TM 55-1510-222-MTF
11. Cabin pressurization switch - PRESS.
12. Cabin pressurization controller - Set to 0 feet.
13. Continue climbing to between 15,000 and 16,
000 feet. As the cabin descends to 0 feet. insure
that the ALT WARN annunciator extinguishes
prior to 9,000 feet cabin altitude.
14. Cabin rate of climb knob - Set to minimum.
Monitor the cabin rate of climb for a rate of less
than 200 feet per minute.
15. Cabin rate of climb knob - Set 1 to 3 o’clock po-
sition. Monitor the cabin rate of climb for a rate
of 350 to 650 feet per minute.
16. Cabin rate of climb knob - Set to maximum.
Monitor the cabin rate of climb for a rate of
1500 to 2500 feet per minute.
17. Cabin altimeter - Check that the cabin altimeter
needle stabilizes and remains at -250 to + 250
feet until the maximum differential pressure of
6.5 ± .1 PSI is reached. At this point (approxi-
mately 15,300 feet pressure altitude), cabin alti-
tude should increase and differential pressure
should remain constant.
18. With the cabin at maximum differential pres-
sure. place both bleed air valve switches to EN-
VIR OFF. As the cabin diffential pressure de-
creases from approximately 6.1 to 5.7 PSI, the
cabin rate of climb shall not exceed 2200 feet
per minute.
19. Bleed air valve switches - OPEN and reestablish
maximum differential pressure.
20. Left bleed air valve switch - ENVIR OFF.
21. Slowly retard the right power lever to flight idle
and determine the minimum N1 required to
maintain cabin pressure. Cabin pressurization
should be maintained down to flight idle N1.
22. Left bleed air valve switch - OPEN.
23. Right bleed air valve switch - ENVIR OFF.
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