ASM-135: The Only Time a Fighter Shot Down a Satellite

por | Sep 7, 2026 | Historia y leyendas, Aviación militar | 0 comentarios

The thing hanging under the F-15 was not a bomb. It was a two-stage rocket seventeen feet ten inches long, and inside its nose sat an object the size of a large coffee can that weighed thirty pounds, carried no explosive of any kind, and had no engine capable of pushing it forward.

All it could do was point itself. The plan was to put it directly in the path of a satellite moving at seventeen thousand miles an hour and let physics do the rest.

On 13 September 1985 it worked, and it has never been attempted from an aircraft again.

Quick Facts — ASM-135 ASAT

Fecha: 13 September 1985, impact at 20:43 GMT

Piloto: Maj. Wilbert D. “Doug” Pearson Jr., USAF, callsign Aggie-1

Aeronave: F-15A 76-0084, from Edwards AFB, carrying the missile on the centreline

Misil: Vought ASM-135A — 17 ft 10 in, about 2,600–2,700 lb

Stage 1: Modified Boeing AGM-69 SRAM airframe, Lockheed two-pulse solid motor

Stage 2: Vought Altair III with a Thiokol FW-4S motor

Cabeza armada: None. A 30 lb Miniature Homing Vehicle, hit-to-kill

Objetivo: Solwind P78-1, launched 24 February 1979

Launch conditions: Mach 1.22, 3.8 g into a 65° climb, release at 38,100 ft at Mach 0.934

Debris created: 285 catalogued fragments, the last of which decayed in May 2004

Tests flown: Five, of which one was against a satellite

Programa cancelado: 1988

A Coffee Can That Could Only Point

The Miniature Homing Vehicle is the reason this story is interesting, and it is worth understanding what it actually was, because it was not a missile in any sense a pilot would recognise.

It had no forward propulsion. It had fifty-six full-charge divert motors and eight half-charge end-game motors arranged around its circumference, plus four attitude-control pods at the back. Those could shove it sideways. Nothing could speed it up.

It knew nothing about its own altitude, its attitude or its range to the target. It flew pure proportional line-of-sight guidance under bang-bang control: see the hot thing, move so the hot thing stops drifting in the field of view, repeat until impact.

The seeker was a Hughes design of genuine elegance. Four strips of indium bismuth arranged in a cross, plus four more in logarithmic spirals. The vehicle was spun up to about thirty revolutions per second by the second stage, and the target’s position was read from the pattern in which its image crossed those strips. A Honeywell ring laser gyroscope kept the timing honest.

To work at all, the detector had to be cooled to around minus 450 degrees Fahrenheit with liquid helium. The dewar that supplied it was installed in the F-15 in place of the 20 mm cannon’s ammunition drum, with a second dewar in the missile itself. The cryogenic lines retracted just before spin-up. On the early two-seat test aircraft, the back seat was removed to make room for a helium tank one engineer described as about the size of the robot from Lost in Space.

El Washington Post’s George Wilson had nicknamed the thing the flying tomato can back in 1977. It stuck.

An F-15 Eagle carrying an ASM-135 anti-satellite missile on its centreline station
An F-15A with an ASM-135 on the centreline. The F-16 was never a candidate: it lacked the ground clearance to carry the missile there at all. Photo: U.S. Air Force, via the National Archives
“The F-15 was a real racehorse. We could fly supersonic and we could maneuver it to be in the right kind of a climb… An F-16 didn’t have the ground clearance; you couldn’t put the missile on the centerline of the airplane and take off with it without hitting the ground.”
Maj. Gen. Wilbert D. “Doug” Pearson Jr. (ret.) — USAF, to Air & Space/Smithsonian, April 2018

Waiting in the Officers’ Club

The first attempt was set for 4 September 1985. Pearson was in the officers’ club with General Forrest McCartney, waiting for the call.

The call came, and it was a cancellation. An injunction had been filed — by several Congressmen and the Federation of American Scientists — on the grounds that the required presidential certification had gone in fourteen days ahead of the test rather than the mandated fifteen. A federal judge later refused a second injunction, and the shot slipped nine days.

The flight plan itself had been computed by a team under Jack Anthony at Cheyenne Mountain. It was a twenty-four-hour profile worked out to the minute, and to the second on the missile release. Pearson took off three and a half hours before the moment of impact.

