FIG 5−4−14
Timed Approaches from a Holding Fix
ONE MINUTE
FLYING TIME
APPROXIMATELY 5 MILES
12:03 CLEARANCE RECEIVED
:04 INITIAL TIME
OVER FIX
1000 FT.
1000 FT.
1000 FT.
1000 FT.
:06 1/2
:07 REPORT
LEAVING FINAL
APPROACH TIME
:05 1/2
:05
30 SEC.
REPORT LEAVING
PREVIOUS ALTITUDE FOR
NEW ASSIGNED ALTITUDE
LOM LMM
AIRPORT
EXAMPLE−
At 12:03 local time, in the example shown, a pilot holding, receives instructions to leave the fix inbound at 12:07. These
instructions are received just as the pilot has completed turn at the outbound end of the holding pattern and is proceeding
inbound towards the fix. Arriving back over the fix, the pilot notes that the time is 12:04 and that there are 3 minutes to lose
in order to leave the fix at the assigned time. Since the time remaining is more than two minutes, the pilot plans to fly a race
track pattern rather than a 360 degree turn, which would use up 2 minutes. The turns at the ends of the race track pattern
will consume approximately 2 minutes. Three minutes to go, minus 2 minutes required for the turns, leaves 1 minute for level
flight. Since two portions of level flight will be required to get back to the fix inbound, the pilot halves the 1 minute remaining
AIM 8/5/04
5−4−28 Arrival Procedures
and plans to fly level for 30 seconds outbound before starting the turn back to the fix on final approach. If the winds were
negligible at flight altitude, this procedure would bring the pilot inbound across the fix precisely at the specified time of
12:07. However, if expecting headwind on final approach, the pilot should shorten the 30 second outbound course somewhat,
knowing that the wind will carry the aircraft away from the fix faster while outbound and decrease the ground speed while
returning to the fix. On the other hand, compensating for a tailwind on final approach, the pilot should lengthen the
calculated 30 second outbound heading somewhat, knowing that the wind would tend to hold the aircraft closer to the fix
while outbound and increase the ground speed while returning to the fix.
5−4−11. Radar Approaches
a. The only airborne radio equipment required for
radar approaches is a functioning radio transmitter
and receiver. The radar controller vectors the aircraft
to align it with the runway centerline. The controller
continues the vectors to keep the aircraft on course
until the pilot can complete the approach and landing
by visual reference to the surface. There are two types
of radar approaches: Precision (PAR) and Surveillance
(ASR).
b. A radar approach may be given to any aircraft
upon request and may be offered to pilots of aircraft
in distress or to expedite traffic, however, an ASR
might not be approved unless there is an ATC
operational requirement, or in an unusual or
emergency situation. Acceptance of a PAR or ASR by
a pilot does not waive the prescribed weather
minimums for the airport or for the particular aircraft
operator concerned. The decision to make a radar
approach when the reported weather is below the
established minimums rests with the pilot.
c. PAR and ASR minimums are published on
separate pages in the FAA Terminal Procedures
Publication (TPP).
1. A PRECISION APPROACH (PAR) is one
in which a controller provides highly accurate
navigational guidance in azimuth and elevation to a
pilot. Pilots are given headings to fly, to direct them
to, and keep their aircraft aligned with the extended
centerline of the landing runway. They are told to
anticipate glidepath interception approximately 10 to
30 seconds before it occurs and when to start descent.
The published Decision Height will be given only if
the pilot requests it. If the aircraft is observed to
deviate above or below the glidepath, the pilot is
given the relative amount of deviation by use of terms
“slightly” or “well” and is expected to adjust the
aircraft’s rate of descent/ascent to return to the
glidepath. Trend information is also issued with
respect to the elevation of the aircraft and may be
modified by the terms “rapidly” and “slowly”; e.g.,
“well above glidepath, coming down rapidly.” Range
from touchdown is given at least once each mile. If an
aircraft is observed by the controller to proceed
outside of specified safety zone limits in azimuth
and/or elevation and continue to operate outside these
prescribed limits, the pilot will be directed to execute
a missed approach or to fly a specified course unless
　
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