曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
will not be capable of conducting this type of approach.
Similarly, if the autopilot in “go-around” mode climbs
at a VYI greater than 70 knots, then that mode cannot
be used. It is the responsibility of the pilot to determine
compliance with missed approach climb gradient
requirements when operating at speeds other than V Y
or V YI . Missed approaches that specify an “IMMEDI-
ATE CLIMBING TURN” have no provision for a
straight ahead climbing segment before turning. A
straight segment will result in exceeding the protected
airspace limits.
Protected obstacle clearance areas and surfaces for the
missed approach are established on the assumption that
the missed approach is initiated at the DA point and for
nonprecision approaches no lower than the MDA at the
MAP (normally at the threshold of the approach end of
the runway). The pilot must begin the missed approach
at those points! Flying beyond either point before
beginning the missed approach will result in flying
below the protected OCS and can result in a collision
with an obstacle.
The missed approach segment TERPS criteria for all
Copter approaches take advantage of the helicopter’s
climb capabilities at slow airspeeds, resulting in high
climb gradients. [Figure 7-13 on page 7-14] The OCS
used to evaluate the missed approach is a 20:1 inclined
plane. This surface is twice as steep for the helicopter
Figure 7-10. Part 97 Excerpt.
97.3 SYMBOLS AND TERMS USED
IN PROCEDURES
(d) (1) “Copter procedures” means helicopter procedures, with applicable minimums as prescribed
in §97.35 of this part. Helicopters may also use
other procedures prescribed in Subpart C of
this part and may use the Category A minimum
descent altitude (MDA) or decision height
(DH). The required visibility minimum may be
reduced to 1/2 the published visibility minimum, but in no case may it be reduced to less
than one-quarter mile or 1,200 feet RVR.
7-12
Figure 7-11. This COPTER ILS RWY 1 approach chart for Washington/Ronald Reagan National shows the DA for helicopters is 115
feet. The Category II DA for airplanes is 165 feet. The difference is due to the helicopter missed approach obstacle clearance surface (OCS) of 20:1, compared to the 40:1 OCS for airplanes. In this case, the missed approach must be started no later than the
point on the glidepath that the decision height (DH) is reached, in order to miss the Washington Monument.
as the OCS used to evaluate the airplane missed
approach segment. The helicopter climb gradient is
therefore required to be double that of the airplane’s
required missed approach climb gradient.
A minimum climb gradient of at least 400 feet per NM
is required unless a higher gradient is published on the
approach chart; e.g., a helicopter with a ground speed
of 70 knots is required to climb at a rate of 467 feet per
minute (FPM)
2
. The advantage of using the 20:1 OCS
for the helicopter missed approach segment instead of
the 40:1 OCS used for the airplane is that obstacles that
penetrate the 40:1 missed approach segment may not
have to be considered. The result is the DA/MDA may
be lower for helicopters than for other aircraft. The
minimum required climb gradient of 400 feet per NM
for the helicopter in a missed approach will provide 96
feet of required obstacle clearance (ROC) for each NM
of flight path.
Figure 7-12. Indianapolis Heliport Copter GPS 291°.
2
467 FPM = 70 KIAS x 400 feet per NM/60 seconds
7-13
7-14
HELICOPTER APPROACHES
TO VFR HELIPORTS
Helicopter approaches to VFR heliports are normally
developed either as public procedures to a point-inspace (PinS) that may serve more than one heliport or
as a Special procedure to a specific VFR heliport that
requires pilot training due to its unique characteristics.
These approaches can be developed using VOR or
ADF, but RNAV using GPS is the most common system used today. In the future, RNAV using the wide
area augmentation system (WAAS) offers the most
advantages because it can provide lower approach minimums, narrower route widths to support a network of
approaches, and may allow the heliport to be used as an
alternate. A majority of the special procedures to a specific VFR heliport are developed in support of helicop-
ter emergency medical services (HEMS) operators and
have a “Proceed Visually” segment between the MAP
and the heliport. Public procedures are developed as a
PinS approach with a “Proceed VFR” segment between
the MAP and the landing area. These PinS “Proceed
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
Instrument Procedures Handbook (IPH)仪表程序手册下(157)