About two hundred miles west of Vandenberg he accelerated to Mach 1.22, pulled 3.8 g into a sixty-five-degree climb, and let go. Except he did not let go — the missile released itself, automatically, at 38,100 feet, by which point the aircraft had decelerated back through the sound barrier to Mach 0.934.

Then there was nothing to see. The intercept happened hundreds of miles above him and he had no way of knowing whether it had worked.

“That’s a Good Altitude”

So he and a friend called Scott, in the control room, had agreed a code beforehand. The version that circulates online usually stops before the best part.

“I’d tell him ‘I’m going to level off at 36,000 feet.’ And if we’ve had a successful intercept, you’ll say, ‘Roger, Aggie-1. That’s a good altitude.’ And if we missed, you’ll say, ‘Roger, Aggie-1. Recommend you go to 28,000 feet’ or some different number. Well, Scott never had to say a word. He just keyed the microphone and I heard all the screaming and hollering and yelling and cheering in the background.”
Maj. Gen. Wilbert D. “Doug” Pearson Jr. (ret.) — USAF, to Air & Space/Smithsonian, April 2018

Aggie-1 was Pearson’s callsign. He is a Texas A&M graduate.

The Miniature Homing Vehicle had hit Solwind at a closing speed of at least fifteen thousand miles an hour. There was no explosion because there was nothing to explode. At that velocity, a thirty-pound object does not need help.

The actual launch, filmed from a chase aircraft.

The Satellite Was Still Working

This is the part the story usually leaves out, and it is the part that mattered most at the time.

Solwind P78-1 was not space junk. It was a Ball Aerospace solar observatory launched in February 1979 and still returning data. By September 1985 two of its seven instruments were still alive, and one of them was the Naval Research Laboratory’s white-light coronagraph — an instrument solar physicists had hoped would produce the first continuous record of the sun’s corona across a full eleven-year solar cycle from above the atmosphere.

The original target was to have been a purpose-built instrumented object. Target problems caused delays, and the Pentagon wanted a shot before Congress closed the window. Solwind’s mission was deliberately extended by several weeks specifically so it could be destroyed, during which it was repeatedly left in an under-voltage condition for days at a time.

NRL physicists who came to work on 14 September were surprised to find there would be no more data.

“I can’t believe that they couldn’t find a piece of space junk, really, instead of a working laboratory. This was a working observatory, so I’m just a little taken aback [by] the SDI people… They particularly made a pitch to the university community, to the scientists, in saying this is a ‘Manhattan Project’ sort of thing, and it’s good science and so forth — and then they turn around and blow up a laboratory.”
David Rust — solar physics programme supervisor, Johns Hopkins University Applied Physics Laboratory, to Science News, 28 September 1985

Asked whether he would go as far as calling it a travesty, Rust did not hedge.

“If you want to say that I called it a travesty, why you can say that. I think that’s a perfectly correct characterization.”
David Rust — Johns Hopkins University Applied Physics Laboratory, Science News, 28 September 1985

There is a final irony in the target selection. Solwind was the first satellite in history to discover a comet. Nine Kreutz-group sungrazers plus one other comet were eventually found in its coronagraph images — several of them decades later, by an amateur astronomer working through the archive.

Nineteen Years of Debris

NASA found out about the plan in July 1985, ran the numbers, and concluded that fragments would still be up there in the 1990s — which meant extra shielding on the space station then being designed. NASA had previously advised the Air Force how to conduct an ASAT test without creating long-lived debris. That plan had died with earlier Congressional restrictions.

The official NASA breakup record lists 285 catalogued fragments. The Union of Concerned Scientists estimates another 800 to 900 pieces above ten centimetres that were never tracked. The last catalogued piece re-entered on 9 May 2004 — nearly nineteen years after the shot.

And the debris behaved strangely. It was almost invisible to optical telescopes; only two pieces were ever seen that way. NASA’s explanation was that plastics inside Solwind had vaporised on impact and condensed onto the metal fragments as soot, blackening them. Infrared telescopes showed the pieces were warm, which supported the theory. The event became a baseline case for what a hypervelocity collision actually looks like, and forced a recalibration of how debris is detected.

