12/2/21
AIM
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 at any time. 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 inside the front cover of the U.S. Terminal
Procedures Publication to derive the Category A
minima before applying the 14 CFR Section 97.3
rule.
2.
Helicopters flying Copter IAPs should use
the published minima, with no reductions allowed.
Unless otherwise specified on the instrument
procedure chart, 90 KIAS is the maximum speed on
the approach.
3.
Pilots flying Area Navigation (RNAV)
Copter IAPs should also limit their speed to 90 KIAS
unless otherwise specified on the instrument
procedure chart. The final and missed approach
segment speeds must be limited to no more than 70
KIAS unless otherwise charted. Military RNAV
Copter IAPs are limited to no more than 90 KIAS
throughout the procedure. Use the published minima;
no reductions allowed.
NOTE
−
Obstruction clearance surfaces are based on the aircraft
speed identified on the approach chart and have been
designed on RNAV approaches for 70 knots unless
otherwise indicated. 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 these
RNAV approaches. Some helicopter autopilots, when used
in the “go
−
around” mode, are programmed with a
V
YI
greater than 70 knots. Therefore, those helicopters
when using the autopilot “go
−
around” mode, cannot meet
the 70 knot limitation for the RNAV approach. It may be
possible to use the autopilot for the missed approach in
other than the “go
−
around” mode and meet the 70 knot
limitation. 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.
NOTE
−
V
MINI
−
Instrument flight minimum speed, utilized in
complying with minimum limit speed requirements for
instrument flight
V
YI
−
Instrument climb speed, utilized instead of V
Y
for
compliance with the climb requirements for instrument
flight
V
Y
−
Speed for best rate of climb
4.
TBL 10
−
1
−
1 summarizes these require-
ments.
5.
Even with weather conditions reported at or
above minimums, under some combinations of
reduced cockpit cutoff angle, 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), or those
references may only be visible in a very small portion
of the available field of view. Even if identified by the
pilot, the 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 should always be prepared to execute a
missed approach even though weather conditions
may be reported at or above minimums.
NOTE
−
See paragraph 5
−
4
−
21, Missed Approach, for additional
information on missed approach procedures.
Helicopter IFR Operations
10
−
1
−
3