Boeing 787-8 - Tuning and Control Panel - Normal Operation; Tuning and Control Panel - ATP Inoperative

787 Flight Crew Operations Manual
DO NOT USE FOR FLIGHT
Flight Management, Navigation -
Navigation Systems Description
Copyright © The Boeing Company. See title page for details.
D615Z003-TBC 11.20.15
If the ATP becomes inoperative the Transponder/TCAS modes can be set through
the backup function of the TCP.
Transponders provide selective interrogation and downlink information, such as
flight number, airspeed or groundspeed, magnetic heading, altitude, GPS position,
etc. Some airports use transponder information to monitor airplane position on the
ground when the transponder is active (mode selector not in STANDBY or OFF).
Transponder enhancements also enable air traffic controllers in some areas of the
world to use Automatic Dependent Surveillance-Broadcast (ADS-B). TCAS
modes should not be used on the ground for ground tracking.
Tuning and Control Panel - Normal Operation
The transponder control pages on the TCP are accessed by selecting the XPDR
mode select key.
The TCP controls:
• Mode A numeric code
• ATC Ident function
• TCAS envelope (Above, Normal, or Below)
• Altitude Mode (Absolute or Relative)
• Transponder select (Left or Right)
The Captain and First Officer TCPs share control of the:
• XPDR code
• IDENT function
• left or right side selection
Any changes made are also reflected on the center and cross-side TCPs. TCAS
envelope and altitude settings control only the on-side TCAS display, and changes
on one TCP are not reflected on the cross-side TCP.
The center TCP can control both left and right side transponders. When XPDR is
selected from the center TCP the flight crew is prompted to select either Captain
(left) or First Officer (right).
Should the on-side transponder fail, the TCP automatically switches to the
cross-side transponder. A status message is logged and a status prompt displayed.
Should both transponders fail, the EICAS advisory message TRANSPONDER is
displayed. If altitude reporting fails, the transponder can be switched to the
alternate altitude source. (Refer to Traffic Alert and Collision Avoidance System
(TCAS) in Chapter 15, Section 10, for additional information.)
Tuning and Control Panel - ATP Inoperative
If the ATP fails, the EICAS advisory message TRANSPONDER PANEL is
displayed and the transponder and TCAS modes must be set using the TCP.
August 14, 2009