曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
from normal cockpit lighting circuits.
C. Standby Altimeter:
The standby altimeter provides an indication of airplane pressure altitude in
event of primary flight display failure or malfunction. Altitude is indicated in
twenty (20) foot increments within a range of one thousand (1,000) feet by
a pointer that moves in front of the circular scale on the face of the
instrument, making one revolution for every 1,000 feet. A drum-type
counter in the center of the instrument provides graphic indications of
altitude in hundred (100) and 1,000 foot increments. The local barometric
pressure in inches of mercury (Hg) or millibars (Mb) is set with the knob on
the lower corner of the instrument and displayed in windows in the
instrument face. See the illustration in Figure 1.
Like the standby airspeed indicator, the ARINC 429 connections necessary
to derive altitude information from the DADCs are not installed. A yellow
flag, labeled PNUE, is displayed at all times on the instrument, indicating
that this feature is not available.
The standby altimeter is powered by 28V DC from the Essential DC bus,
and uses only pitot/static input for altitude determination. It is internally
illuminated and has an electrically driven vibrator to smooth pointer
movement. If electric power is lost, a VIB flag is displayed on the
instrument and while indications will be valid, pointer movement may be
intermittent, requiring occasional manual tapping on the face of the
instrument during climb and descent.
D. Static Air Temperature / Total Air Temperature (SAT / TAT) System:
A heated Total Air Temperature probe is installed on the lower right forward
fuselage to provide actual air temperature to the DADCs. See Figure 2 for
a depiction of the probe. On the ground with electrical power and bleed air
available, the probe is aspirated by bleed air through a dedicated line
controlled by a solenoid operated valve that routes air into the probe
housing, venting the air through holes in the probe to induce outside air
OPERATING MANUAL
PRODUCTION AIRCRAFT SYSTEMS 2A-34-00
Page 3
October 11/01
Revision 5
flow over the temperature sensing element. Air flow through the probe
gives a more accurate reading of ambient conditions and avoids
temperature increases associated with the heating effects of sunlight.
Bleed air aspiration is controlled by the nutcracker (squat) switch system
and requires 28V DC from the Right Main DC bus. The TAT probe is
electrically heated when the airplane is airborne to prevent icing.
E. Digital Air Data Computer System (DADC):
Dual Honeywell AZ-810 Digital Air Data Computers (DADCs) are installed
in the forward avionics racks. The DADCs are connected to the pitot/static
system, with the pilot side pitot/static probe and ports connected to DADC
#1 and the copilot side pitot/static sensors connected to DADC #2. Both
DADCs are connected to the TAT probe for temperature data. The DADCs
use the pneumatic and temperature data to compute correct airspeed,
altitude, vertical speed, static source error correction (SSEC) and to send a
signal to the audible tone generator initiating the overspeed “cricket”
warning when airspeed reaches VMO/MMO. Other inputs used by the
DADCs are Angle of Attack (AOA), flap handle position, barometric setting
and pre-selected altitude. The DADCs formulate digital signals for
elements of the airplane avionics system. The DADCs communicate data
to the following:
• Electronic Display System
• Transponders
• Flight Recorder
• Flight Guidance Computer
• Fault Warning Computer
• Inertial Reference System
• Flight Management System
• Cabin Pressurization System
• Stall Barrier System
• Engine Pressure Ratio (EPR) Sensor
• Traffic / Aircraft Collision Avoidance System (TCAS / ACAS)
In order to maintain a continual crosscheck of system accuracy, it is
recommended that the pilot select DADC #1 as a data source, and the
copilot select DADC #2. Data source selection is made on the SENSOR
page of the Display Controller. In this configuration, each pilot has an
independent source for altitude, airspeed, AOA, vertical speed, SAT and
TAS on their respective PFDs and navigation displays. If both pilots select
the same DADC as data source, an amber annunciation is displayed on
both PFDs. (If the pilot PFD is selected to DADC 2, both PFDs would
display DADC 2 in amber in the upper right of the PFDs.)
Data source selection for the guidance panel altitude pre-select is a
function of the PFD command button (PFD-CMD). When the button
indicates L, the data source is DADC #1, when R is displayed, data comes
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
湾流4操作手册 Gulfstream IV Operating Manual 2(106)
