TABLE 3.2. Needs Summary Table – Aircraft Surveillance. Source: OFCM, 2006.


Current Capability

Future Need

Derived aircraft parameters

Aircraft position

Aircraft position, speed, direction, elevation, and type

Vertical Coverage

From 1 km to 60,000 ft.a

From surface to 100,000 ft.

Horizontal Coverage

All U.S. states and territories, including surronding waters and borders.b

Same. Perimeter extends 600 nmi beyond border/coast

Range Resolution

1/8 nmi (1/16 nmi at airports)

Less than 1/8 nmi.


2.2 m2 cross-section (probability of detection >80%)

0.1 m2 cross-section; targets separated by <0.125 nmi reported as separate targets

Scanning Strategy

Repeated base scans every minute; fixed surveillance mode does not allow interrogation of individual objects

Optimize scanning to better cover the lowest 3 km, using negative angles if necessary; agile scanning to interrogate individual objects

Data Latency

120 seconds

<2 seconds

Update Rate

10–12 seconds en route; 4–5 seconds near terminal

<5 seconds



At least as reliable as present units

Dual Polarization

Not available

Should be included in any new system

Radars Networked?


Yes. Data available in common, interoperable formats.

a Lowest 1 km of atmosphere is unsampled by aircraft surveillance radars over 70% of CONUS.

b DOD requires air traffic control radars for global deployment.

c The minimal need is for aircraft surveillance radar data readily shared among FAA, DOD, and DHS.

The radar aircraft surveillance picture is even murkier. The current systems of US civilian aircraft surveillance radars were acquired, and are operated and maintained, by FAA. These radars are used to detect and track aircraft within FAA airspace; they also provide information to the Air Force (DOD/AF) and DHS to facilitate their mission of protecting the U.S. from hostile aircraft. DOD/AF also owns airfield terminal radars and additional surveillance assets for US perimeter protection. Recently, FAA’s mission has been redirected such that FAA is now only responsible for cooperative aircraft; FAA is therefore pursuing the fielding of an independent non-radar system such as the Automatic Dependent Surveillance-Broadcast (ADS-B) (JPDO, 2005) for tracking cooperative aircraft. The current (or any future) radar aircraft surveillance system will then become only a secondary or emergency backup system for FAA. Detection and tracking of non-cooperative aircraft would become a DHS and DOD/AF mission. FAA recently turned over responsibility for the cost of operation and maintenance of the long-range aircraft surveillance radars to DOD/AF and DHS.

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