When #TOC is the TO Waypoint:
The pilot may obtain range and ETE to any altitude above the aircraft
during a climb.
VNAV Key - DEPRESS
to display VNAV Page 1.
DEPRESS to position
the cursor over the
#TOC altitude field.
Alternate Altitude -
may be above or below
the altitude pre-select
value, but must be
above the current baro
ENTER Key - DEPRESS
and observe the change
in RANGE and ETE.
Repeat steps 2 thru 4 to
return to previous #TOC
Top of Descent (#TOD)
The Top of Descent waypoint is the position where the aircraft inter-
cepts the descent path at the cruise altitude. The system calculates
the #TOD by establishing a valid Descent Reference Waypoint, then
uses either the CRUISE ALT entered by the pilot on the VNAV
DATA Page, or the Altitude Preselector setting, if available. The
default FPA maybe used in this calculation.
If no Descent Reference Waypoint with FPA and crossing altitude is
programmed, the system will use the arrival airport and elevation
(ARP Reference Point, not a runway) and the default FPA to fix Top
of Descent as long as the active flight plan is not an AFIS flight plan.
NOTE: The default FPA may be used to establish #TOD, but no
Vertical Deviation Valid will occur until the FPA is actually loaded
from the VNAV WPT Page.
Flight Management System