5-2-1 Assignment Criteria
a. General
1. Mode 3/A is designated as the common military/civil mode
for air traffic control use.
2. Make radar beacon code assignments to only Mode 3/A transponder
equipped aircraft.
b. Unless otherwise specified in a directive or a letter of agreement,
make code assignments to departing, en route, and arrival aircraft in accordance
with the procedures specified in this section for the radar beacon code
environment in which you are providing ATC service. Give first preference
to the use of discrete beacon codes.
PHRASEOLOGY -
SQUAWK THREE/ALFA (code),
or
SQUAWK (code).
NOTE -
A code environment is determined by an operating position's/sector's
equipment capability to decode radar beacon targets using either the first
and second or all four digits of a beacon code.
REFERENCE -
FAAO 7110.65, Beacon Identification Methods, paragraph 5-3-3.
a. Issue discrete beacon codes assigned by the computer. Computer
assigned codes may be modified as required.
1. TERMINAL: Aircraft that will remain within the terminal facility's
delegated airspace shall be assigned a code from the code subset allocated
to the terminal facility.
2. TERMINAL: Unless otherwise specified in a Facility Directive
or a Letter of Agreement, aircraft that will enter an adjacent ARTS facility's
delegated airspace shall be assigned a beacon code assigned by the ARTCC
computer.
NOTE -
1 - This will provide the adjacent facility advance information on
the aircraft and will cause autoacquisition of the aircraft prior to handoff.
2 - When an IFR aircraft, or a VFR aircraft that has been assigned
a beacon code by the HOST computer and who's flight plan will terminate
in another facilities area, cancels ATC service or does not activate the
flight plan, send a remove strips (RS) message on that aircraft via HOST
keyboard, the FDIO keyboard, or call via service F.
b. Make handoffs to other positions/sectors on the computer assigned
code.
c. Coastal facilities accepting "over" traffic that will subsequently
be handed off to an oceanic ARTCC shall reassign a new discrete beacon
code to an aircraft when it first enters the receiving facility's airspace.
The code reassignment shall be accomplished by inputting an appropriate
message into the computer and issued to the pilot while operating in the
first sector/position in the receiving facility's airspace.
NOTE -
Per an agreement between FAA and the Department of Defense, 17 code
subsets in the NBCAP have been reserved for exclusive military use outside
NBCAP airspace. To maximize the use of these subsets, they have been allocated
to ARTCCs underlying NBCAP airspace that do not abut an oceanic ARTCC's
area. To preclude a potential situation where two aircraft might be in
the same airspace at the same time on the same discrete code, it is necessary
to reassign an aircraft another code as specified in subparagraph c.
REFERENCE -
FAAO 7110.65, Mixed Environment, paragraph 5-2-4.
FAAO 7110.65, VFR Code Assignments, paragraph 5-2-10.
FAAO 7110.65, Beacon Identification Methods, paragraph 5-3-3.
a. Assign appropriate nondiscrete beacon codes from the function
codes specified in 5-2-6, Function Code Assignments.
b. Unless otherwise coordinated at the time of handoff, make
handoffs to other positions/sectors on an appropriate nondiscrete function
code.
REFERENCE -
FAAO 7110.65, Mixed Environment, paragraph 5-2-4.
FAAO 7110.65, VFR Code Assignments, paragraph 5-2-10.
FAAO 7110.65, Beacon Identification Methods, paragraph 5-3-3.
a. When discrete beacon code capability does not exist in your area of responsibility, comply with the procedures specified in
5-2-3, Nondiscrete Environment.
NOTE -
In a mixed code environment, a situation may exist where a discrete
equipped position/sector exchanges control of aircraft with nondiscrete
equipped facilities or vice versa.
b. When discrete beacon code capability exists in your area of
responsibility:
1. Comply with the procedures specified in 5-2-2, Discrete Environment,
and
2. Unless otherwise coordinated at the time of handoff, assign
aircraft that will enter the area of responsibility of a nondiscrete equipped
position/sector an appropriate nondiscrete function code from the codes
specified in 5-2-6, Function Code Assignments, prior to initiating a handoff.
