Aeronautical Information Manual (AIM), page 384

Index   383 -- Page 384 -- 385

vectoring altitude (MVA) which provides at least
1,000 feet required obstruction clearance. The
AAUP may provide the MVA in the final approach
segment as X,XXX feet at (Name) Airport.
"TRAFFIC ALERT." If an aircraft enters the "NO TRANS-
GRESSION ZONE (NTZ)," the controller will breakout the
threatened aircraft on the adjacent approach. The phraseo-
logy for the breakout will be:
TRAFFIC ALERT, (aircraft call sign) TURN (left/right)
4. ILS PRM Glideslope Navigation. The pilot
may find crossing altitudes published along the final
approach course. If the approach geometry warrants
it, the pilot is advised on the AAUP that descending
on the ILS or LDA glideslope ensures complying
with any charted crossing restrictions.
5. SOIA and ILS PRM differences as noted
on the AAUP.

(a) ILS PRM, LDA Traffic (only published
on the AAUP when the ILS PRM approach is used
in conjunction with an LDA PRM approach to the
adjacent runway). To provide better situational
awareness, and because traffic on the LDA may be
visible on the ILS aircraft's TCAS, pilots are re-
minded of the fact that aircraft will be maneuvering
behind them to align with the adjacent runway. While

conducting the ILS PRM approach to Runway XXX,
other aircraft may be conducting the offset LDA PRM
approach to Runway XXX. These aircraft will ap-
proach from the (left/right) rear and will realign with
Runway XXX after making visual contact with the
ILS traffic. Under normal circumstances, these air-
craft will not pass the ILS traffic.

(b) SOIA LDA PRM Items. The AAUP sec-

tion for the SOIA LDA PRM approach contains most

information found in the ILS PRM section. It replaces

certain information as seen below and provides pilots

with the procedures to be used in the visual segment

of the LDA PRM approach from the LDA MAP until


(c) SOIA LDA PRM Navigation (replaces
ILS PRM (4) and (a) above). The pilot may find
crossing altitudes published along the final approach
course. The pilot is advised that descending on the
LDA glideslope ensures complying with any charted
crossing restrictions. Remain on the LDA course un-

til passing XXXXX (LDA MAP name) intersection
prior to maneuvering to align with the centerline of
Runway XXX.
(d) SOIA (Name) Airport Visual Segment
(replaces ILS PRM (4) above). Pilot procedures for
navigating beyond the LDA MAP are spelled out. If
ATC advises that there is traffic on the adjacent ILS,
pilots are authorized to continue past the LDA MAP
to align with runway centerline when:

(1) the ILS traffic is in sight and is expected
to remain in sight,
(2) ATC has been advised that "traffic is in
sight." (ATC is not required to acknowledge this
(3) the runway environment is in sight.
Otherwise, a missed approach must be executed.
Between the LDA MAP and the runway threshold, pi-
lots conducting the LDA PRM approach are re-
sponsible for separating themselves visually from
traffic conducting the ILS PRM approach to the adja-
cent runway, which means maneuvering the aircraft
as necessary to avoid that traffic until landing, and
providing wake turbulence avoidance, if applicable.
Pilots maintaining visual separation should advise
ATC, as soon as practical, if visual contact with the
aircraft conducting the ILS PRM approach is lost and
execute a missed approach unless otherwise instruc-
ted by ATC.

e. Differences between Simultaneous ILS and

ILS PRM or LDA PRM approaches of import-
ance to the pilot.
1. Runway Spacing. Prior to simultaneous
close parallel approaches, most ATC directed break-
outs were the result of two aircraft in-trail on the same
final approach course getting too close together. Two
aircraft going in the same direction did not mandate

quick reaction times. With PRM closely spaced ap-

proaches, two aircraft could be alongside each other,

navigating on courses that are separated by less than

4,300 feet. In the unlikely event that an aircraft "blun-

ders" off its course and makes a worst case turn of 30

degrees toward the adjacent final approach course,

closing speeds of 135 feet per second could occur that
constitute the need for quick reaction. A blunder has
to be recognized by the monitor controller, and
breakout instructions issued to the endangered air-
craft. The pilot will not have any warning that a
breakout is imminent because the blundering air-
craft will be on another frequency. It is important

5-4-48 Arrival Procedures

Page 384 of the Aeronautical Information Manual (AIM.pdf)
AIM: Official Guide to Basic Flight Information and ATC Procedures

Index   383 -- Page 384 -- 385