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ATCM 51-38 1 September 1977
Chapter 6
TRAFFIC PATTERNS AND LANDINGS

With the high volume of traffic associated with a training environment, traffic patterns and procedures must be designed which will maximise safety and training while minimising congestion and traffic conflicts. 

PATTERN AIRSPEEDS/ANGLE OF ATTACK (ADA)

The runway is the primary reference in the traffic pattern. The airspeed, angle of attack indicator and indexer lights are used as warnings of slow speed and approaching stall conditions.

A stall indication in the landing pattern may indicate one or more of the following conditions:

1. If on computed speed, an incorrect configuration may exist (forgot flaps).
2. An incorrect speed has been computed or reference speed marker incorrectly set.
3. Flying too slow an airspeed.
4. System malfunction (either AOA or airspeed).

A slow speed indication may indicate the need for the pilot to initiate a go-around unless he can determine that he is flying a safe controlled approach. Be aware the momentary flashing of the indexer lights will occur if pitch changes are rapid or erratic.

VASI (VISUAL APPORACH SLOPE INDICATOR)

The different VASI configurations are in use at UPT wings. Standard VASI has a 2.5 degree to 3 degree glide slope and a GPI generally 750 feet beyond the runway threshold coincidental to the ILS or PAR to that runway. Nonstandard VASI has a 3.5 degree glide slope and the glidepath intercept point is generally 450 feet short of the runway threshold. Nonstandard VSAI allows the pilot to hold an on-glidepath indication to a point just short of the runway threshold and deletes the requirement for "ducking under" the on-slope indications to touchdown with the first 1,000 feet of the runway. Nonstandard VASI indications for above, on, or below the proper glide slope are the same as for standard VASI as described in FLIP. The nonstandard VASI indications come into view in the last portion of the final turn and are valid throughout the final approach until approaching the flare point. Tests indicate that a position 1,000 feet from the overrun threshold is the average point where VASI is dropped from the pilot's cross-check in preparation for a normal VFR landing. The VASI is an approach aid only and must be used in conjunction with normal references to develop pilot judgment. If you follow VASI on-course throughout the flare and touchdown, a short landing (450 feet short of the runway threshold) will result.

NORMAL PATTERNS

Initial Approach, Downwind Leg, and Final Turn

Adjust all traffic patterns to compensate for wind conditions. Although the RSU broadcasts wind conditions, direction and velocity may vary at altitude. Appropriate items of the checklist may be accomplished prior to pitchout. Set the reference speed marker to the final approach speed. 

Normally, begin the pitchout between 1,000 feet beyond the approach end and 3,000 feet down the runway. The pitchout is a steep banked turn; bank angle will vary according to wind conditions. Rollout on the downwind with the necessary drift correction to maintain the desired flightpath and with an airspeed below 240 KIAS but not below final turn airspeed. 

Before beginning the final turn, check that the landing gear is down and locked and that the flaps have traveled a sufficient distance to ensure that an asymmetrical condition has not been encountered. Do not allow airspeed to decrease below final turn airspeed. Sixty percent flaps are normally used for touch-and-go practice while full flaps are desired for full stop landings.

To determine when to initiate the final turn use the runway references compensated for wind. You must have visual contact with a preceding aircraft in the final turn and/or a straight-in aircraft inside 4 miles to ensure that a normal size pattern will provide the necessary separation on final. Enter a 30 degree to 45 degree