AIM
4/3/14
10−1−3
Helicopter IFR Operations
10
−
1
−
2. Helicopter Instrument Approaches
a.
Helicopters are capable of flying any published
14 CFR Part 97, Standard Instrument Approach
Procedures (SIAPs), for which they are properly
equipped, subject to the following limitations and
conditions:
1.
Helicopters flying conventional (non−
Copter) SIAPs may reduce the visibility minima to
not less than one half the published Category A
landing visibility minima, or
1
/
4
statute mile
visibility/1200 RVR, whichever is greater unless the
procedure is annotated with “Visibility Reduction
by Helicopters NA
.” This annotation means that
there are penetrations of the final approach obstacle
identification surface (OIS) and that the 14 CFR
Section 97.3 visibility reduction rule does not apply
and you must take precaution to avoid any obstacles
in the visual segment. No reduction in MDA/DA is
permitted. The helicopter may initiate the final
approach segment at speeds up to the upper limit of
the highest approach category authorized by the
procedure, but must be slowed to no more than
90 KIAS at the missed approach point (MAP) in
order to apply the visibility reduction. Pilots are
cautioned that such a decelerating approach may
make early identification of wind shear on the
approach path difficult or impossible. If required, use
the Inoperative Components and Visual Aids Table
provided in the front cover of the U.S. Terminal
Procedures Volume to derive the Category A minima
before applying the 14 CFR Section 97.3(d−1) rule.
2.
Helicopters flying Copter SIAPs may use the
published minima, with no reductions allowed. The
maximum airspeed is 90 KIAS on any segment of the
approach or missed approach.
3.
Helicopters flying GPS Copter SIAPs must
limit airspeed to 90 KIAS or less when flying any
segment of the procedure, except speeds must be
limited to no more than 70 KIAS on the final and
missed approach segments. Military GPS Copter
SIAPs are limited to no more than 90 KIAS
throughout the procedure. If annotated, holding may
also be limited to no more than 70 KIAS. Use the
published minima, no reductions allowed.
NOTE
−
Obstruction clearance surfaces are based on the aircraft
speed and have been designed on these approaches for
70 knots. If the helicopter is flown at higher speeds, it may
fly outside of protected airspace. Some helicopters have a
V
MINI
greater than 70 knots; therefore, they cannot meet
the 70 knot limitation to conduct this type of procedure.
Some helicopter autopilots, when used in the “go
−around”
mode, are programmed with a V
YI
greater than 70 knots,
therefore when using the autopilot “go
−around” mode,
they cannot meet the 70 knot limitation to conduct this type
of approach. It may be possible to use the autopilot for the
missed approach in the other than the “go
−around” mode
and meet the 70 knot limitation to conduct this type of
approach. When operating at speeds other than V
YI
or V
Y
,
performance data may not be available in the RFM to
predict compliance with climb gradient requirements.
Pilots may use observed performance in similar
weight/altitude/temperature/speed conditions to evaluate
the suitability of performance. Pilots are cautioned to
monitor climb performance to ensure compliance with
procedure requirements.
4.
TBL 10−1−1 summarizes these require-
ments.
5.
Even with weather conditions reported at or
above landing minima, some combinations of
reduced cockpit cutoff angle, minimal approach/
runway lighting, and high MDA/DH coupled with a
low visibility minima, the pilot may not be able to
identify the required visual reference(s) during the
approach, or those references may only be visible in
a very small portion of the pilot’s available field of
view. Even if identified by the pilot, these visual
references may not support normal maneuvering and
normal rates of descent to landing. The effect of such
a combination may be exacerbated by other
conditions such as rain on the windshield, or
incomplete windshield defogging coverage.
6.
Pilots are cautioned to be prepared to execute
a missed approach even though weather conditions
may be reported at or above landing minima.
NOTE
−
See paragraph 5
−4−21, Missed Approach, for additional
information on missed approach procedures.