AIM
8/15/19
4
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1
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17
Services Available to Pilots
(d)
Within 10 miles of certain designated
airports, excluding that airspace which is both outside
the Class D surface area and below 1,200 feet AGL.
Balloons, gliders and aircraft not equipped with an
engine driven electrical system are excepted from this
requirement.
3.
14 CFR Section 99.13 requires all aircraft
flying into, within, or across the contiguous U.S.
ADIZ be equipped with a Mode C or Mode S
transponder. Balloons, gliders and aircraft not
equipped with an engine driven electrical system are
excepted from this requirement.
4.
Pilots must ensure that their aircraft transpon-
der is operating on an appropriate ATC assigned
VFR/IFR code and Mode C when operating in such
airspace. If in doubt about the operational status of
either feature of your transponder while airborne,
contact the nearest ATC facility or FSS and they will
advise you what facility you should contact for
determining the status of your equipment.
5.
In-flight requests for “immediate” deviation
from the transponder requirement may be approved
by controllers only when the flight will continue IFR
or when weather conditions prevent VFR descent and
continued VFR flight in airspace not affected by the
CFRs. All other requests for deviation should be
made by contacting the nearest Flight Service or
Air Traffic facility in person or by telephone. The
nearest ARTCC will normally be the controlling
agency and is responsible for coordinating requests
involving deviations in other ARTCC areas.
g. Transponder Operation Under Visual Flight
Rules (VFR)
1.
Unless otherwise instructed by an ATC
facility, adjust transponder to reply on Mode 3/A
Code 1200 regardless of altitude.
NOTE
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1.
Aircraft not in contact with an ATC facility may squawk
1255 in lieu of 1200 while en route to, from, or within the
designated fire fighting area(s).
2.
VFR aircraft which fly authorized SAR missions for the
USAF or USCG may be advised to squawk 1277 in lieu of
1200 while en route to, from, or within the designated
search area.
3.
Gliders not in contact with an ATC facility should
squawk 1202 in lieu of 1200.
REFERENCE
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FAA Order JO 7110.66, National Beacon Code Allocation Plan
.
2.
Adjust transponder to reply on Mode C, with
altitude reporting
capability activated
if the aircraft is
so equipped, unless deactivation is directed by ATC
or unless the installed equipment has not been tested
and calibrated as required by 14 CFR Section 91.217.
If deactivation is required and your transponder is so
designed, turn off the altitude reporting switch and
continue to transmit Mode C framing pulses. If this
capability does not exist, turn off Mode C.
h. Radar Beacon Phraseology
Air traffic controllers, both civil and military, will use
the following phraseology when referring to
operation of the Air Traffic Control Radar Beacon
System (ATCRBS). Instructions by ATC refer only to
Mode A/3 or Mode C operation and do not affect the
operation of the transponder on other Modes.
1. SQUAWK (number).
Operate radar beacon
transponder on designated code in Mode A/3.
2. IDENT.
Engage the “IDENT” feature (mili-
tary I/P) of the transponder.
3. SQUAWK (number) and IDENT.
Operate
transponder on specified code in Mode A/3 and
engage the “IDENT” (military I/P) feature.
4. SQUAWK STANDBY.
Switch transponder
to standby position.
5. SQUAWK LOW/NORMAL.
Operate
transponder on low or normal sensitivity as specified.
Transponder is operated in “NORMAL” position
unless ATC specifies “LOW” (“ON” is used instead
of “NORMAL” as a master control label on some
types of transponders.)
6. SQUAWK ALTITUDE.
Activate Mode C
with automatic altitude reporting.
7. STOP ALTITUDE SQUAWK.
Turn off
altitude reporting switch and continue transmitting
Mode C framing pulses. If your equipment does not
have this capability, turn off Mode C.
8. STOP SQUAWK (mode in use).
Switch off
specified mode. (Used for military aircraft when the
controller is unaware of military service require-
ments for the aircraft to continue operation on another
Mode.)
9. STOP SQUAWK.
Switch off transponder.
10. SQUAWK MAYDAY.
Operate transpon-
der in the emergency position (Mode A Code 7700 for
civil transponder. Mode 3 Code 7700 and emergency
feature for military transponder.)