| SRAM |
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Model: SRAM.
Short Range Attack Missile Historical Essay © Andreas Parsch Boeing AGM-69 SRAM The SRAM (Short Range Attack Missile) was a relatively small standoff missile for use by USAF's B-52 and FB-111A strategic bombers. On the B-52, it replaced the AGM-28 Hound Dog. After the cancellation of the GAM-87/AGM-48 Skybolt ALBM (Air-Launched Ballistic Missile) in December 1962, the USAF had to find another way to modernize the strike capabilities of its strategic bomber force. In March 1964, SOR (Specific Operational Requirement) 212 for a short-range attack missile was submitted by the USAF, and in March 1965, development was approved by the Department of Defense. SRAM was known as WS (Weapon System) 140A, and the missile designator ZAGM-69A was assigned. The following design competition was won by Boeing, who received a development contract for the SRAM in October 1966. The SRAM was to be used by the B-52, the FB-111A, and the then forthcoming AMSA (Advanced Manned Strategic Aircraft, later designated as B-1). The first powered flight of an AGM-69A occurred in July 1969, and in January 1971, full scale production of the SRAM was approved. In August 1972, the SRAM was operational with SAC units, and quickly replaced the AGM-28 Hound Dog as the B-52's standoff attack missile. The AGM-69A was a ballistic-type air-to-ground missile powered by a Lockheed SR75-LP-1 two-stage solid-fuel rocket motor, and armed with a 200 kT W-69 thermonuclear warhead. The first motor stage propelled the missile to Mach 3 after launch, and the second stage was ignited near the target for a powered terminal approach. Maximum range varied from 55 km (35 miles) for low-altitude launches to 160 km (100 miles) for high-altitude firings. The SRAM was guided by an General Precision/Kearfott KT-76 inertial navigation system, assisted by a Stewart-Warner terrain clearance sensor, and could achieve an accuracy of about 430 m (1400 ft) CEP. The B-52 Stratofortress could carry 8 SRAMs on a rotary launcher in the bomb bay, and up to 12 more on two external 6-missile pylons. The FB-111A could carry up to 6 SRAMs. When carried externally, an expendable tail faring was used on the missile to reduce drag. The AGM-69A greatly increased the number of targets which could be attacked by a single bomber, and made it possible to attack known (fixed) air-defense installations en route to the primary target. Several proposals were made to improve the versatility of the AGM-69A, including a radar guidance system to use it as an air-to-air missile, or an anti-radiation seeker to attack mobile air-defense radars, but none of these features were adopted. In the mid-1970s, however, storability problems with the rocket motor surfaced, and in 1976 Thiokol was awarded a contract to develop a new motor for SRAM. In 1977, the new motor was combined with other upgrades, including an improved guidance system (with enhanced computing capability) and the W-80 warhead of the AGM-86 ALCM. The new SRAM missile, designated AGM-69B SRAM B, was intended for use by the B-1A. In 1978, however, the B-1A was cancelled, and the USAF found a way to extend the lifespan of the old motor to the originally planned 5 years, and these two events killed the AGM-69B program. Instead, it was then planned to eventually replace the AGM-69A with the AGM-86 ALCM and the forthcoming ASALM (Advanced Strategic Air-Launched Missile). The latter, however, was also cancelled in 1980. When the B-1 program was resurrected (as B-1B) in 1981, it was decided to develop an entirely new weapon, later to be known as AGM-131 SRAM II. In June 1990, the AGM-69A SRAM was retired from the USAF inventory. Various reasons have been quoted, including unreliability of the warhead and the rocket motor. The AGM-131 SRAM II was cancelled the following year, leaving effectively a gap in the capability of the USAF's B-52 bomber force. A total of about 1500 AGM-69A missiles were built by Boeing until production ended in 1975. SpecificationsNote: Data given by several sources show slight variations. Figures given below may therefore be inaccurate! Data for AGM-69A:
[1] James N. Gibson: "Nuclear Weapons of the United States", Schiffer Publishing Ltd, 1996 Manufacturer: Boeing. Launches: 31. Failures: 1. Success Rate: 96.77%. First Launch Date: 1974-08-20. Last Launch Date: 1983-07-26. Launch data is: complete. Apogee: 10 km (6 mi). Liftoff Thrust: 0 N ( lbf). Total Mass: 1,016 kg (2,239 lb). Core Diameter: 0.45 m (1.47 ft). Total Length: 4.82 m (15.81 ft). Span: 0.61 m (2.00 ft). Maximum range: 190 km (110 mi). Number Standard Warheads: 1. Standard warhead: W69. Standard warhead yield: 170 KT. Boost Propulsion: Solid rocket. Guidance: Inertial. Maximum speed: 3,710 kph (2,300 mph). Development Cost $: 450.600 million. in: 1974 average dollars. Recurring Price $: 0.466 million. Total Number Built: 1541. Total Development Built: 41. Total Production Built: 1500. Flyaway Unit Cost $: 0.267 million. in: 1974 unit dollars.