REFERENCE -
FAAO 7110.65, IFR-VFR and VFR-IFR Flights, paragraph 4-2-8.
FAAO 7110.65, VFR Code Assignments, paragraph 5-2-10.
FAAO 7110.65, Beacon Identification Methods, paragraph 5-3-3.
5-2-5 Radar Beacon Code Changes
Unless otherwise specified in a directive or a letter of agreement or coordinated at the time of handoff, do not request an aircraft to change from the code it was squawking in the transferring facility's area until the aircraft is within your area of responsibility.
REFERENCE -
FAAO 7110.65, IFR-VFR and VFR-IFR Flights, paragraph 4-2-8.
FAAO 7110.65, Beacon Identification Methods, paragraph 5-3-3.
5-2-6 Function Code Assignments
Unless otherwise specified by a directive or a letter of agreement,
make nondiscrete code assignments from the following categories:
a. Assign codes to departing IFR aircraft as follows:
1. Code 2000 to an aircraft which will climb to FL 240 or above
or to an aircraft which will climb to FL 180 or above where the base of
Class A airspace and the base of the operating sector are at FL 180, and
for interfacility handoff the receiving sector is also stratified at FL
180. The en route code shall not be assigned until the aircraft is established
in the high altitude sector.
2. Code 1100 to an aircraft which will remain below FL 240 or
below FL 180 as above.
3. For handoffs from terminal facilities when so specified in
a letter of agreement as follows:
(a) Within NBCAP airspace - Code 0100 to Code 0400 inclusive
or any other code authorized by the regional Air Traffic Division.
(b) Outside NBCAP airspace - Code 1000 or one of the codes
from 0100 to 0700 inclusive or any other code authorized by the regional
Air Traffic Division.
b. Assign codes to en route IFR aircraft as follows:
NOTE -
1 - FL 180 may be used in lieu of FL 240 where the base of Class A
airspace and the base of the operating sector are at FL 180, and for interfacility
handoff the receiving sector is also stratified at FL 180.
2 - The provisions of subparagraphs b2(b) and (c) may be modified by
facility directive or letter of agreement when operational complexities
or simplified sectorization indicate. Letters of agreement are mandatory
when the operating sectors of two facilities are not stratified at identical
levels. The general concept of utilizing Codes 2100 through 2500 within
Class A airspace should be adhered to.
1. Aircraft operating below FL 240 or when control is transferred
to a controller whose area includes the stratum involved.
(a) Code 1000 may be assigned to aircraft changing altitudes.
(b) Code 1100 to an aircraft operating at an assigned
altitude below FL 240. Should an additional code be operationally desirable,
Code 1300 shall be assigned.
2. Aircraft operating at or above FL 240 or when control is
transferred to a controller whose area includes the stratum involved.
(a) Code 2300 may be assigned to aircraft changing altitudes.
(b) Code 2100 to an aircraft operating at an assigned
altitude from FL 240 to FL 330 inclusive. Should an additional code be
operationally desirable, Code 2200 shall be assigned.
(c) Code 2400 to an aircraft operating at an assigned
altitude from FL 350 to FL 600 inclusive. Should an additional code be
operationally desirable, Code 2500 shall be assigned.
3. Code 4000 - When aircraft are operating on a flight plan
specifying frequent or rapid changes in assigned altitude in more than
one stratum or other conditions of flight not compatible with a stratified
code assignment.
NOTE -
1 - Categories of flight that can be assigned code 4000 include certain
flight test aircraft, MTR missions, aerial refueling operation requiring
descent involving more than one stratum, ALTRVs where continuous monitoring
of ATC communications facilities is not required and frequent altitude
changes are approved, and other aircraft operating on flight plans requiring
special handling by ATC.
2 - Military aircraft operating VFR or IFR in restricted/warning areas
or VFR on VR routes will adjust their transponders to reply on Code 4000
unless another code has been assigned by ATC or coordinated, if possible,
with ATC.
c. Assign the following codes to arriving IFR aircraft, except
military turbojet aircraft as specified in 4-7-4, Radio Frequency &
Radar Beacon Changes for Military Aircraft:
NOTE -
FL 180 may be used in lieu of FL 240 where the base of Class A airspace
and the base of the operating sector are at FL 180, and for interfacility
handoff the receiving sector is also stratified at FL 180.
