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Track Reversal and Racetracks
8.41Requirement. If a straight-in approach is not possible (or feasible), a procedure may be established using a facility on the aerodrome that serves both as the IAF and the MAPt. In this case, some form of track reversal procedure will be required in which the aircraft is flown outbound from the facility on a defined track, and then turned to fly inbound back towards the facility. This may be a procedure turn or a base turn.
8.42Procedure Turn. A procedure turn is defined as a turn from outbound to inbound in which the tracks flown are reciprocal. There are two types:
Approach Procedures 8
Figure 8.17 Track reversal - procedure turn
8.43 45°/180° Procedure Turn. This requires track guidance to a point (timed or DME) where a 45° turn is made followed by a straight leg of either 1 minute (category A or B aircraft) or 1 minute and 15 seconds (category C, D and E). At the end of the timed leg a rate 1 turn is made through 180° to bring the aircraft into a position to intercept the reciprocal of the outbound track at an interception angle of 45°.
CAT A and B = 1 min |
CAT C, D and E = |
1 min 15 sec |
45°/180° Procedure Turn |
Figure 8.18 45°/180° - procedure turn
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8.44 80°/260° Procedure Turn. This requires track guidance to a point (timed or DME) where an 80° rate 1 turn is made followed immediately by an opposite direction 260° rate 1 turn. In still air, this should bring the aircraft on to the reciprocal of the outbound track. Also in still air, the procedure should take exactly 2 minutes.
Procedures Approach 8
Start of turn defined by fix or may be timed
80°/260° Procedure Turn
Figure 8.19 80°/260° - procedure turn
Figure 8.20 Procedure turn shown on an approach plate
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8.45 Base Turn. Where accurate outbound track guidance can be provided by an NDB or VOR, a base turn can be specified where the inbound track is not the reciprocal of the outbound track. The specified outbound track is followed to a predetermined point at which a rate 1 turn is made so that the aircraft rolls out on the required inbound track.
End of outbound leg may be timed or defined by DME
Base Turn
Figure 8.21 Base turn
Figure 8.22 Base turn shown on an approach plate
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8.46 Racetrack Procedure. A racetrack consists of a turn from the inbound track through 180° at the facility or a fix after which, the outbound leg is flown to a point defined by time or a fix at which another turn through 180° is made to bring the aircraft back on to the inbound track. It is used where aircraft are required to enter a holding pattern prior to commencing the instrument procedure, and where the orientation of the holding pattern does not permit either a procedure turn or a base turn to be used. It will normally be specified as an ‘alternate procedure’ and specific instructions will be included on the plate.
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procedure turn or base turn |
turn procedure |
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‘Racetrack’ is an extension of the outbound leg to a defined fix, where an inbound turn is commenced
Figure 8.23 Racetrack procedure
Figure 8.24 Racetrack shown on an approach plate
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