Model: SRAM-2.
Short Range Attack Missile Historical Essay © Andreas Parsch Boeing AGM-131 SRAM II The SRAM II (Short-Range Attack Missile) was intended as a replacement for the AGM-69 SRAM, but it was not produced in quantity. In 1977, the USAF planned to develop an upgrade of the SRAM for the forthcoming B-1A bomber as AGM-69B SRAM B. When the B-1A was cancelled in 1978, the AGM-69B was dropped, too. After the resurrection of the B-1 program (as B-1B) in 1981, it was decided to develop an entirely new weapon, the SRAM II. In 1986, Boeing was finally awarded a development contract for the AGM-131A SRAM II. The AGM-131A was planned to have only about 2/3 the size of an AGM-69A, so that 36 missiles could be carried by the B-1B, as compared to 24 AGM-69As. One new feature of SRAM II was a lighter, simpler, and more reliable rocket motor by Thiokol for increased range. The SRAM II also used a new W-89 thermonuclear warhead, which was much safer to operate than the W-69 of the AGM-69. Initial Operational Capability for the AGM-131A was planned for 1993, but after flight tests in the late 1980s, the program was cancelled in 1991. Stated reasons include technical (difficulties with the rocket motor) and political (nuclear arms reduction) ones. The AGM-131B SRAM-T (SRAM-Tactical) was a version intended for use by the F-15E Eagle tactical strike aircraft. The SRAM-T reached the flight-test stage, but was eventually cancelled, too. SpecificationsNote: Data given by several sources show slight variations. Figures given below may therefore be inaccurate! Data for AGM-131A (except where noted):
[1] James N. Gibson: "Nuclear Weapons of the United States", Schiffer Publishing Ltd, 1996 Total Mass: 877 kg (1,933 lb). Core Diameter: 0.40 m (1.31 ft). Total Length: 4.27 m (14.00 ft). Span: 0.61 m (2.00 ft). Maximum range: 390 km (240 mi). Number Standard Warheads: 1. Boost Propulsion: Solid rocket. Guidance: Inertial. SRAM Chronology 1974 August 20 - 11:09 GMT - Grand Turk Island DZ -. FAILURE: Failure. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1975 March 25 - 12:01 GMT - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1975 April 21 - 12:35 GMT - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1975 May 12 - 11:24 GMT - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1975 May 12 - 11:54 GMT - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1975 May 23 - 11:35 GMT - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1975 May 23 - 11:58 GMT - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1975 November 13 - 13:16 GMT - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1975 November 14 - 12:30 GMT - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1975 November 24 - 13:15 GMT - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1976 April 14 - 12:01 GMT - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1976 April 14 - 12:21 GMT - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1976 December 14 - 12:00 GMT - Grand Turk Island DZ -. Test mission Agency: USAF SAC. Apogee: 10 km (6 mi). 1976 December 14 - 12:20 GMT - Grand Turk Island DZ -. Test mission Agency: USAF SAC. Apogee: 10 km (6 mi). 1977 April 14 - 11:59 GMT - Grand Turk Island DZ -. SRAM Case 29 Test mission Agency: USAF SAC. Apogee: 10 km (6 mi). 1977 December 14 - 12:54 GMT - Grand Turk Island DZ -. SRAM Case 33 Test mission Agency: USAF SAC. Apogee: 10 km (6 mi). 1978 March 1 - 12:00 GMT - Grand Turk Island DZ -. SRAM Case 34 Test mission Agency: USAF. Apogee: 10 km (6 mi). 1978 July 20 - 11:49 GMT - Grand Turk Island DZ -. SRAM Case 30 Test mission Agency: USAF. Apogee: 10 km (6 mi). 1978 December 13 - 11:58 GMT - Grand Turk Island DZ -. SRAM Case 33 Test mission Agency: USAF. Apogee: 10 km (6 mi). 1979 January 17 - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1979 January 19 - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1979 January 19 - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1979 February 7 - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1979 November 28 - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1979 December 12 - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1979 December 12 - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1980 February 6 - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1980 November 5 - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1981 December 9 - Grand Turk Island DZ -. SRAM Case 85 Test mission Agency: USAF. Apogee: 10 km (6 mi). 1983 June 22 - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi). 1983 July 26 - Grand Turk Island DZ -. Test mission Agency: USAF. Apogee: 10 km (6 mi).
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