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
Note: When operating north of 82°N or south of 82°S using the ND PLAN mode,
the airplane position symbol changes to a circle with a "X" in the middle.
Note: If the IRS fails in a polar region, the EICAS message NAV INERTIAL
SYS displays and all autopilot and AFDS roll modes fail. When heading
information is restored by entry of a reference heading on the POS INIT
page, HDG SEL and HDG HOLD roll modes are restored. GPS continues
to provide navigation data to the FMC and active route information
displays on the ND. When operating in this degraded mode, heading on the
POS INIT page may be referenced to magnetic, true, or grid heading. The
heading display drifts significantly under these conditions. Periodic
updating of the heading reference on the POS INIT page should be
accomplished at least every 10 minutes.
FMC Polar Regions
73° N
170° W
80° W
TRUE
POLE
NORTH
60° S
160° E
82° S
TRUE
SOUTH
POLE
82° N
120° E
787 Flight Crew Operations Manual
Flight Management, Navigation -
Flight Management System
Operation
Boeing Proprietary 11.31.9
Navigation Performance
The FMC uses data from the navigation systems to accurately calculate the
position of the airplane. The current FMC position displays on line 1 of the POS
REF page 2. The primary source of update displays in parentheses above the FMC
position.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
U
2 3 0
0.12N M
.
2 / 4
PO S U P D A TE
ACT U A L 5.7 0 NM
ACT U A L . NM
ACT U A L 0.1 2 NM
R N P / A C T U A L D M E D M E
R A D I O L
GP S-I R U L
I R U L
FM C ( G P S-I R )
POS REF
ARM>
PDX SEA
AT/L0N>
035o/0 4 N M
000o /0.0 M
150o /3.9
N47o32.4 W122o18.6
/
<INDEX
N M
N
2
L
4 . 0 0
000o/0.0
035o/0.42NM
BRG/DIST
NAVIGATION SYSTEMS
FMC/GPS-IRU
RADIO L
150o/3.9NM
IRU L
ACTUAL 2.30NM
RADIO L
ACTUAL 5.70NM
IRU L
ACTUAL 0.12NM
FMC/GPS-IRU L
ACTUAL NAVIGATION PERFORMANCE
787 Flight Crew Operations Manual
Flight Management, Navigation -
Flight Management System
Operation
11.31.10 Boeing Proprietary
Navigation system positions display on the left side of lines 2 through 4. The
bearing/distance is from the FMC position to the individual navigation system
position.
The FMC position displays on the ND at the tip of the triangle. All other positions
display relative to the FMC. The RADIO position is shown above as a •, but is not
shown on the ND. The ACTUAL navigation performance circles shown above do
not display on the ND.
Actual Navigation Performance
Actual navigation performance (ANP) is the FMC current computed position
accuracy. It is titled ACTUAL and displays on the POS REF page 2 for the
navigation system displayed in title line 1. ACTUAL navigation performance is a
circular prediction centered at the FMC position. Airplane position is estimated to
be within this ACTUAL navigation performance circle 95 percent of the time.
After a manual position update, the ACTUAL navigation performance of the
FMC changes to the ACTUAL navigation performance of the selected navigation
system. In the example above, a manual position update to the IRU L system
would change the FMC ACTUAL navigation performance to 5.7 nm. The FMC
then updates from the best available navigation system and eventually, the manual
update has no effect on position calculation. Some automatic updates can be
inhibited; GPS, VOR/DME and DME/DME updates on POS REF page 3 and
VOR/DME updates on the REF NAV DATA page. Inertial updates can not be
inhibited.
Required Navigation Performance
Required Navigation Performance (RNP) is the navigation accuracy required for
operation within a defined airspace. It is expressed in nautical miles. RNP values
have been published for areas of operation around the world. Operations in these
areas require on–board navigation systems to alert the flight crew if ANP exceeds
RNP. The FMC supplies a default RNP value for takeoff, en route,
oceanic/remote, terminal, and approach phases of flight. The flight crew may enter
an RNP value, if required. RNP displays on POS REF page 2.
Lateral Navigation (LNAV)
LNAV provides steering commands to the next waypoint or the selected route
intercept point. When armed on takeoff, LNAV engages at or above 50 feet, when
laterally within 2.5 nautical miles of the active route leg. FMC LNAV guidance
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
787机组操作手册Flight Crew Operations Manual 3(24)