1. Code 2300 may be assigned for descents while above FL 240.
2. Code 1500 may be assigned for descents into and while within
the strata below FL 240, or with prior coordination the specific code utilized
by the destination controller, or the code currently assigned when descent
clearance is issued.
3. The applicable en route code for the holding altitude if
holding is necessary before entering the terminal area and the appropriate
code in subparagraphs c1 or c2.
REFERENCE -
FAAO 7110.65, IFR-VFR and VFR-IFR Flights, paragraph 4-2-8.
FAAO 7110.65, NonDiscrete Environment, paragraph 5-2-3.
FAAO 7110.65, Mixed Environment, paragraph 5-2-4.
FAAO 7110.65, VFR Code Assignments, paragraph 5-2-10.
FAAO 7110.65, Beacon Identification Methods, paragraph 5-3-3.
When the narrowband system is no longer available/usable for ATC purposes, aircraft operating on computer assigned codes shall be instructed to squawk the Function Code appropriate for your area of responsibility.
NOTE -
During the transition to the broadband mode, targets can be maintained
by selecting on the broadband decoder equipment the codes in use by aircraft
in your area or activating the "all" beacon feature.
PHRASEOLOGY -
ALL AIRCRAFT SQUAWK (appropriate code).
REFERENCE -
FAAO 7110.65, Beacon Identification Methods, paragraph 5-3-3.
5-2-8 Emergency Code Assignment
Assign codes to emergency aircraft as follows:
a. Code 7700 when the pilot declares an emergency and the aircraft
is not radar identified.
PHRASEOLOGY -
SQUAWK MAYDAY ON 7700.
b. After radio and radar contact have been established, you may
request other than single piloted helicopters and single piloted turbojet
aircraft to change from Code 7700 to another code appropriate for your
radar beacon code environment.
NOTE -
1 - The code change, based on pilot concurrence, the nature of the
emergency, and current flight conditions will signify to other radar facilities
that the aircraft in distress is identified and under ATC control.
2 - Pilots of single piloted helicopters and single piloted turbojet
aircraft may be unable to reposition transponder controls during the emergency.
PHRASEOLOGY -
RADAR CONTACT (position). IF FEASIBLE, SQUAWK (code).
REFERENCE -
FAAO 7110.65, Beacon Identification Methods, paragraph 5-3-3.
c. The following shall be accomplished on a Mode C equipped VFR
aircraft which is in emergency but no longer requires the assignment of
code 7700:
1. TERMINAL: Assign a beacon code that will permit terminal
minimum safe altitude warning (MSAW) alarm processing.
2. EN ROUTE: An appropriate keyboard entry shall be made to
ensure en route MSAW (EMSAW) alarm processing.
When you observe a Code 7600 display, apply the procedures in paragraph 10-4-4, Communications Failure.
NOTE -
Should a transponder equipped aircraft experience a loss of two-way
radio communications capability, the pilot can be expected to adjust his
transponder to Code 7600.
REFERENCE -
FAAO 7110.65, Beacon Identification Methods, paragraph 5-3-3.
a. For VFR aircraft receiving radar advisories, assign an appropriate Function Code or computer assigned code for the code environment in which you are providing service.
NOTE -
1- Paragraphs 5-2-2, Discrete Environment, 5-2-3, Nondiscrete Environment,
and 5-2-4, Mixed Environment, specify code assignments procedures to follow
for the three code environments.
2 - Paragraph 5-2-6, Function Code Assignments, specifies the Function
Code allocation from which an appropriate code for the aircraft indicated
in subparagraph a should be selected. In the terminal environment, additional
Function Codes may be authorized by the regional Air Traffic division.
1. If the aircraft is outside of your area of responsibility
and an operational benefit will be gained by retaining the aircraft on
your frequency for the purpose of providing services, ensure that coordination
has been effected:
(a) As soon as possible after positive identification,
and
(b) Prior to issuing a control instruction or providing
a service other than a safety alert / traffic advisory.
