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
of a screen to the outside which is
marked with compass bearings.
Older equipment will use a cathode
ray tube on which the line appears
(rather like a radar sweep) pointing
to where your transmission is
coming from. More modern digital
equipment uses a circle of LEDs at
10-degree intervals, which will show
the same information, with a digital
readout in the centre. The controller
can store the last transmission, in
case of being busy with something
else at the time. Radar can help by
giving distance information as well.
Accuracy comes in three classes, A,
B or C. Alpha is ± 2°, B is ±°5 and
C is ±10°. You will only be told the
classification if the bearing is B or C.
Radio Procedures
Like aircraft, pilots need radio
licences in order to use the airwaves.
This is normally a separate licence,
which needs you to pass an exam
before it is granted. Although your
use of the airwaves is limited (it's a
subset of the amateur radio
regulations), you still need to know
the phraseology so that other people
don't suffer.
Due to licence restrictions, aircraft
equipment is meant to have as few
controls as possible, including
displays, so some frequencies may
not be completely shown (122.075,
for example, comes up as 122.07).
The Squelch quietens down the
output when no signal is being
received, so you don't get
continuous earfuls of white noise. A
signal coming in cancels this and
activates the audio (a variable squech
merely determines the signal level
when this occurs). The correct
procedure with the Squelch control,
therefore is to rotate the knob until
the hiss just stops, and leave it there,
although it is true to say that this will
hide a weak signal, so lifting the
squelch may help in this case.
Although the phraseology can be a
bit longwinded (day-se-mal for
decimal, for example), and you may
feel a bit stupid pronouncing some
of the words, remember they are
that way to reduce ambiguity.
136 Canadian Private Pilot Studies
Naturally, a continuous listening
watch should be maintained at all
times, as a matter of airmanship, but
especially when transiting controlled
airspace during notified hours of
watch. You must report your
position and height on entering and
just before leaving an ATZ.
There are one or two other points
about radios that aren't often taught
properly during training. The first is
to wait a split second to speak after
pressing the transmit button, which
gives all the relays in the system a
chance to switch over so your
message can get through in full, that
is, not clipping the first bit.
Secondly, whenever you get a
frequency change en route, not only
should you write it down on your
Nav Log, but change to the new
frequency on the other box, so you
alternate between radios. This way,
you have something to go back to if
you can't get through on the new
one for whatever reason (although it
is appreciated that this could create
difficulties with two station boxes
which must be switched every time).
You should use the full callsign on
initial contact with ATC, but you can
subsequently use any abbreviations
they make.
If you need to make a correction, say
the word "Correction" followed by
the last correct word or phrase
before continuing.
Numbers should generally be spoken
individually, except for the words
hundred and thousand where they
occur as round figures. 100, for
example, would be "One Hundred",
but 165 would be "One Six Five".
Usually, with regard to time, you
transmit the numbers relating to
minutes (e.g. "arriving at 45"), but
this only relates to the current hour. If
there is any possibility of confusion,
or you mean another hour, include
the figures.
Standby means "wait to be called".
Affirmative means an agreement, but
the word was changed (at least in
Europe) some time ago, to Affirm, to
reduce the possibilities of it being
confused with negative if only the last
part of the word was heard. In the
same vein, you only use the word
Takeoff when cleared, or cancelling a
takeoff clearance. For an abandoned
takeoff, use the word Stopping.
Roger means that the last message has
been received (even if you didn't
understand it!).
The readability scale is:
1 – unreadable
2 – readable now and then
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
Canadian.Private.Pilot.Studies(87)
