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
be checked before inertial systems are aligned and the position should be recorded in the flight log and/or
Master Document. It is recommended that subsequent 'silent' checks of the present position and of the
inertial velocity outputs (e.g. ground speed registering zero) be carried out independently by both pilots
during (an early stage of) the pre-flight checks and again just before the aircraft is moved. Any discrepancies
should be investigated.
8.3.2 With regard to the insertion of the initial co-ordinates whilst on the ramp, the following
points should be taken into account:
in some inertial systems, insertion errors exceeding about one degree of latitude will
illuminate a malfunction light. It should be noted that very few systems provide protection
against longitude insertion errors.
at all times, but particularly in the vicinity of the Zero Degree E/W (Greenwich) Meridian or
near to the Equator, care should be taken to ensure that the co-ordinates inserted are correct.
(i.e. E/W or N/S).
NORTH ATLANTIC MNPSA OPERATIONS MANUAL CHAPTER 8
NAT MNPS 45 Edition 2009
System Alignment
8.3.3 The alignment of inertial systems must be completed and the equipment put into navigation
mode prior to releasing the parking brake at the ramp. Some systems will align in about 10 minutes, others
can take 15 minutes or more; expect alignment to take longer in extreme cold or at higher latitudes or when
the aircraft (and hence the inertial platform) is buffeted by winds or rocked during cargo loading. A rapid
realignment feature is sometimes provided but should only be used if, during an intermediate stop, it
becomes necessary to increase the system accuracy. The aircraft must be stationary during rapid realignment
which typically will take about one minute.
8.3.4 To ensure that there is adequate time for the initial alignment, the first crew member on the
flight deck should normally put the inertial system(s) into the align mode as soon as practicable.
GNSS (GPS) Systems
8.3.5 As with all LRNS operations, GPS LRNS operations must be approved by the State of the
Operator (or the State of Registry for International General Aviation operations) as part of the MNPS
operational approval. When both the LRNSs required for unrestricted MNPS operations are GPSs the
approval of their operation will include the requirement to carry out Pre-Departure Satellite Navigation
Prediction Programmes (as shown below). When only one of the two LRNSs required is a GPS, State
Authorities vary as to whether they require their operators to conduct such pre-departure programmes.
Satellite Availability
8.3.6 Given suitable geometry:
- Four satellites are required to determine 3-D position;
8.3.7 For Receiver Autonomous Integrity Monitoring (RAIM) purposes:
- Five satellites are required to detect the presence of a single faulty satellite;
8.3.8 For Fault Detection and Exclusion (FDE) purposes:
- Six satellites are required to identify a faulty satellite and exclude it from participating in
further navigation solution calculations. (Note that an FDE algorithm is normally
associated with a RAIM algorithm).
Note: the above numbers of satellites (for RAIM and FDE purposes only) may in each case be
reduced by one if barometric aiding is used.
Satellite Navigation Prediction
8.3.9 When so required, operators intending to conduct GPS navigation in MNPS Airspace must
utilise a Satellite Navigation Availability Prediction Programme specifically designated for the GPS
equipment installed. This prediction programme must be capable of predicting, prior to departure for flight
on a "specified route"*, the following:
a) Any loss of navigation coverage (meaning that less than 3 satellites will be in view to the
receiver);
and
b) Any loss of the RAIM function and its duration.
*Note: "specified route" is defined by a series of waypoints (to perhaps include the route to any
required alternate), with the time between waypoints based on planned speeds. Since flight
planned ground speeds and/or departure times may not be met, the pre-departure prediction must
be performed for a range of expected ground speeds.
8.3.10 This prediction programme must use appropriate parameters from the RAIM algorithm
employed by the installed GPS equipment. In order to perform the predictions this programme must provide
NORTH ATLANTIC MNPSA OPERATIONS MANUAL CHAPTER 8
NAT MNPS 46 Edition 2009
the capability to manually designate satellites that are scheduled to be unavailable. Such information is not
included in the GPS almanac or ephemeris data in the navigation message (i.e. the GPS receiver does not
receive this information). Information on GPS satellite outages is promulgated via the U.S. NOTAM Office.
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(120)
