TM  1-1510-225MTF
CHAPTER  4.  SPECIAL
PROCEDURES
4-1.  GENERAL.  I-his  chapter  contains  the  special  proce-
dures that were referenced in Chapter 2.
PRESSURIZATION
1.  Before  takeoff:
(a) Cabin controller - Set for a 5000 foot cabin alti-
tude.
(b) Cabin controller RATE knob - Set to mid posi-
tion.
(c) BLEED AIR VALVES switches (2) - OPEN.
(d) CABIN PRESS DUMP switch - PRESS.
2.  After  takeoff  -  Initiate  a  climb  to  10,000  to  12,000
feet pressure altitude.
3. Cabin rate-of-climb indicator - Monitor for a smooth
transition   from   an   unpressurized   to   a   pressurized
cabin.
4.   Cabin   controller   RATE   knob   -   Set   to   maximum.
Monitor the cabin rate of climb for a rate of between
1500 and 2500 feet per minute.
5.  Cabin  controller  RATE  knob  -  Set  to  mid  position.
Monitor  the  cabin  rate  of  climb  for  a  rate  of  350  to
650 feet per minute.
6.   Cabin   controller   RATE   knob   -   Set   to   minimum.
Monitor the cabin rate of climb for a rate of 50 to 300
feet per minute.
7.   Cabin   altimeter   -   Check   that   the   cabin   altimeter
needle stabilizes at 4600 to 5400 feet while the cabin
differential pressure needle continues to increase.
8.  CABIN  CONTROLLER  -  Set  to  10,000  feet.  Cabin
altitude should reach 9600 to 10,400 feet.
9. CABIN PRESS switch - DUMP, when cabin altitude
approaches aircraft altitude.
4-l