AIM

4/3/14

4−1−17

Services Available to Pilots

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

−

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

−

FAAO 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 transpond-

er in the emergency position (Mode A Code 7700 for

civil transponder. Mode 3 Code 7700 and emergency

feature for military transponder.)

11. SQUAWK VFR.

Operate radar beacon

transponder on Code 1200 in the Mode A/3, or other

appropriate VFR code.