Abstract : In response to the request of 7 March 1963 from the Director of Defense Research and engineering a radar system is proposed for the primary purpose of surveillance and tracking of aircraft within the USSR and the secondary purpose of detection of missile and ESV launchings. The radar system being proposed is based on the design of the Madre radar and the experience gained with the Madre installation at the NRL Chesapeake Bay Annex. The proposed radar, being required to meet perhaps the most severe demand which could be made of such a high frequency 0TH radar, should have somewhat greater sensitivity, clutter rejection capa- bility and frequency range (6 to 30 Mc) than the NRL Madre. It should also have complete flexibility of operating frequency choice and of antenna scan. These characteristics for the operational radar system are dictated by the combined effect of the information requirements desired and the environment within which the radar must perform, including such factors as the following: