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
not required.
e) Pilots may apply an offset outbound at the oceanic entry point and must return to centreline
prior to the oceanic exit point.
f) Aircraft transiting radar-controlled airspace mid-ocean should remain on their already
established offset positions.
g) There is no ATC clearance required for this procedure and it is not necessary that ATC be
advised.
h) Voice Position reports should be based on the waypoints of the current ATC clearance and
not the offset positions.
Monitoring during Distractions from Routine
8.5.4 Training and drills should ensure that minor emergencies or interruptions to normal routine
are not allowed to distract the crew to the extent that the navigation system is mishandled.
8.5.5 If during flight the autopilot is disconnected (e.g. because of turbulence), care must be taken
when the navigation steering is re-engaged to ensure that the correct procedure is followed. If the system in
use sets specific limits on automatic capture, the across-track indications should be monitored to ensure
proper recapture of the programmed flight path/profile.
NORTH ATLANTIC MNPSA OPERATIONS MANUAL CHAPTER 8
NAT MNPS 52 Edition 2008
8.5.6 Where crews have set low angles of bank, perhaps 10° or less, say for passenger comfort
considerations, it is essential to be particularly alert to possible imperceptible departures from cleared track.
Avoiding Confusion between Magnetic and True Track Reference
8.5.7 To cover all navigation requirements, some operators produce flight plans giving both
magnetic and true tracks. However, especially if crews are changing to a new system, there is a risk that at
some stage (e.g. during partial system failure, re-clearances, etc.), confusion may arise in selecting the
correct values. Operators should therefore devise procedures which will reduce this risk, as well as ensuring
that the subject is covered during training.
8.5.8 Crews who decide to check or update their LRNSs by reference to VORs should remember
that in the Canadian Northern Domestic Airspace these may be oriented with reference to true north, rather
than magnetic north.
Navigation in the Area of Compass Unreliability
8.5.9 As aircraft move towards the Earth’s North magnetic pole the horizontal field strength
reduces and the ability of the compass to accurately sense magnetic North is reduced. It is generally
recognised that when the horizontal magnetic field strength falls below 6000 nanotesla, the magnetic
compass can no longer be considered to be reliable. Moreover, when the horizontal magnetic field strength
falls below 3000 nanotesla, the magnetic compass is considered to be unuseable. Within MNPS airspace the
North West of Greenland is an area of Compass Unreliability and adjoining areas of Canadian airspace
include areas where the magnetic Compass is Unuseable. En route charts for the North Atlantic and North
Polar areas show the areas where the compass is either unreliable or unuseable.
8.5.10 In areas where the compass is unreliable or unuseable, basic inertial navigation requires no
special procedures. Different manufacturers may offer their known solutions to the special problems existing
in such areas. However, such solutions should not involve the use of charts and manual measurement of
direction.
8.5.11 Furthermore, Operators/Pilots are reminded that before operating in an area of
Compass Unreliability they are responsible for checking with their State Authorities whether specific
regulatory approval or training is required.
Deliberate Deviation from Track
8.5.12 Deliberate temporary deviations from track are sometimes necessary, usually to avoid severe
weather; whenever possible, prior ATC approval should be obtained (See para 11.4). Such deviations have
often been the source of gross errors as a consequence of failing to re-engage the autopilot with the
navigation system. It should also be noted that selection of the 'turbulence' mode of the autopilot on some
aircraft may have the effect of disengaging it from the aircraft navigation system. After use of the turbulence
mode, extra care should be taken to ensure that the desired track is recaptured by the steering navigation
system.
8.6 POST-FLIGHT PROCEDURES
Inertial Navigation System Accuracy Check
8.6.1 At the end of each flight, an evaluation of accuracy of the aircraft's navigation systems
should be carried out. Equipment operating manuals specify maxima for radial errors before a system is
considered to be unserviceable. For early gimballed-platform inertial systems these are in the order of 2 NM
per hour. One method used to determine radial error is to input the shutdown ramp position; in other systems
error messages are output giving differences between raw inertial reference positions and computed radio
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
航空翻译14(45)
