4. Open valve (E) slowly to maintain a
pressure of 10.0 inches H2O throughout the
system as indicated on manometer (4). Close valve
(E). Any further climb on manometer (4) indicates
a leak through valve (H).
5. Open valve (E) to maintain 20.0 in. H2O.
When pressure is constant, observe rotameter (8).
There should be no leakage.
6. Turn valve (F) to LOW RANGE. The
rotameter (7) should indicate no leakage.
7. Return valve (F) to HIGH RANGE, and
close valve (E). Remove the hose from connec-
tion (19) and allow the pressure to escape from
NOTE: Open valve (C) to aid in relieving
pressure; then close it.
8. When the pressure has equalized, connect
the hose from tap (21 ) to tap (20) in the chamber.
Rotameter (6) should show no indication of
9. Remove the cap from Piezometer (26),
and disconnect the hose between taps (20) and (21)
in the chamber.
10. Turn the regulator (N) counterclockwise,
and open valve (S) to bleed system. Close all test
stand valves with the exception of valves (R) and
Altitude Chamber and Suit Simulator
Tank Inward Leakage Test
Perform the altitude chamber and suit
simulator tank inward leakage test as follows:
1. Place valve (D) in the Hg position. Ensure
the ON/OFF valves (G) and (L) are in the OFF
position. Place valve (0) in the suit simulator
2. Close the chamber door and turn the
vacuum pump motor ON.
3. Open the VACUUM CONTROL valve
(B1) and ascend to 30,000 feet. Close (B1) and
check to ensure that the same altitude is indicated
on both altimeters (12) and (13). At 30,000 feet
you will see the high-range altimeter start to climb
and at 40,000 feet the low-range altimeter will no
longer be in use. This happens automatically and
the low-range altimeter will not be damaged.
4. Using valve (B1) ascend to 40,000 feet;
ensure that altimeters (12) and (13) register the
5. Using the VACUUM CONTROL valve
(B1), ascend to 52,000 feet. (Altitude is indicated
on altimeter (12).)
6. Close (B1); after a 2-minute stabilization
period, record the altitude indicated on altimeter
(12). Altitude loss should not exceed 1000 feet
in 20 minutes.
Periodic inspections consist of daily, weekly,
biweekly, and monthly inspections. Perform these
inspections at the prescribed intervals using the
procedures described in the following text.
Perform the daily inspection as follows:
1. Check the vacuum pump lubricant for the
proper level (run the pump for 2 minutes and
recheck for proper level).
2. Inspect the gauges and manometers for
cleanliness, fogged or broken glass, and zero or
3. Inspect the altitude chamber door for
cleanliness, chips, scratches or cracks. Check the
gaskets for excessive wear or deterioration.
4. Inspect the connections and adapters for
cleanliness and distortion.
5. Check the identification plates for
cleanliness, legibility, and security of attachments.
The weekly inspection includes all the tasks
of the daily inspection and the following addi-
1. Inspect the polyethylene tubing, fittings,
connections, and rubber couplings for the correct
fit, dirt or excessive dust, pin holes, radical bends
or kinks, surface abrasions and heat blisters.
2. Inspect the gauges, manometers, and
flowmeters for the correct calibration decals,
proper fluid level, and cleanliness of manometer
and flowmeter tubes.
3. Perform the pressure leakage tests in
accordance with NAVAIR 13-1-6.4.