Definition
A single charted fix on an instrument approach that serves two roles at once: it is both the Initial Approach Fix (IAF) — the point where the initial segment of the approach begins — and the Intermediate Fix (IF) — the point where the initial segment ends and the intermediate segment begins. On RNAV (GPS) approaches, an IF/IAF is typically used at the center fix of a T-shaped or Y-shaped approach design. When an aircraft is cleared direct to an IF/IAF from a course that aligns within an established angular tolerance (commonly within 90° of the final approach course), no procedure turn or course reversal is required, and the pilot continues straight into the intermediate segment.
Plain English
It's one waypoint on an approach that does two jobs. It marks the start of the approach and also the start of the next segment leading toward the runway. If you arrive at it from a reasonable angle, you don't need to do a turn-around maneuver — you just keep going inbound.
Context Anchor
Seen on instrument approach charts, especially where a course reversal or holding-pattern course reversal is published at the same fix.
Why Pilots Care
Recognizing a dual-purpose fix tells you the approach begins at that point and that a course reversal or hold is likely built into the procedure.
Analogy
It is like one doorway that works for two parts of a route: you may enter the route there, and later pass through the same doorway again as the route continues.
Intuition Check
Do not read “fix” as “repair.” In instrument flying, a fix is a known position. Do not assume IF/IAF means two separate points; it means one point with two charted roles.
Example Sentence 1
ATC cleared us direct to CENTR, the IF/IAF, and since we were arriving from the north within 90° of the final approach course, we continued straight in without a course reversal.
Example Sentence 2
Because the waypoint is labeled IF/IAF, I know I can cross it outbound and then reverse course to join the final approach course.