AIM Text
- ASDE-X/ASSC is a multi-sensor surface surveillance system the FAA has acquired for airports in the United States. This system provides high resolution, short-range, clutter free surveillance information about aircraft and vehicles, both moving and fixed, located on or near the surface of the airport's runways and taxiways under all weather and visibility conditions. The system consists of:
- A Primary Radar System. ASDE-X/ASSC system coverage includes the airport surface and the airspace up to 200 feet above the surface. Typically located on the control tower or other strategic location on the airport, the Primary Radar antenna is able to detect and display aircraft that are not equipped with or have malfunctioning transponders or ADS-B.
- Interfaces. ASDE-X/ASSC contains an automation interface for flight identification via all automation platforms and interfaces with the terminal radar for position information.
- Automation. A Multi-sensor Data Processor (MSDP) combines all sensor reports into a single target which is displayed to the air traffic controller.
- Air Traffic Control Tower Display. A high resolution, color monitor in the control tower cab provides controllers with a seamless picture of airport operations on the airport surface.
- The combination of data collected from the multiple sensors ensures that the most accurate information about aircraft location is received in the tower, thereby increasing surface safety and efficiency.
- The following facilities are operational with ASDE-X:
TBL 4-5-1
BWI
Baltimore Washington International
BOS
Boston Logan International
BDL
Bradley International
MDW
Chicago Midway
ORD
Chicago O'Hare International
CLT
Charlotte Douglas International
DFW
Dallas/Fort Worth International
DEN
Denver International
DTW
Detroit Metro Wayne County
FLL
Fort Lauderdale/Hollywood Intl
MKE
General Mitchell International
IAH
George Bush International
ATL
Hartsfield-Jackson Atlanta Intl
HNL
Honolulu International
JFK
John F. Kennedy International
SNA
John Wayne-Orange County
LGA
LaGuardia
STL
Lambert St. Louis International
LAS
Las Vegas Harry Reid International
LAX
Los Angeles International
SDF
Louisville International
MEM
Memphis International
MIA
Miami International
MSP
Minneapolis St. Paul International
EWR
Newark International
MCO
Orlando International
PHL
Philadelphia International
PHX
Phoenix Sky Harbor International
DCA
Ronald Reagan Washington National
SAN
San Diego International
SLC
Salt Lake City International
SEA
Seattle-Tacoma International
PVD
Theodore Francis Green State
IAD
Washington Dulles International
HOU
William P. Hobby International
- The following facilities have been projected to receive ASSC:
TBL 4-5-2
SFO
San Francisco International
CLE
Cleveland-Hopkins International
MCI
Kansas City International
CVG
Cincinnati/Northern Kentucky Intl
PDX
Portland International
MSY
Louis Armstrong New Orleans Intl
PIT
Pittsburgh International
ANC
Ted Stevens Anchorage International
ADW
Joint Base Andrews AFB
Source: FAA Aeronautical Information Manual · current edition · paragraph 4-5-5.
Research Notes
AIM 4-5-5 covers Transponder Operation — operational use of the transponder during all phases of flight.
When the transponder must be ON: Per § 91.215, when operating in airspace requiring transponder use. This includes Class A, B, C, Mode C veil, and above 10,000 MSL (with the 2,500 AGL exception). VFR operations in uncontrolled airspace don't strictly require transponder operation, but most pilots leave it on for visibility to ATC and to other aircraft (via TCAS).
Standard VFR squawk codes:
- 1200 — default VFR (use unless ATC assigns different code)
- 0000 — used by military / federal aircraft for specific operations
Emergency codes:
- 7500 — hijack/unlawful interference
- 7600 — radio comms failure
- 7700 — general emergency
When ATC assigns a discrete code: Squawk it. Maintain on that code until ATC changes it or until ATC says "squawk VFR" (which means revert to 1200).
The 'ident' function: Press the IDENT button when ATC requests "squawk [code] and ident." The button triggers a special radar return that ATC can see — confirming aircraft identity. Don't press it spontaneously.
Reference: § 91.215; § 91.225 (ADS-B); AIM 4-1-20; AIM 4-5-5.