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Show Aviaticn & Technology 2 Sept Athena Rocket Launches to Begin In Air Force Re-entry Research Washington-First of 77 Athena rockets is scheduled to be launched next month at White Sands Missile Range, N. M., in Air Force's advanced ballistic re-entry systems (ABRES) program, which is designed to provide trajectory dynamics data on a wide variety of missile re-entry bodies and penetration aids. The program is part of USAF's 627A re-entry research effort which also includes 20-30 flights of General Dynamics Atlas F missiles carrying payloads of new materials, maneuverable nose cones and decoys and other penetration aids (AW Dec. 10, p. 27). The Atlas flights are being conducted from Atlantic and Pacific missile ranges. ""*"" Phase 1 of the Athena rocket portion of the program was completed last month. It involved launch of 15 Nike-Apache sounding rockets from White Sands and Wallops Island, Va., to check ground and flight instrumentation. Phase 2 of the rocket program could be expanded beyond the 77 launches now scheduled. Total program cost through the firm schedule is $40 million. Plan is to launch payloads ranging in weight from 50-300 lb. to altitudes up to 500,000 ft. and then to drive them downward into the atmosphere at reentry velocities up to 23,000 fps. Design payload weighs 50 lb., and design re-entry altitude is 250,000 ft. Re-entry angles will be varied from 18-45 deg. Athena Integration The Athena rocket is being integrated by Atlantic Research Corp., which also is test conductor and facilities contractor for this phase of ABRES. The four-stage Athena has these characteristics: • First stage, consisting of a Thiokol XM33-E8 Castor augmented by two Thiokol XM19-E1 Recruits. Castor has a 54,000 lb. thrust and 40 sec. burning time. Thrust of the Recruits is 34,000 lb., and they burn for 2.3 sec. • Second stage will come in two configurations. For low-angle re-entries, a Thiokol TX261-2, with a 63,000 lb. thrust and 13 sec. burning time will be used. In high-angle re-entry missions, the stage will be a Hercules-Allegany Ballistic Laboratory X259-A4, which produces 21,000 lb. and has a 35 sec. burning time. • Velocity package has an Aerojet 8,000 lb. thrust, 30-sec. burn motor as the third stage. The fourth stage is an ABL Ranger motor, which produces 5,000 lb. thrust and burns 9.5 sec. Also in the velocity package are the payload, attitude control and telemetry systems. In a typical mission, the velocity package will be carried to altitude by the first two stages, which are un-guided and fin-stabilized. The fins are canted to impart a spin. The velocity package is ejected while the vehicle is coasting to apogee. It is de-spun by means of a yo-yo device, pitches over and is oriented by means of a cold gas jet attitude control system. After burnout of the third and fourth stage motors, the re-entry shape and warhead decoys are ejected and reach maximum velocity at about 250,000 ft. altitude. The payload is contained in an envelope 25 in. in dia. and 72 in. long. The four-stage, all-solid propellant Athena vehicle is 50 ft. long and has a pad weight of 15,750 lb. Two Pads Planned Two pads, with -rail launchers, will be employed for the Athena launches. They are located near Green River, Utah, about 470 mi. from the impact point at White Sands. FPS-16 radars will position track the vehicle during first and second stage burning and the launch site will be equipped with destruct command capability because the vehicle flies over some sparsely-populated areas. Air Force has modified K, C and X-band radars for re-entry signature measurements. These measurements also will be made in UHF, VHF, L and S bands. A 24-megawatt S-band Rampart radar and a 30-megawatt combination L/UHF radar will be used for frontal viewing and are located at the southeast corner of the impact range. A similar radar combination will be used for side viewing from the northwest corner. Other ground stations will make measurements in the visible and infrared frequencies. An instrumented Boeing KC-135 aircraft, flying along the payload trajectory, will measure payload signatures in visible, ultraviolet and infrared frequencies. Athena fundamentally is an outgrowth of National Aeronautics and Space Administration's Trailblazer reentry research rocket program, which utilized a spherical rocket as both fourthy stage and payload to study re-entry de tection, tracking, communications and nose cone materials (AW Jan. 16, w61, p. 102). Trailblazer 2 had the/same booster stage as Athena. It also was engineered and fabricated by Atlantic Research Corp. The Athena program is being directed by the Ballistic Systems Div. of Air Force Systems Command, through BSD's Ballistic Missile Re-entry Systems Office. ARC's Space Vehicles Div., El Monte, CalU ~**ui\\ conduct the tests, which will use payloads provided by a large number of industry contractors. Others in the management structure are Aerospace Corp., systems engineering; Lincoln Laboratories of Massachusetts Institute of Technology, consultation; Navy and Advanced Research Projects Agency, several experimental payloads; Army, range support, and Systems Command's Electronics Systems Div., range instrumentation. |
