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
the aircraft will level off at 18000 ft and selected ALT mode will engage. To resume climb, select higher altitude (or cruise FL)
and push altitude selector.
CLB mode is used during climbs. It maintains target airspeed using aircraft pitch, with thrust xed at CLB.
DES mode follows computed descent vertical path. This path is automatically calculated by FMS and uses thrust setting near
IDLE.
If NAV managed lateral mode is active, the managed CLB mode will automatically engage when aircraft climbs above acceleration
altitude, which defaults to 1500 ft AGL.
When ight plan contains altitude constraints, the aircraft will level off at such constraints, and ALT CST mode will engage. As soon
as a waypoint with the constraint is passed, the climb or descent will continue automatically.
When cruise altitude is reached, the aircraft levels off and ALT CRZ mode engages. The descent doesn’t start automatically. To
initiate the descent when near Top of Descent point displayed on ND, change FCU altitude window to a lower altitude, and push the
altitude selector - this will engage managed DES mode. If DES mode is not engaged after passing the Top of Descent point, a white
“DECELERATE” message will appear under Flight Mode Annunciators on PFD.
Sometimes the computed descent prole can contain a steep segment and guidance will be unable to keep target speed even
using idle thrust. In this case, a white “MORE DRAG” message is displayed asking you to add more drag by partially extending
speed brakes.
When ying at cruise altitude and it is desired to change the cruise FL, select new altitude on FCU and push ALT selector knob. This
action will update the cruise FL entered in the FMS, and initiate ight level change.
Altitude acquire modes
The acquire modes, ALT*, ALT CRZ* and ALT CST*, provide the transition between previous vertical modes and altitude hold
(ALT / ALT CRZ / ALT CST) mode. When acquire modes engage, the speed guidance switches to SPEED or MACH, and vertical
speed is gradually decreased as aircraft approaches the level-off altitude.
Vertical mode reversions
Certain conditions or pilot actions will cause the active vertical mode to be switched to another mode. This happens in following
cases:
• If descending in V/S or FPA, and aircraft approaches maximum speed limit (Vmax), OP DES engages.
• If climbing in V/S or FPA, and aircraft approaches minimum speed limit (Vls), OP CLB engages.
• If climbing in OP CLB or EXP CLB, and FCU altitude window is changed to a value below current altitude, V/S is engaged
with current vertical speed.
• If descending in OP DES or EXP DES, and FCU altitude window is changed to a value above current altitude, V/S is engaged
with current vertical speed.
A319/320/321
Systems Manual
Phoenix Simulation Software P 38
REV 01 SEQ 001 AUTOFLIGHT
Vertical guidance (continued)
Speed Reference System
Speed Reference System (SRS) vertical mode is automatically engaged at takeoff or a go-around, ensuring optimum climb
performance. This mode commands aircraft pitch to maintain reference speed. During takeoff, this speed is V2+10. During
go-around, the reference speed is Vapp or speed existed at go-around initiation, whichever is higher.
The SRS mode automatically disengages and is replaced by CLB after passing acceleration altitude. This doesn’t happen, however,
if FCU altitude is set below acceleration altitude.
Approach and landing modes
LOC and G/S modes
These two modes are used for ILS approaches. Both modes are armed by pushing APPR button on FCU. LOC and G/S modes can
only be armed when an ILS frequency is tuned (automatically or manually). During localizer and glidesplope interception, LOC* or
G/S* modes are activated, which change to LOC and G/S after capture. Armed LOC and G/S modes can be disarmed by pressing
APPR button second time, if autoland procedure is not yet active.
When LOC and G/S are armed or active, second autopilot can be engaged for enhanced redundancy.
Autoland
Automatic landing is initiated with LOC and G/S modes engaged, at 400 ft above runway. The guidance mode controls on FCU
become locked until touchdown, autopilot disconnect or go-around initiation.
The LAND mode becomes active lateral and vertical mode. LAND mode maintains ILS localizer and glideslope. At about 40-50
feet, LAND mode is replaced by FLARE mode, which reduces vertical speed prior to touchdown. At about 10 feet, aural “RETARD”
call is heard which instructs the pilot to move thrust levers to IDLE position. At touchdown, ROLLOUT mode engages.
A319/320/321
Systems Manual
Phoenix Simulation Software P 39
REV 01 SEQ 001
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
PSS A319/A320/A321 Systems Manual 系统手册(14)
