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AIM

10/12/17

5−4−20

Arrival Procedures

presence of a VDA does not change any nonprecision

approach requirements.

1. Obstacles may penetrate the visual segment

of an IAP that has a published VDA. When the VDA

is not authorized due to an obstacle penetration that

would require a pilot to deviate from the VDA

between MDA and touchdown, the VDA/TCH will

be replaced with the note “Visual Segment-

Obstacles” in the profile view of the IAP (See

FIG 5−4−14). Accordingly, pilots are advised to

carefully review approach procedures to identify

where the optimum stabilized descent to landing can

be initiated. Pilots that follow the previously

published descent angle below the MDA on

procedures with this note may encounter obstacles in

the visual segment.

2. The threshold crossing height (TCH) used to

compute the descent angle is published with the

VDA. The VDA and TCH information are charted on

the profile view of the IAP following the fix

(FAF/stepdown) used to compute the VDA. If no

PA/APV IAP is established to the same runway, the

VDA will be equal to or higher than the glide path

angle of the VGSI installed on the same runway

provided it is within instrument procedure criteria. A

chart note will indicate if the VGSI is not coincident

with the VDA. Pilots must be aware that the

published VDA is for advisory information only and

not to be considered instrument procedure derived

vertical guidance. The VDA solely offers an aid to

help pilots establish a continuous, stabilized descent

during final approach.

FIG 5−4−14

Example of a Chart Note

3. Pilots may use the published angle and

estimated/actual groundspeed to find a target rate of

descent from the rate of descent table published in the

back of the U.S. Terminal Procedures Publication.

This rate of descent can be flown with the Vertical

Velocity Indicator (VVI) in order to use the VDA as

an aid to flying a stabilized descent. No special

equipment is required.

4. A straight−in aligned procedure may be

restricted to circling only minimums when an

excessive descent gradient necessitates. The descent

angle between the FAF/stepdown fix and the Circling

MDA must not exceed the maximum descent angle

allowed by TERPS criteria. A published VDA on

these procedures does not imply that landing straight

ahead is recommended or even possible. The descent

rate based on the VDA may exceed the capabilities of

the aircraft and the pilot must determine how to best

maneuver the aircraft within the circling area in order

to land safely.

l. In isolated cases, an IAP may contain a

published visual flight path. These procedures are

annotated “Fly Visual to Airport” or “Fly Visual.” A

dashed arrow indicating the visual flight path will be

included in the profile and plan views with an

approximate heading and distance to the end of the

runway.