NOTE -
Safety alerts / traffic advisories may be issued to an aircraft prior
to coordination if an imminent situation may be averted by such action.
Coordination should be effected as soon as possible thereafter.
b. Instruct IFR aircraft which cancel an IFR flight plan and
are not requesting radar advisory service and VFR aircraft for which radar
advisory service is being terminated to squawk the VFR code.
PHRASEOLOGY -
SQUAWK VFR.
or
SQUAWK 1200.
{New-98-3 Added February 26, 1998}
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).
{New-98-3 Revised February 26, 1998}
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.
REFERENCE -
FAAO 7110.66, National Beacon Code Allocation Plan.
c. When an aircraft changes from VFR to IFR, the controller shall
assign a beacon code to Mode C equipped aircraft that will allow MSAW alarms.
REFERENCE -
FAAO 7110.65, Beacon Identification Methods, paragraph 5-3-3.
5-2-11 Beacon Code for Pressure Suit Flights and Flights Above FL 600
a. Mode 3/A, Code 4400, and discrete codes 4401 through 4477 are reserved for use by R-71, F-12, U-2, B-57, pressure suit flights, and aircraft operations above FL 600.
NOTE -
The specific allocation of the special use codes in subset 4400 is
in the NBCAP, FAAO 7110.66.
b. Ensure that aircraft remain on Code 4400 or one of the special
use discrete codes in the 4400 subset if filed as part of the flight plan.
Except when unforeseen events, such as weather deviations, equipment failure,
etc., cause more than one aircraft with same Mode 3/A discrete beacon codes
to be in the same or adjacent ARTCC's airspace at the same time, a controller
may request the pilot to make a code change, squawk standby, or to stop
squawk as appropriate.
NOTE -
Due to the inaccessibility of certain equipment to the flight crews,
Code 4400 or a discrete code from the 4400 subset is preset on the ground
and will be used throughout the flight profile including operations below
FL 600. Controllers should be cognizant that not all aircraft may be able
to accept the transponder changes identified in the Exception. Emergency
code 7700, however, can be activated.
REFERENCE -
FAAO 7110.65, Beacon Identification Methods, paragraph 5-3-3.
5-2-12 Air Defense Exercise Beacon Code Assignment
EN ROUTE
Ensure exercise faker aircraft remain on the exercise flight
plan filed discrete beacon code.
NOTE -
1 - NORAD will ensure exercise faker aircraft flight plans are filed
containing discrete beacon codes from the Department of Defense code allocation
specified in FAAO 7610.4 Appendix 5.
2 - NORAD will ensure that those faker aircraft assigned the same discrete
beacon code are not flight planned in the same or any adjacent ARTCC's
airspace at the same time. (Simultaneous assignment of codes will only
occur when operational requirements necessitate.)
REFERENCE -
FAAO 7110.65, Beacon Identification Methods, paragraph 5-3-3.
5-2-13 Standby or Low Sensitivity Operation
You may instruct an aircraft operating on an assigned code to change transponder to "standby" or "low sensitivity" position:
NOTE -
National standards no longer require improved transponder to be equipped
with the low sensitivity feature. Therefore, aircraft with late model transponders
will be unable to respond to a request to "squawk low."
a. When approximately 15 miles from its destination and you
no longer desire operation of the transponder.
b. When necessary to reduce clutter in a multi-target area,
or to reduce "ring-around" or other phenomena, provided you instruct the
aircraft to return to "normal sensitivity" position as soon as possible
thereafter.
PHRASEOLOGY -
SQUAWK STANDBY,
or
SQUAWK LOW/NORMAL.
REFERENCE -
FAAO 7110.65, Beacon Identification Methods, paragraph 5-3-3.
Continuously monitor the Mode 3/A radar beacon codes assigned for use by aircraft operating within your area of responsibility when nonautomated beacon decoding equipment (e.g., 10-channel decoder) is used to display the target symbol.
REFERENCE -
FAAO 7110.65, Function Code Assignments, paragraph 5-2-6.
NOTE -
In addition to alphanumeric and control symbology processing enhancements,
the ARTS, EARTS, and the TPX-42 systems are equipped with automatic beacon
decoders. Therefore, in facilities where the automatic beacon decoders
are providing the control slash video, there is no requirement to have
the nonautomated decoding equipment operating simultaneously.
