AN / APG - 67 The AN / APG - 67 is a multi - mode all - digital X band coherent pulse doppler radar originally developed by General Electric for the Northrop F - 20 Tigershark program of the early 1980s . It offers a variety of air - to - air , air - to - ground , sea - search and mapping modes , and compatibility with most weapons used by the US Air Force in the 1980s . When the F - 20 project ended in the mid - 1980s and no other U . S . sales were immediately forthcoming , GE sold off its radar division . It eventually became part of Lockheed Martin , which sells the APG - 67 for use on light fighter s and trainer aircraft . It has been selected for the AIDC F - CK - 1 Ching - kuo of Taiwan , and the Korean A - 50 attack variant of the T - 50 Golden Eagle , and the latest versions of the FMA IA 63 Pampa , which are built by Lockheed Martin . Description . The APG - 67 is a modern radar featuring a planar phased array antenna and simplified electronics housed in three line - replaceable unit s , one of these being the radar " dish " itself . The entire system weighs less than 160 lb and takes up less than 1 . 9 cubic feet . All communications with the cockpit is handled using the MIL - STD - 1553 data bus ; the data bus allows the data from any of the aircraft ' s sensors to be shown on any of the in - cockpit displays , or sent to other aircraft using a data link . The system broadcasts an average power of 396 watts , allowing it to detect fighter - sized targets at up to 40 nm ( 75 km ) in tracking modes , and up to 80 nm ( 150 km ) in velocity search . In the air - to - air mode it offers long - range velocity search , track - while - scan with up to ten tracked targets , and a variety of single - target - track and auto - lockon " dogfight " modes . It has a variety of pulse repetition frequencies that are automatically selected depending on whether or not the antenna is looking up or down . The APG - 67 also includes a variety of air - to - ground modes including real beam ground mapping , synthetic aperture radar imaging ( SAR ) and beacon tracking . It can also search for moving targets on the ground , and offers tracking modes for ground targets similar to those for air - to - air use . These modes can also be used for sea - surface - search , in which case the display is de - cluttered to remove waves . The SAR mode is an optional add - on to the basic system . History . For many years Northrop had worked with Emerson Electric to provide a series of radars for their F - 5 series . The original F - 5A / B was designed as a light strike aircraft and had only a rudimentary ranging radar for the gunsight , and very little room in the nose for anything else . When the F - 5 airframe was adapted into the F - 5E / F for the air - to - air role , Emerson designed the AN / APQ - 153 to fit into the extremely limited space in the F - 5 ' s nose . The small space and severe weight limitations meant that the APQ - 153 could offer only the most basic features , including basic single - target - track and a scanning mode with a range about 10 nm . A further upgrade produced the AN / APQ - 159 , which offered longer range of about 20 nmi , as well as offering a number of practical improvements like wider scanning angles and improved reliability . When Northrop started work on the latest member of the F - 5 family , then known as the F - 5G , Emerson was initially selected to produce a version of the APQ - 159 with the capability of firing the AIM - 7 Sparrow missile at beyond visual range . However , as the project was repeatedly re - positioned during the late 1970s , Northrop developed the requirement for a much more capable design , able to support both air - to - air and air - to - ground modes like the radars being used in modern designs like the F - 16 Fighting Falcon . Emerson ' s earlier designs were all analog systems so they were not a " shoe in " for the digital system Northrop was looking for , and they threw open the competition to anyone with a suitable design . Several proposals were returned , and General Electric eventually won the contract .