AIM ¶ 4-5-5 — ASDE-X/ASSC Surface Surveillance
AIM 4-5-5 explains ASDE-X and ASSC airport surface detection systems, sensors, coverage, and tower displays used to enhance runway and taxiway safety.
In Plain English
ASDE-X (Airport Surface Detection Equipment, Model X) and ASSC (Airport Surface Surveillance Capability) are multi-sensor surveillance systems that give tower controllers a clear picture of aircraft and vehicles on or near runways and taxiways — even in low visibility or bad weather. This dramatically reduces the risk of runway incursions and surface conflicts.
Key components include:
- Primary Radar System: Mounted on the tower or other strategic location, it covers the airport surface and airspace up to 200 feet AGL. It can detect aircraft without working transponders or ADS-B.
- Interfaces: Tie-ins with automation platforms (for flight ID) and the terminal radar (for position).
- Multi-sensor Data Processor (MSDP): Fuses all sensor inputs into a single target symbol.
- Tower Display: A high-resolution color monitor in the cab gives controllers a seamless view of surface operations.
Why it matters to you as a pilot: at ASDE-X/ASSC airports (major hubs like ATL, ORD, JFK, LAX, DFW), controllers see your aircraft on the surface in real time. Expect tighter taxi instructions, prompt hold-short reminders, and quicker conflict alerts. Always read back hold-short clearances precisely — the system helps controllers catch errors fast.
AIM Source Text
FAA AIM ¶ 4-5-54-5-5. 4-5-5. Airport Surface Detection Equipment (ASDE-X)/Airport Surface Surveillance Capability (ASSC)
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
Oral Exam Questions a DPE Might Ask
Q1What is ASDE-X/ASSC and what is its purpose?
Per AIM 4-5-5, ASDE-X/ASSC is a multi-sensor airport surface surveillance system that provides high-resolution, clutter-free information about aircraft and vehicles on or near runways and taxiways under all weather and visibility conditions, enhancing surface safety and efficiency.
Q2What is the coverage volume of the ASDE-X/ASSC primary radar?
Per AIM 4-5-5, the system covers the airport surface and the airspace up to 200 feet above the surface, and it can detect aircraft that are not equipped with or have malfunctioning transponders or ADS-B.
Q3What are the main components of an ASDE-X/ASSC system?
Per AIM 4-5-5, the system consists of a Primary Radar System, automation interfaces (for flight identification and terminal radar position data), a Multi-sensor Data Processor (MSDP) that fuses sensor reports into a single target, and a high-resolution color tower cab display.
Related Paragraphs in AIM Chapter 4