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
OAT 6°C
NAV1 108.00 113.00
NAV2 108.00 110.60
134.000 118.000 COM1
123.800 118.000 COM2
WPT _ _ _ _ _ _ DIS _ _ ._ NM DTK _ _ _° TRK 270°
110
80
70
Heading
Lubber line Heading select bug
Course select pointer
Course deviation scale
Course deviation indicator (CDI)
Compass card
Selected heading box
Figure 7-14. An HSI display as seen on the pilot’s primary flight display (PFD) on an electronic flight instrument. Note that only attributes
related to the HSI are labeled.
Chapter 3, Flight Instruments, for operational characteristics.)
[Figure 7-14]
Function of VOR
Orientation
The VOR does not account for the aircraft heading. It only
relays the aircraft direction from the station and will have the
same indications regardless of which way the nose is pointing.
Tune the VOR receiver to the appropriate frequency of the
selected VOR ground station, turn up the audio volume, and
identify the station’s signal audibly. Then, rotate the OBS
to center the CDI needle and read the course under or over
the index.
In Figure 7-12, 360° TO is the course indicated, while in
Figure 7-15, 180° TO is the course. The latter indicates that
the aircraft (which may be heading in any direction) is, at this
moment, located at any point on the 360° radial (line from
the station) except directly over the station or very close to
it, as in Figure 7-15. The CDI will deviate from side to side
as the aircraft passes over or nearly over the station because
of the volume of space above the station where the zone of
confusion exists. This zone of confusion is caused by lack of
adequate signal directly above the station due to the radiation
pattern of the station’s antenna, and because the resultant
of the opposing reference and variable signals is small and
constantly changing.
The CDI in Figure 7-15 indicates 180°, meaning that the
aircraft is on the 180° or the 360° radial of the station. The TO/
FROM indicator resolves the ambiguity. If the TO indicator is
showing, then it is 180° TO the station. The FROM indication
indicates the radial of the station the aircraft is presently on.
Movement of the CDI from center, if it occurs at a relatively
constant rate, indicates the aircraft is moving or drifting off the
180°/360° line. If the movement is rapid or fluctuating, this
is an indication of impending station passage (the aircraft is
near the station). To determine the aircraft’s position relative
to the station, rotate the OBS until FROM appears in the
window, and then center the CDI needle. The index indicates
the VOR radial where the aircraft is located. The inbound (to
the station) course is the reciprocal of the radial.
If the VOR is set to the reciprocal of the intended course,
the CDI will reflect reverse sensing. To correct for needle
deflection, turn away from the needle. To avoid this reverse
sensing situation, set the VOR to agree with the intended
course.
7-13
HDG 215° CRS 180°
VOR
215°
HDG 330° CRS 180°
VOR
330°
VOR
VOR
270° 90°
360° 180°
26 0°
250°
240°
230°
220°
210°
200°
190°
340°
330°
320°
310°
300°
290°
280°
80°
70°
60°
50°
40°
30°
20°
160°
170°
150°
140°
130°
120°
110°
100°
ELECTRONIC FLIGHT
INSTRUMENTS ANALOG SYSTEMS
OBS
N
E
S
W
3
33
24
21
15
12
30
6
FR
OBS
N
E
S
W
3
33
24
21
15
12
30
6
TO
TO
FROM
Figure 7-15. CDI Interpretation. The CDI as typically found on analog systems (right) and as found on electronic flight instruments
(left).
7-14
A single NAVAID will allow a pilot to determine the aircraft’s
position relative to a radial. Indications from a second
NAVAID are needed in order to narrow the aircraft’s position
down to an exact location on this radial.
Tracking TO and FROM the Station
To track to the station, rotate the OBS until TO appears, then
center the CDI. Fly the course indicated by the index. If the CDI
moves off center to the left, follow the needle by correcting
course to the left, beginning with a 20° correction.
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
Instrument Flying Handbook仪表飞行手册下(16)
