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
as terrain, and is presented on the display as terrain (uses same coloring scheme).
The EGPWS utilize a worldwide Terrain Database.
For either worldwide or regional Terrain Databases, the Obstacle Database
currently covers cataloged obstacles 100 feet high or higher in North America and
portions of the Caribbean.
(11) PEAKS DISPLAY MODE
(a) As an enhancement to the “standard” EGPWS terrain display, the Peaks Mode
(when enabled by the installation configuration) allows terrain below the aircraft to
be viewed on the EGPWS terrain display during all phases of flight At altitudes
safely above terrain for the chosen display range, the terrain is displayed
independent of aircraft altitude emphasizing the highest and lowest displayed
elevations to provide enhanced situational awareness. This can be particularly
valuable to the flight crew in case of an unplanned descent or off-route deviation
and for previewing terrain prior to or during descent.
(b) The EGPWS terrain display uses colors and shading patterns corresponding to
the vertical displacement between terrain elevation and the current altitude of the
aircraft. With the “standard” display, terrain more than 2000 feet below the aircraft
For Training Purpose Only Printed:May 2005
B757-200Aircraft Recur rent Training Manual - 12 -
is not displayed typically leaving the terrain display blank during the enroute portion
of flight. The Peaks Mode Display adds additional density patterns and level
thresholds based on terrain elevations relative to the range and distribution of
terrain in the display area. The Peaks Mode is thus a “merged” display applicable
to all phases of flight.
(c) Within the Peaks Mode display, two elevation numbers indicate the highest and
lowest terrain currently being displayed. The elevation numbers indicate terrain in
hundreds of feet Above Sea Level (ASL). The terrain elevation numbers are
displayed with the “highest” terrain number on top, and the “lowest” terrain number
beneath it. The “highest” terrain number is shown in the same color as the highest
terrain color pattern on the display, and the “lowest” terrain number is shown in the
color of the lowest terrain color pattern shown on the display. A single elevation
number is displayed when there is no appreciable difference in terrain elevations
such as when flying over water (displayed blue on some display systems) or flat
terrain. The elevation numbers on the display are also an indication that the terrain
display is selected.
(12) GEOMETRIC ALTITUDE (GPS REQUIRED)
(a) Geometric Altitude is a computed pseudo-Corrected Barometric Altitude
(computed altitude “Above Sea Level” - ASL). This is designed to ensure optimal
operation of the EGPWS enhanced functions through all phases of flight and
atmospheric conditions. Geometric Altitude uses GPS Altitude, an improved
pressure altitude calculation, Radio Altitude, and Terrain and Runway elevation
data to reduce or eliminate errors potentially induced into Corrected Barometric
Altitude by temperature extremes, non-standard altitude conditions, and altimeter
miss-sets. Geometric Altitude also allows continuous EGPWS operations in QFE
environments without custom inputs or special operational procedures.
(13) WEATHER RADAR AUTOTILT (Optional)
(a) The EGPWS (-210-210 and later) provide an automatic Weather Radar tilt angle
capability. The Auto-Tilt function uses aircraft altitude above the terrain and the
terrain database to generate an optimum tilt angle for the Weather Radar. The
Auto-Tilt angle results in minimum ground clutter on the display while maintaining
the optimum weather detection capability. With manual tilt control, there can be
over-scan where weather cells and terrain are below the antenna beam scan
resulting in a blank display. Alternately, under-scan, where the antennas scan is
hitting the ground below the weather cells, results in ground clutter display. The
calculated tilt angle is transmitted on the ARINC 429-output bus (labels 061, 062,
063, 064, and 065) for any compatible Weather Radar system. See the appropriate
Part Number ICD for complete Label definitions.
(14) SYSTEM DISPLAY AND ANNUNCIATION
(a) In addition to the aural (voice) alerts provided over the cockpit speaker and
interphone system, the EGPWS drives cockpit annunciators with system status
and alert annunciations. For the displays (some EFIS and all Radar Indicators),
the terrain video is relay switched into the display system externally taking the
place of weather radar video. In this case, external switching and annunciation is
required. This is referred to as a “Bolt-On” display. The interface and display
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
飞机复训教材(15)
