Embraer EMB145, Operation Manual

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SUPPLEMENTARY
PROCEDURES
ENVIRONMENTAL
AIRPLANE
OPERATIONS
MANUAL
1-02-79
Page
30
Code
01 REVISION 41
Copyright © by Embraer. Refer to cover page for details.
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PRESSURIZATION IN MANUAL MODE
This section contains additional information to assist pressurization
operation in manual mode. If necessary, consult AOM Section 2-14-15
- Pressurization System. Procedures are intented to supplement the
procedures published in the QRH.
Procedures herein are valid for dispatch with the pressurization
system automatic mode inoperative (MEL item 21-30-00) or in case of
loss of automatic mode in flight. For rapid loss of pressurization, refer
to the RAPID CABIN DEPRESSURIZATION procedure in the QRH.
GENERAL
It has been observed that cabin altitude indication may vary under
manual mode operation. Therefore, it is recommended to wait until
cabin altitude indication stabilizes, when the manual controller should
be operated as required to control cabin altitude.
In manual mode, crew selection of the cabin rate and proper
monitoring of cabin differential pressure is required to maintain
appropriate cabin pressurization. With relation to the 12 o’clock
position, clockwise rotation of the controller will induce a positive cabin
rate of climb, and a counter-clockwise rotation will induce a negative
cabin rate of climb.
The manual controller gain is very sensitive and the response time to
the command may take few seconds. Avoid fast and large
displacement of the controller.
After making cabin rate changes, wait a few seconds for the system to
stabilize and then verify if the result is the desired one.
If necessary repeat the procedure until the desired result is achieved.
RECEIVING/BEFORE DOOR CLOSING
Pressurization Manual Controller.................................. FULL UP
Pressurization Mode Selector Button ........................... MANUAL
Check that MAN inscription illuminates inside the button.
Pack .............................................................................. ONLY ONE
PACK ON
This setting allows one outflow valve to be fully open and reduces
cabin airflow, thus avoiding uncomfortable pressure changes when
the doors are closed or during engine starts.