Air Corps Supply. Remove the A-13 regulator assembly from a standard walk-around bottle. Remove the spud from one end of the D-2 cylinder and screw the A-13 regulator in tightly. Fill to 400 p.s.i. and leave overnight to determine if pressure is maintained or lost due to a leak. (A drop of 25 to 50 pounds will occur in the absence of a leak due to cooling of the oxygen which warmed up when the cylinder was charged).

Fig. 6
D-2 WALK-AROUND BOTTLE

For leaks here or elsewhere in an oxygen system use the following anti-sieze and sealing compound on the pipe threads: Pioneer Antisieze No. 2., Class 96B, Stock no. 7500-050800. Never use a sealing compound which contains oil.

A satisfactory bag with shoulder strap for carrying the walk-around bottle when in use can be made from heavy twill or canvas by the parachute department.

EMERGENCY OXYGEN EQUIPMENT

In addition to your ship's regular oxygen supply, you will take emergency oxygen rations along on combat missions. If practical you will also have several extra masks on board. Know where they are stored.

  1. Both of the low pressure walk-around bottles should be kept as full as possible-- you never know when you may need them. If full, the small walk-around bottle is good for only a few minutes, the large for 30 to 45 minutes, depending on your activity.
  2. High pressure equipment.
    1. A-2 bottle with bag-mask. (Fig. 7)
    2. In some theaters each combat crewman is issued this equipment. The high pressure bottle is fully charged to 1800 and will last approximately 45 minutes to one hour. It is used with the continuous flow mask.
    3. Fig. 7
      A-2 OXYGEN BOTTLE WITH BAG MASK
    4. Bail-out bottle. (Fig. 8)
    5. This small high pressure cylinder is a "last resort" source of emergency oxygen. It contains approximately 12 minutes supply. The old style bottle (H-1) is equipped with a pipe stem which is held between the teeth. A newer bail-out bottle (H-2) has a bayonet connection so it can be used with an A-14 mask with bail-out adapter (see fig. 8).
    6. Fig. 8
      BAIL OUT BOTTLES

PRESSURE GAGE

Your oxygen pressure gage registers from 450 pounds to zero. WATCH YOUR PRESSURE GAGE! Except under extreme emergency, don't run the pressure down under 50 pounds .... if you do there's danger of moisture getting into your refiller line. Then the next time you go to high altitude you'll have trouble with freezing in the oxygen line.