Selecting a data option enables the scratchpad on the MFD and HUD; other data options are blanked
(Figure 28). New data is entered with the push-buttons on the data entry panel (DEP). When the ENT
push-button on the DEP is pressed, the scratchpad is removed, waypoint data is updated with the new
value, the option is unboxed, and the other blanked options are redisplayed. (Note: waypoint elevation is
only used for CCIP bombing computations; not for waypoint steering or time-to-go computations.)
Figure 28: WAYPOINT DATA ENTRY
Once the latitude, longitude, and magnetic variation of the navigation aid are entered as an active
waypoint the bearing and range of the fix can be entered as previously described in this FTI.
This phase consists of those activities occurring in the transition from enroute flight to approach and
includes procedures for holding and performing enroute descents.
Holding refers to the maneuvering of an aircraft in relation to a navigational fix. Holding patterns are
defined areas of airspace where aircraft could be required to hold en route, when awaiting clearance to
commence an approach, or after executing a missed approach. All aircraft given the same holding
instructions must fly the same pattern separated only by altitude. Holding is often required when weather
conditions are poor in a terminal area and traffic congestion occurs.
Two basic holding categories are flown in the T-45C: VOR only and TACAN/VOR DME. The difference
between the two is predicated on the use or availability of DME to identify the fixes and the limits of the
holding pattern. There are also two different types of holding patterns, standard and nonstandard.
Standard holding uses right turns in the pattern and nonstandard holding is flown using left turns in the
pattern. Determination of which category and type of holding to be flown is dictated either by a depiction