REFERENCE -
FAAO 7210.3, Monitoring of Mode 3/A Radar Beacon Codes, paragraph 3-7-4.
{New-98-3 Revised February 26, 1998}
a. This includes the appropriate IFR code actually assigned and,
additionally, code 1200, code 1255, and code 1277 unless your area of responsibility
includes only Class A airspace. During periods when ring-around or excessive
VFR target presentations derogate the separation of IFR traffic, the monitoring
of VFR code 1200, code 1255, and code 1277 may be temporarily discontinued.
b. Positions of operation which contain a restricted or warning
area or VR route within or immediately adjacent to their area of jurisdiction
shall monitor code 4000 and any other code used in lieu of 4000 within
the warning/restricted area or VR route. If by local coordination with
the restricted/warning area or VR route user a code other than 4000 is
to be exclusively used, then this code shall be monitored.
c. If a normally assigned beacon code disappears, check for a
response on the following codes in the order listed and take appropriate
action:
NOTE -
When codes 7500 and/or 7600 have been preselected, it will be necessary
for the ID-SEL-OFF switches for these codes to be left in the OFF position
so that beacon target for an aircraft changing to one of these codes will
disappear, thereby alerting the controller to make the check. This check
will not be required if automatic alerting capability exists.
1. Code 7500 (hijack code).
REFERENCE -
FAAO 7110.65, Hijacked Aircraft, paragraph 10-2-6.
2. Code 7600 (loss of radio communications code).
5-2-15 Failure to Display Assigned Beacon Code or Inoperative/Malfunctioning Transponder
a. Inform an aircraft with an operable transponder that the assigned beacon code is not being displayed.
PHRASEOLOGY -
(Identification) RESET TRANSPONDER, SQUAWK (appropriate code).
b. Inform an aircraft when its transponder appears to be inoperative
or malfunctioning.
PHRASEOLOGY -
(Identification) YOUR TRANSPONDER APPEARS INOPERATIVE/MALFUNCTIONING,
RESET, SQUAWK (appropriate code).
c. Ensure that the subsequent control position in the facility
or the next facility, as applicable, is notified when an aircraft transponder
is malfunctioning/inoperative.
REFERENCE -
FAAO 7110.65, Beacon Identification Methods, paragraph 5-3-3.
5-2-16 Inoperative or Malfunctioning Interrogator
Inform aircraft concerned when the ground interrogator appears to be inoperative or malfunctioning.
PHRASEOLOGY -
(Name of facility or control function) BEACON INTERROGATOR INOPERATIVE/MALFUNCTIONING.
REFERENCE -
FAAO 7110.65, Radar Use, paragraph 5-1-3.
FAAO 7110.65, Beacon Identification Methods, paragraph 5-3-3.
5-2-17 Failed Transponder in Class A Airspace
Disapprove a request or withdraw previously issued approval to operate in Class A airspace with a failed transponder solely on the basis of traffic conditions or other operational factors.
REFERENCE -
FAAO 7110.65, Radar Use, paragraph 5-1-3.
FAAO 7110.65, Beacon Identification Methods, paragraph 5-3-3.
5-2-18 Validation of Mode C Readout
Ensure that Mode C altitude readouts are valid after accepting
an interfacility handoff, initial track start, track start from coast/suspend
tabular list, missing, or unreasonable Mode C readouts. For TPX-42 and
equivalent systems ensure that altitude readout is valid immediately after
identification. (TCDD-/BANS-equipped tower cabs are not required to validate
Mode C readouts after receiving interfacility handoffs from TRACONs according
to the procedures in paragraph 5-4-3, Methods, subparagraph a4.)
a. Consider an altitude readout valid when:
1. It varies less than 300 feet from the pilot reported altitude,
or
PHRASEOLOGY -
SAY ALTITUDE.
2. You receive a continuous readout from an aircraft on the
airport and the readout varies by less than 300 feet from the field elevation,
or
NOTE -
A continuous readout exists only when the altitude filter limits are
set to include the field elevation.
