(2)
Navigation and position determination
(3)
Air data and navigation sensor management
(4)
Flight planning
(5)
Guidance and steering, both laterally and vertically
(6)
Self test
C. The basis of the FMCS capabilities is in the FMC program software. The software includes a performance data base and a navigation data base. Aerodynamic and engine performance models of the airplane are stored in the performance data base. The stored information is used to predict performance characteristics that govern the airplane optimal vertical profile. The navigation data base contains all information required for operation in a specified geographic area. This information includes navigation data on VORTAC stations, waypoints, airports, runways, enroute airways, and company routes. The navigation data is valid for a specified period of time. At the end of the time period a new navigation data base must be loaded into the FMC. When the airplane is on the ground a new navigation data base can be loaded into the FMC, by means of an external portable data loader. The program software also includes the logic that commands the digital flight control system, and the auto throttle. Sensor systems on the airplane provide inputs of air data, navigation, and airplane performance parameters. These inputs are received and checked by the FMCS, and then used for the refreshment of guidance information, which commands automatic flight controls and radio navigation system tuning.
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AND A SINGLE FMC ú CONFIG 1 ú 04 Page 9 ú Mar 15/95
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
737-300/400/500MAINTENANCE MANUAL
D. Through manipulation of the Control Display Unit (CDU) keyboard keys, the operator controls and selects the operating modes of the Flight Management Computer (FMC). In addition, through manipulation of the keys the operator may obtain a large selection of advisory data concerning the present state of the airplane. Also the operator may obtain data on other flight options they may wish to pursue. The CDU data appears on a cathode-ray tube screen. The cathode-ray tube permits information to be presented in a clear and concise fashion. Through CDU operating and data entry procedures, and through the use of plain text, the functional displays of the FMCS are formed into a cohesive group of CDU pages. These pages lead the pilots through preflight and inflight operation of the system.
E. The FMCS provides guidance commands to the DFCS and to the A/T, as well as tuning commands to VOR and DME radio navigation systems. The FMCS also provides data for display on the electronic flight, air data, ground proximity, and engine instruments.
F. Present position, velocity, and heading data are produced by the Inertial Reference System (IRS). The FMCS combines these IRS data with range and bearing from DME and VOR stations, for the best determination of airplane present position, velocity and track.
G. Built-In-Test-Equipment (BITE) is a function of the FMCS. The BITE function provides continuous monitoring of the Flight Management Computer (FMC) and Control Display Unit (CDU). Also BITE provides continuous monitoring of sensors and components that interface with the FMCS. When the airplane is on the ground the BITE also performs the task of overall FMS testing, upon demand by maintenance personnel. The CDU acts as the focal control and display when testing and monitoring the operational readiness status of the FMCS, DFCS, A/T, IRS and EFIS. Fault histories of the various sensor systems are also tracked and stored for later reference.
3. System Interface (Figs. 2 and 3)________________
A. Flight Management Computer (FMC)
(1)
The FMC performs the computational, logical, and input/output navigation processing required by the guidance flight planning and performance function. The outputs of the FMC are in ARINC 429 digital format.
(2)
Power for the computer is provided by a power supply unit. The unit is a subassembly of the computer chassis. The power supply is designed for 115-volts, 400-Hz, single phase input power.
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本文链接地址：737-300 400 500 AMM 飞机维护手册 导航 NAVIGATION 5(28)
