Figure 3-11 TACAN Minimums
TACAN approaches are usually flown from the IAF only for practice, or if two-way radio failure
has occurred. If radio communications and RADAR are available, most instrument approach
procedures (IAP) have four segments: the initial segment, the intermediate segment, the final
segment, and the missed approach segment (reference: OPNAVINST 3722.16_ "TERPS").
Clearance for an approach is clearance for ALL 4 segments of an
TACAN approaches are most frequently flown via radar vectors to the final approach course (see
TACAN Initial Approach Course Alignment
A "penetration" is the type of initial approach segment most often used in High Altitude IAPs.
The initial segment begins at the IAF. Most, but not all, approaches begin with a descent at the
IAF. If a High TACAN approach begins with a descent at the IAF, it is considered good practice
to begin the descent only after becoming established on the initial approach course. At times, an
aircraft will be cleared to an IAF on a course significantly different from the initial approach
course. In such cases, any one of three methods may be used to establish the aircraft on course,
as shown in Figure 3-12.