{New-98-3 Revised February 26, 1998}
REFERENCE -
FAAO 7110.65, Altitude Filters, paragraph 5-2-24.
FAAO 7110.65, Selected Altitude Limits, paragraph 5-14-5.
FAAO 7210.3, Display Data, paragraph 11-2-3.
3. You have correlated the altitude information in your data
block with the validated information in a data block generated in another
facility (by verbally coordinating with the other controller) and your
readout is exactly the same as the readout in the other data block.
b. When unable to validate the readout, do not use the Mode C
altitude information for separation.
c. Whenever you observe an invalid Mode C readout below FL 180:
1. Issue the correct altimeter setting and confirm the pilot has accurately reported the altitude.
PHRASEOLOGY -
(location) ALTIMETER (appropriate altimeter), VERIFY ALTITUDE.
2. If the altitude readout continues to be invalid:
(a) Instruct the pilot to turn off the altitude-reporting
part of his/her transponder and include the reason; and,
(b) Notify the operational supervisor-in-charge of the
aircraft call sign.
PHRASEOLOGY -
STOP ALTITUDE SQUAWK. ALTITUDE DIFFERS BY (number of feet) FEET.
d. Whenever you observe an invalid Mode C readout at or above
FL 180, unless the aircraft is descending below Class A airspace:
1. Confirm that the pilot is using 29.92 Hg of mercury as the
altimeter setting and has accurately reported the altitude.
PHRASEOLOGY -
CONFIRM USING TWO NINER NINER TWO AS YOUR ALTIMETER SETTING, VERIFY
ALTITUDE.
2. If the Mode C readout continues to be invalid:
(a) Instruct the pilot to turn off the altitude-reporting
part of his/her transponder and include the reason; and,
(b) Notify the operational supervisor-in-charge
of the aircraft call sign.
PHRASEOLOGY -
STOP ALTITUDE SQUAWK, ALTITUDE DIFFERS BY (number of feet) FEET.
e. Whenever possible, inhibit altitude readouts on all consoles when a malfunction of the ground equipment causes repeated invalid readouts.
5-2-19 Altitude Confirmation - Mode C
Request a pilot to confirm assigned altitude on initial contact unless:
NOTE -
For the purpose of this paragraph, "initial contact" means a pilot's
first radio contact with each sector/position.
a. The pilot states the assigned altitude, or
b. You assign a new altitude to a climbing or a descending aircraft,
or
c. The Mode C readout is valid and indicates that the aircraft
is established at the assigned altitude, or
d. TERMINAL: The aircraft was transferred to you from another
sector/position within your facility (intrafacility).
PHRASEOLOGY -
(In level flight situations), VERIFY AT (altitude).
(In climbing/descending situations), VERIFY ASSIGNED ALTITUDE (altitude).
REFERENCE -
FAAO 7110.65, Beacon Identification Methods, paragraph 5-3-3.
5-2-20 Altitude Confirmation - Non-mode C
a. Request a pilot to confirm assigned altitude on initial contact unless:
NOTE -
For the purpose of this paragraph, "initial contact" means a pilot's
first radio contact with each sector/position.
1. The pilot states the assigned altitude, or
2. You assign a new altitude to a climbing or a descending aircraft,
or
3. TERMINAL: The aircraft was transferred to you from another
sector/position within your facility (intrafacility).
PHRASEOLOGY -
(In level flight situations), VERIFY AT (altitude).
(In climbing/descending situations), VERIFY ASSIGNED ALTITUDE (altitude).
b. USA: Reconfirm all pilot altitude readbacks.
PHRASEOLOGY -
(If the altitude readback is correct), AFFIRMATIVE (altitude).
(If the altitude readback is not correct), NEGATIVE. CLIMB/DESCEND
AND MAINTAIN (altitude),
or
NEGATIVE. MAINTAIN (altitude).
REFERENCE -
FAAO 7110.65, Beacon Identification Methods, paragraph 5-3-3.
5-2-21 Automatic Altitude Reporting
Inform an aircraft when you want it to turn on/off the automatic
altitude reporting feature of its transponder.
