56-101-01178 Revision K
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Note:
The “Current History” log file contains logged information for the current powered
ON session.
C.
In the final process of the Power ON initialization process, the Test Set will equalize the internal
pneumatic pressures contained within the internal 1811NG manifold and control vessels to
ambient. When this process has completed, the Test Set will then be vented to ambient
pressure and the display will indicate this.
D.
At this time the Test Set is ready for the hoses to be attached to the PITOT (Pt)
and STATIC
(Ps)
ports.
E.
As mentioned earlier, it is standard practice and highly recommended to perform a Test Set
Leak Test.
It is preferred that the complete aircraft hook-up configuration be assembled with all hoses and
manifolds to result in the most comprehensive leak test of all components prior to attaching
adapters to aircraft ports. Install plugs/caps in place of each Nav-Aids to allow leak testing of
the hoses, fittings and manifold if applicable.
At a minimum, perform the leak test with the hoses attached to the Test Set and with the other
end of the hoses capped.
This process will provide the most accurate leak test results and allow the user to establish a
baseline regarding what is the leak rate of the Test Set and hose combination prior to interfacing
with the aircraft or instrument under test.
6. OPERATING MODES
A.
The 1811NG has two pneumatic control modes of operation, (1) the default mode: 2-
channel (Ps & Pt) mode and (2) 1-channel: Pt-Only mode which the user can select by
following this Menu sequence: Main Menu, Page 2, Additional Functions, Control Mode.
B.
The 1811NG when powered ON after the initialization process has completed will always
be configured into the default 2-channel (Ps & Pt) mode. The 2-channel mode is by far the
most common configuration used while working with aircraft Pitot- Static systems and
Aeronautical instruments. In the 2-channel mode, the STATIC (Ps) port is used to both
measure and simulate the ALT, pressure altitude equivalent pressures while the PITOT
(Pt)
port
is used to measure and simulate the CAS “calibrated airspeed” equivalent
pressures. At all times, the displayed value for pressure altitude
“ALT” (ft or m) is
computed based on a
Baro
setting of
29.9213
inHg (
1013.25
mb).
Note:
Always verify that the Aircraft/Instrument has Baro Set at 29.9213 inHg (1013.25
mb).
Note:
The Baro setting value cannot be changed.
C.
The Pt-Only mode can be used to drive an Airspeed or MACH indicator that has its
STATIC (Ps)
port left vented to ambient (local barometric pressure). When the single
channel Pt-Only mode is selected the 1811NG will perform a Go To Ground function
before transitioning into this mode to ensure the Test Set Ps port is at ambient barometric
pressure, and at the conclusion of the Go To Ground function the Test Set will leave the
STATIC (Ps)
port vented to ambient pressure while driving the PITOT (Pt)
port to the
Target pressures specified by the user.