A PORTABLE RECHARGER HOSE is available at every station in the ship.
Every crew member should know their location so well that they can be
located immediately, even on the darkest night. In addition, there is a
long recharger hose for filling the ball turret oxygen cylinder.
(B-17-F).
When drawing oxygen through a portable recharger the refiller valve
must engage the filler nozzle TIGHTLY, otherwise oxygen leaks around the
connection and is lost. The oxygen supply of an entire system has been
wasted in this manner.
FREEZING or STICKING of refiller valve is not uncommon at extremely
low temperatures. Always check this after refilling your walk-around. A
stuck valve will quickly deplete the entire supply of oxygen in that
system. If the valve is stuck plug in a walk-around bottle and leave it
there.
USES OF THE WALK-AROUND BOTTLE -- (1) As an ACCESSORY REGULATOR --
the A-13 regulator on the walk-around bottle is a demand type regulator
without the "auto-mix" feature. It gives 100% oxygen on inspiration
regardless of the altitude. By connecting the walk-around bottle FIRMLY
into the portable recharger valve, one has an extra source of oxygen at
that particular station. As long as the oxygen gauge at the station
registers oxygen pressure the user is assured a supply of pure oxygen
... his supply is coming directly from the system. Remember this when
reviving a passed out crew mate in the waist in the vicinity of the ball
turret--the long recharger hose used to charge the oxygen bottle on the
ball turret can be plugged directly into a walk-around bottle attached
to the unconscious crew member's mask.
If other long recharger hoses can be obtained from Tech Supply they
will be extremely handy attached at the pilots station, in the bomb bay
and to the recharger outlet at the right waist gunner's station. This
would permit the engineer, who in flight is continuously filling his
walk-around bottle, considerable liberty. He could cover most of the
ship, staked out on a long recharger hose connected to his walk-around
bottle. It would also provide a readily accessible source of oxygen to
revive crew members who pick such out-of-the-way places to pass out as:
the bomb bay cat-walk, the bomb bay doors, under the flight deck, or in
some remote part of the waist.
One or two extension portable recharger hoses shown in photograph
page 22 should be standard equipment in heavy bombers.
[Illustration: Fig. 5 EXTENSION RECHARGER HOSE]
(2) SOURCE OF OXYGEN FOR BAIL-OUT -- Above 20,000 feet, breathing of
oxygen is necessary to reach your particular escape hatch. After this
spot is gained you won't need oxygen ... unless you start fiddling with
the rip-cord too soon. Go to your exit on the walk-around bottle, fill
your lungs deeply five or six times from the bottle, HOLD YOUR BREATH,
and take the dive. Continue to hold your breath during the descent as
long as possible. By the time your lungs are bursting for air you'll be
from 8 to 10,000 feet nearer the ground and won't need extra oxygen.
Leave the mask on--it will protect your face. If the skies are filled
with enemy planes it may be wise to continue the free fall. By now you
can start breathing without danger of serious oxygen-lack. Any dimming
of mental acuity would be of such short duration that you'd have plenty
of time to pull the ripcord.
PRACTICE GOING TO YOUR ESCAPE HATCH ON A WALK-AROUND BOTTLE DURING
OPERATIONAL TRAINING -- PRACTICE ON JUST HOW YOU WOULD CLEAR THE SHIP --
GO THROUGH ALL OF THE ROUTINE EXCEPT THE BAILOUT and that might not be
time wasted, at least just once before the time comes when you might
have to!
Above 30,000 feet you wouldn't want to open your 'chute even if you
had plenty of oxygen. You'd freeze a hand or foot or both if you did.
Under these conditions you'd free fall, holding your breath, as long as
possible. Then, after three or four breaths of "thin" air, pull the rip
cord. Your altitude should be in the vicinity of 10,000 to 12,000 feet
below that when you abandoned ship, and the degree of oxygen-lack
encountered here wouldn't be of dangerous consequence. You'll avoid
freezing, and perhaps the gunfire of enemy interceptors.
(3) TO MOVE ABOUT THE SHIP For this the walk-around bottle is very
useful ... and very tricky! The trouble is that the thing is good only
as long as it gives oxygen. It will rarely, if ever, be fully charged so
forget that 8 to 12 minute stuff. You can't fill your bottle any fuller
than the pressure in the line you'll be drawing from. And the only time
that will be fully charged is when the ship is on the ground, freshly
charged with oxygen, ready for the take-off. When you need the
walk-around bottle, three or four hours will have passed ... and the
pressure in your filling line will be some fraction of the full charge.
As a rule you'll do well to get the bottle half charged. And you're
going to be moving about at altitude and needing 3 to 5 times as much
oxygen as if you were sitting quietly in a corner. So plan on the
walk-around supply lasting 1½ to 2 minutes ... then you won't be caught
short Refill the bottle frequently. Refill it every time you pass a
portable recharger hose ... and there's one at every station. Failure
to do this has caused more pass-outs in second and third phase training
than any other single cause ... unless you include carelessness. And
careless people don't last long in the kind of work you're specializing
in! There's a check-valve on the walk-around bottle, so you won't lose
anything if you plug into a system that reads less than the gauge on the
bottle.
NOTE TO ENGINEERS: Because of its limited supply, the standard
walk-around bottle is next to useless for many of your jobs which must
be done in flight on a walk-around bottle. The ENGINEER NEEDS A LARGER
WALK-AROUND BOTTLE. One, having a supply 5 TIMES AS GREAT as the
standard portable cylinder, can be obtained as follows:
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).
[Illustration: 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.