Approach Procedures — Page 185, Lesson 264

Right, let's get into the next piece of the approach procedures chapter. We've covered the basic segments, so now we're looking at what happens when a straight-in approach just isn't possible or feasible. The requirement here is straightforward. If you can't fly a straight-in approach, the procedure may be established using a single facility on the aerodrome that serves as both the Initial Approach Fix, the IAF, and the Missed Approach Point, the MAPt. Because you're using one facility for both, you need some form of track reversal procedure. The aircraft flies outbound from that facility on a defined track, then turns to fly inbound back towards it. This reversal can be done as either a procedure turn or a base turn. Let's focus on the procedure turn. The definition is precise: a procedure turn is a turn from outbound to inbound in which the tracks flown are reciprocal. Reciprocal means the inbound track is the exact opposite direction of the outbound track. There are two types we need to know. The first is the 45°/180° procedure turn. This requires track guidance to a point, which can be timed or DME-based. At that point, you make a 45° turn, then fly a straight leg. The length of that leg depends on your aircraft category. For category A or B aircraft, it's 1 minute. For categories C, D, and E, it's 1 minute and 15 seconds. At the end of that timed leg, you make a rate 1 turn through 180°. A rate 1 turn is a standard 3° per second turn. That 180° turn brings the aircraft into a position to intercept the reciprocal of the outbound track at an interception angle of 45°. The second type is the 80°/260° procedure turn. This also requires track guidance to a point, timed or DME. At that point, you make an 80° rate 1 turn, followed immediately by an opposite direction 260° rate 1 turn. In still air, this should bring the aircraft onto the reciprocal of the outbound track. Also in still air, the entire procedure should take exactly 2 minutes. The start of the turn is defined by a fix or may be timed. So to summarise the key contrast: the 45°/180° has that timed straight leg between the turns, while the 80°/260° is two continuous turns with no straight leg in between. Both achieve the same goal—reversing your track to get you inbound—but through different geometry.