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1811D INSTRUCTION MANUAL
56-101-00164 Rev. F
SECTION 3
Apr / 19 / 13
Page 13 of 38
5. PRETESTS
1811D PANEL MOUNTED COMPONENTS
Figure 7
A. Pitot Pretest
Note: Refer to Figure 7 for panel-mounted components referenced by letters and
numbers in parentheses.
(1) Close all ports and valves.
(2) Pump pressure to 20 psi and vacuum to 20 inHg with PRESSURE pump (#A) and
VACUUM pump (#H).
(3) Open PRESSURE VALVE (#1) until AIRSPEED INDICATOR (#D) shows 300
knots. Close valve and monitor the airspeed for one (1) minute. (Airspeed should
not fall more than 2 knots.) Record leak rate.
(4) Open PRESSURE VENT (#2) valve to return airspeed to ambient pressure. Close
valve (#2).
Note: The term “ambient” refers to the existing atmospheric pressure in the area
where tests are performed.