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Old June 18th 06, 10:27 PM posted to rec.aviation.ifr
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Default procedure turns revisited

Greg Esres wrote:
ATC may clear aircraft that have filed an Advanced RNAV
equipment suffix to the intermediate fix when clearing aircraft for an
instrument approach procedure.

How does this jibe with the letter of interp requiring an a/c to use
an IAF or be vectored to final. Will this language be added to the
.65 so it can be said to be approved by the Administrator?


It was added to 7110.65R this past February.

Here is the new portion of 7110.65R, 4-8-1:

"Area Navigation (RNAV)
Standard Instrument Approach Procedures may
begin at an Intermediate Approach Fix for aircraft
that have filed an Advanced RNAV equipment suffix
when the conditions of subpara b4 are met."

And, here is the background material for the change in the back of 7110.65R:

BACKGROUND: Currently, paragraph 4−8−1 provides two methods for clearing
aircraft for a Standard Instrument
Approach: 1) clear the aircraft to the Initial Approach Fix (IAF) (or
Intermediate Fix (IF) when no IAF is depicted), or 2)
vector the aircraft to the final approach course. These procedures
create undue delay to pilots and air traffic control under
certain conditions. When an aircraft utilizing Area Navigation (RNAV) is
aligned with the final approach course and at an
altitude not requiring abnormal descent to the final approach fix, air
traffic must either clear the aircraft to an IAF or vector the
aircraft to the final approach course.
RNAV aircraft are capable of flying direct to a fix or waypoint with
more precision than a radar vector. A direct−to clearance
eliminates variables of aircraft drift when changing altitudes and/or
airspace when a strong wind shear is present. A radar
vector to a typical RNAV approach would place the aircraft within 2
miles of the IF. This requires the controller to monitor the
aircraft in variable wind conditions to ensure it does not intercept the
final approach course prior to the IF. The final approach
course does not extend beyond the IF as a radial on a conventional approach.
There are several supporting examples permitting RNAV aircraft to be
cleared direct to an IF to execute an instrument
approach procedure. FAA Order 8260.3B, United States Standard for
Terminal Instrument Procedures (TERPS),
paragraph 230, provides for an initial approach to be made along an arc,
radial, course, heading, radar vector, or combination
thereof when the IF is part of the en route structure. In this case, the
approach commences at the IF and a direct−to clearance
provides a course for the aircraft to fly. Aircraft may be cleared to
the IAF/IF for RNAV approaches. When a Terminal Arrival
Area (TAA) is depicted, most TAAs specify NoPT (No Procedure Turn) for
the straight−in segment. This permits aircraft to
fly the same segment of the instrument procedure as any RNAV approach
from the IF. 14 CFR Section 91.175(i) contains the
following statement: “When operating on an unpublished route or while
being radar vectored, the pilot, when an approach
clearance is received, shall, in addition to complying with Sec. 91.177,
maintain the last altitude assigned to that pilot until the
aircraft is established on a segment of a published route or instrument
approach procedure unless a different altitude is
assigned by ATC.” Aircraft are on an unpublished route when cleared
direct−to a fix or waypoint and the intermediate
segment defines the segment the aircraft must be established on for the
approach.
Issuing aircraft a direct−to clearance to the IF will enhance the
movement of aircraft in the terminal environment. Requiring
the controller to advise the pilot in advance of the clearance, limiting
the turn angle to intercept the intermediate segment,
accounting for descent along the approach and providing radar
monitoring, the procedure will ensure the pilot is able to
safely maneuver the aircraft for the approach.
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