PHRASEOLOGY -
SQUAWK ALTITUDE,
or
STOP ALTITUDE SQUAWK.
NOTE -
Controllers should be aware that not all aircraft have a capability
to disengage the altitude squawk independently from the beacon code squawk.
On some aircraft both functions are controlled by the same switch.
REFERENCE -
FAAO 7110.65, Validation of Mode C Readout, paragraph 5-2-18.
FAAO 7110.65, Beacon Identification Methods, paragraph 5-3-3.
P/CG Term Automatic Altitude Report.
5-2-22 In-flight Deviations from Transponder/Mode C Requirements Between 10,000 Feet and 18,000 Feet.
Apply the following procedures to requests to deviate from the Mode C transponder requirement by aircraft operating in the airspace of the 48 contiguous states and the District of Columbia at and above 10,000 feet MSL and below 18,000 feet MSL, excluding the airspace at and below 2,500 feet AGL.
NOTE -
1 - CFR Part 91.215 (b) provides, in part, that all U.S. registered
civil aircraft must be equipped with an operable, coded radar beacon transponder
when operating in the altitude stratum listed above. Such transponders
shall have a Mode 3/A 4096 code capability, replying to Mode 3/A interrogation
with the code specified by ATC, or a Mode S capability, replying to Mode
3/A interrogations with the code specified by ATC. The aircraft must also
be equipped with automatic pressure altitude reporting equipment having
a Mode C capability that automatically replies to Mode C interrogations
by transmitting pressure altitude information in 100-foot increments.
2 - The exception to CFR 91.215(b) is CFR 91.215(b)(5) which states:
except balloons, gliders, and aircraft without engine-driven electrical
systems.
{New-98-3 Revised February 26, 1998}
REFERENCE -
FAAO 7210.3, Temporary Flight Restrictions, Chapter 18, Section
4.
a. Except in an emergency, do not approve inflight requests for
authorization to deviate from CFR Part 91.215(b)(5)(i) requirements originated
by aircraft without transponder equipment installed.
b. Approve or disapprove other in-flight deviation requests,
or withdraw approval previously issued to such flights, solely on the basis
of traffic conditions and other operational factors.
c. Adhere to the following sequence of action when an in-flight
VFR deviation request is received from an aircraft with an inoperative
transponder or Mode C, or is not Mode C equipped:
1. Suggest that the aircraft conduct its flight in airspace unaffected
by the CFRs.
2. Suggest that the aircraft file an IFR flight plan.
3. Suggest that the aircraft provide a VFR route of flight and
maintain radio contact with ATC.
d. Do not approve an in-flight deviation unless the aircraft has
filed an IFR flight plan or a VFR route of flight is provided and radio
contact with ATC is maintained.
e. You may approve an in-flight deviation request which includes
airspace outside your jurisdiction without the prior approval of the adjacent
ATC sector/facility providing a transponder/Mode C status report is forwarded
prior to control transfer.
f. Approve or disapprove in-flight deviation requests within
a reasonable period of time or advise when approval/disapproval can be
expected.
REFERENCE -
FAAO 7110.65, Beacon Identification Methods, paragraph 5-3-3.
Inform an aircraft when you want it to turn off its transponder.
PHRASEOLOGY -
STOP SQUAWK.
For a military aircraft when you do not know if the military service
requires that it continue operating on another mode,
STOP SQUAWK (mode in use).
REFERENCE -
FAAO 7110.65, Beacon Identification Methods, paragraph 5-3-3.
TERMINAL
Set altitude filters to display Mode C altitude readouts to encompass
all altitudes within the controller's jurisdiction. Set the upper limits
no lower than 1,000 feet above the highest altitude for which the controller
is responsible. In those stratified positions, set the lower limit to 1,000
feet or more below the lowest altitude for which the controller is responsible.
When the position's area of responsibility includes down to an airport
field elevation, the facility will normally set the lower altitude filter
limit to encompass the field elevation so that provisions of paragraph
2-1-6, Safety Alert, and paragraph 5-2-18, Validation of Mode C Readout,
subparagraph a2 may be applied. Air Traffic managers may authorize temporary
suspension of this requirement when target clutter is excessive.