Specifications

SECTION III
MODEL 560 INSTRUMENTATION AND AVIONICS
AREA NAVIGATION
GNS-XL FLIGHT MANAGEMENT SYSTEM
The GNS-XL Flight Management System is a comprehensive navigation management system which
integrates multiple systems and sensors into an integrated whole, which is capable of precise navigation
and aircraft performance computations. The system takes information from various navigation sources
(DME, VOR, and GPS sensors), considers the strengths, weaknesses and signal strengths of each system
and sensor in use, and computes a most likely position for the airplane. The GPS sensor has priority
unless degraded sensor accuracy has been detected by the system. It accomplishes these computations
with a minimum of attention by the flight crew, and advises them of components or systems requiring
attention, as well as other irregularities such as loss of enough sensors to compute a valid position. In the
latter situation, if sensor loss endures over a set length of time, the system will enter DR (dead reckoning)
mode and so inform the pilot through a message on the control display unit (CDU).
The GNS-XL
provides steering information to the pilot through the IC-600 Integrated Display Guidance
Computer and Primary Flight Display (PFD). When connected to the autopilot, it provides roll steering
commands. The NAV computer additionally computes fuel flow information, providing a current fuel status
and airplane gross weight throughout the flight, if the fuel and gross weight are updated prior to takeoff.
The system also provides navigation data outputs which enable the active flight plan to be displayed
on the multifunction display (MFD).
The following components comprise the GNS-XL system: a control display unit (CDU) which houses
its own Global Positioning System (GPS) sensor, a configuration module unit, and an antenna.
The CDU is the heart of the system, possessing the computer, the VORTAC positioning unit (VPU),
the navigation data bank (NDB), and the memory capability, as well as the GPS receiver. The NDB
maintains 50,000 navigation points in its data base as well as up to 999 operator generated waypoints. Fifty
six flight plans with up to fifty waypoints each may be stored. The NAV data base must be updated every
twenty-eight days by means of a data transfer unit (DTU) or portable DTU. The connection for the DTU is
located in the forward end of the center pedestal.
The FMS will supply waypoint (WPT) information to the IC-600 Display guidance Computer for use in
micro air data computer vertical navigation (VNAV) computations, which are displayed on the multifunction
display(MFD). An advisory vertical navigation capability is also provided through the GNS-X
L
CDU. Vertical
waypoints may be programmed and viewed on the CDU, and used as indicators for climb and descent
points. The altitude changes may be programmed both with and without vertical path angles.
The CDU provides the pilot's interface with the system. It has a compact full alpha keyboard with a
color cathode ray tube (CRT) to provide system readouts and to accept pilot inputs into the system.
LIMITATIONS
The single installation of the GNS-XL, with GPS sensor, is not approved as a sole means of
navigation; therefore, when the GNS-XL is to be used as the primary means of navigation, or when coupled
to the autopilot, flight director or primary flight display (PFD), the navigation equipment required by the FARs
applicable to the specified type of operation being conducted must be installed and operating. Refer to the
airplane flight manual for additional limitations and operating information.
OPERATOR’S MANUAL
For detailed operating information, consult the GNS-XL Operator’s Manual, Report Number
006-08845-0000, Revision 6, issued July 1988 or later revision.
I 56OMB-01 Configuration AA 3-73