In 1985, an ailing solar observation satellite in orbit over 300 miles above the Earth was the target of a United States Air Force F-15A armed with a 2,700 lb missile in an attempt to test the ability to destroy Soviet satellites during the Cold War.
The Threat
Beginning in the early 1960s, shortly after the downing of the United States’ Lockheed U-2 spy plane on May 1, 1960, the Soviets next looked to neutralize American spy satellites orbiting out of reach of their surface-to-air systems.
A program was initiated by Soviet leader Nikita Khrushchev to design and construct a weapon to destroy satellites. The weapon was known as Istrebitel Sputnikov (Satellite Destroyer). The spacecraft would be launched into space and guided by a complex network of tracking stations and command posts, maneuvered to its target, closing the proximity to it, and detonated, destroying the enemy satellite with shrapnel.
The first flight test was in 1963, with the system’s first intercept in space of a specially designed target satellite occurring on Nov. 1, 1968. By 1978 the system had been perfected to the point of being able to launch the Istrebitel Sputnikov in less than two hours atop a Soviet ICBM (Intercontinental Ballistic Missile). America’s main source of intelligence gathering, spy satellites, was now threatened by this new form of weapon known as ASAT (Anti-Satellite).
The Response — the ASM-135 ASAT
The United States had been developing ASAT weapons as well beginning in the late 1950s, some of them nuclear armed. The issue with nuclear armed anti-satellite weapons is they would not only disable the target, but friendly satellites as well. In 1978 President Jimmy Carter directed the United States Air Force (USAF) to develop a new anti-satellite weapon system.
In the same year, the U.S. Air Force issued a requirement for an air-launched missile utilizing an Air-Launched Miniature Vehicle (ALMV), also known as a Miniature Homing Vehicle (MHV), for use against satellites in low-earth orbit. LTV Aerospace (Ling-Temco-Vought) developed a design that featured a multi-stage missile designed to be launched from an F-15A interceptor in a supersonic zoom climb at high altitudes. Two solid stages would propel the missile into space, the second one pointing the MHV towards the target in order that the infrared image of the satellite could be detected by the MHV. The MHV, upon separation, would be spin-stabilized by using 63 short-pulsed rocket motors for maneuvering. The MHV would then destroy the target by striking it at a speed of at least 15,000 mph.
Flight tests with the ASM-135 began in 1982 with captive carry (not launched) flights by an F-15A aircraft at Edwards Air Force Base, California. On Jan. 21, 1984, Maj. Ralph B. Filburn, flying a McDonnell Douglas F-15A (76-0086), successfully launched an ASM-135A using a point in space as a reference. In 1985 President Ronald Reagan authorized a test against a satellite.
The Test
Flying at an altitude of 345 miles, the ailing Solwind P78-1 solar observation satellite was the chosen target. Piloting the “Celestial Eagle” F-15A (76-0084), Maj. Wilbert D. “Doug” Pearson would take-off from Edwards Air Force Base on Sept. 13, 1985, with an ASM-135 attached to his aircraft centerline. Flying at Mach 1.22, Pearson executed a zoom climb at an angle of 65 degrees, and the ASM-135 automatically launched at 38,100 ft at a predetermined point, while the F-15A was flying at Mach .934 or 616.5 mph. The 30 lb MHV slammed into the 2,000 lb satellite at a closing speed of 15,000 mph, destroying ot. It was the first and only time a satellite was destroyed by a U.S. missile.
Pearson would not be able to see his target or if it was destroyed, but through a series of coded radio transmissions the results were to be communicated with him. However, all that was required was yelling and cheering in the background coming over his radio when the mic was keyed on the other side to inform him it was a success. In August and September of 1986, two further tests targeted stars, the MHV being successfully directed to the respective points in space.
The ASM-135 was 17 ft 9.5 in in length with a diameter of 20 inches, and weighed in between 2,600 and 2,700 lb. It had a ceiling of at least 350 miles, possibly to over 600 miles.
The F-15A was powered by two Pratt & Whitney F100-PW-100 turbofan engines generating 25,000 lbs of thrust each. Maximum speed of the aircraft is Mach 2.5. Able to carry four AIM-7 Sparrow and four AIM-9 Sidewinder missiles, it also was normally armed with a 20 mm M61A1 Vulcan cannon, and could carry up to 15,000 lbs of external ordinance. The F-15s used to test the ASM-135 had special equipment installed in place of the gun’s ammunition drum, along with other modifications.
The Aftermath
In the 1980s there were rising concerns about the weaponization of space, the Soviets had killer satellites and President Reagan was talking about the Strategic Defense Initiative (SDI), which became better known as “Star Wars.”
“Killer weapons in space” became a concern as well as space debris created by this type of warfare, and this led to congress banning the testing of the missile on targets in space in December 1985. Despite the plans the U.S. Air Force had to modify 20 F-15A aircraft to carry the ASM-135 and for a force of 112 operational missiles to be produced, the program was cancelled in 1988. A total of 15 ASM-135 were produced with 5 being flight tested. There are captive versions of the missile, CASM-135, on display at the National Museum of the United States Air Force in Dayton, Ohio, and one at the Smithsonian Steven F. Udvar-Hazy Center in Chantilly, VA. The later also includes a cutaway model of the MHV.
F-15A 76-0084 “Celestial Eagle”
The history of the F-15A flown that day by Maj. Pearson was discovered almost 22 years later by Staff Sgt. Aaron Hartley, a crew chief and aviation history buff assigned to the Florida Air National Guard 125th Fighter Wing, Detachment 1. Hartley was researching the history of the F-15s assigned to his unit, when he learned that their F-15A 76-0084 had flown the ASAT mission. He reached out via email to the retired Major General Pearson.
Pearson mentioned he’d like to fly the aircraft once again, and also his son, Todd Pearson, was a Captain and an F-15 pilot based at Mountain Home AFB, Idaho. The idea of a Celestial Eagle remembrance flight was born. 22 years to the exact date, on Sept. 13, 2007, wearing the same circular patch on his shoulder as his father, Capt. Pearson sat in the cockpit of the same F-15A his father had flown. “Celestial Eagle” had been painted on the nose, and the Captain’s name placed on the outside of the cockpit. General Pearson was also on hand along with family.
In 2009, F-15A number 76-0084 was retired and placed in storage at Davis-Monthan AFB in Tucson, AZ, in 2010. Now a member of the “Boneyard”, another historic aircraft awaits its fate.