An inert ASM-135 ASAT missile on display at the Smithsonian Udvar-Hazy Center
An inert ASM-135 at the Smithsonian’s Udvar-Hazy Center. Fifteen were built; five were flown. Photo: Balon Greyjoy, CC0, via Wikimedia Commons

Three Months Later, Congress Shut It Down

The caption version of this story says Congress banned further tests “the following year”. It was faster than that.

In December 1985 — three months after the shot, in the same calendar year — Congress banned testing the system against objects in space, through the FY1986 appropriations act signed on 19 December. The timing was almost comic: the ban landed one day after the Air Force had orbited two target satellites for the next round.

Pearson’s own account of how the ban came about is worth repeating for its sheer horse-trading candour: a halt in US ASAT tests was agreed by House-Senate negotiators in return for approval of new chemical weapons production.

The ban was renewed in 1986. Two further ASM-135s were flown that year, in August and September, both aimed at stars rather than satellites so as to stay inside it. The projected cost had gone from an estimated $500 million to more than $5.3 billion, and the Reagan administration cancelled the programme in 1988, citing guidance problems, delays and cost growth. Twenty modified F-15As and up to 112 missiles had been planned, split between squadrons at McChord and Langley.

Fifteen missiles were built. Five were flown. One hit a satellite.

Scott Manley’s explanation of the intercept geometry, which is the clearest account of why this was hard.

The Patch

On 13 September 2007, twenty-two years to the day, F-15A 76-0084 sat on the ramp at Homestead Air Reserve Base in Florida with “Celestial Eagle” freshly painted on the nose. The name dates from that day, not from 1985 — there is no contemporaneous 1985 document that uses it.

The idea came from Staff Sergeant Aaron Hartley, the crew chief. The pilot who climbed in was Captain Todd Pearson of the 390th Fighter Squadron, wearing on his left shoulder the same circular patch his father had worn on the original mission.

Retired Major General Doug Pearson and Captain Todd Pearson standing in front of F-15A 76-0084
Doug and Todd Pearson with 76-0084 at Homestead, 13 September 2007. The same airframe, twenty-two years apart. Photo: Senior Airman Erik Hofmeyer, U.S. Air Force

One correction to the version doing the rounds: Doug Pearson did not spend six years leading the programme. The programme ran roughly six years, from 1979. He was an F-20 test pilot until April 1985 and directed the F-15 Anti-satellite Combined Test Force from May 1985 — about four months before he flew the mission. He retired as a major general on 1 January 2005, as commander of the Air Force Flight Test Center.

76-0084 went to storage at Davis-Monthan on 19 August 2010. What happened to it after that is not recorded in any source we could find.

Why Nobody Has Done It Since

Satellites have been destroyed since 1985. China killed Fengyun-1C in January 2007 at 865 kilometres, creating over three thousand trackable fragments and the worst debris event in the history of spaceflight. The US Navy shot down the failed satellite USA-193 with an SM-3 in February 2008, deliberately low. India destroyed Microsat-R in March 2019 at 283 kilometres, deliberately lower still. Russia destroyed Kosmos 1408 in November 2021.

Every one of those was launched from the ground or from a ship. The Solwind intercept remains the only time an aircraft has destroyed a satellite, and no pilot has fired at one since.

NASA groups Solwind and Fengyun-1C together as the two high-altitude tests whose environmental consequences shaped both international guidelines and the way every subsequent test was flown. The reason India and the United States shot low is, in a direct line, that thirty-pound coffee can and the nineteen years it took the pieces to come down.

“[It] had a big impact on our adversaries because they had been very dependent on being able to put up these reconnaissance satellites, and they now knew — by demonstration — we could negate that. I think from their point of view, we made it look easy. We took off, we flew out, we pulled up, we killed a satellite. They never saw us sweat, in other words.”
Maj. Gen. Wilbert D. “Doug” Pearson Jr. (ret.) — USAF, to Air & Space/Smithsonian, April 2018

Preguntas frecuentes

Has a fighter jet ever shot down a satellite?
Once. On 13 September 1985 Major Wilbert D. “Doug” Pearson Jr. launched a Vought ASM-135A anti-satellite missile from F-15A 76-0084 and destroyed the American satellite Solwind P78-1. It remains the only time an aircraft has destroyed a satellite, and no pilot has fired at one since.
How did the ASM-135 destroy a satellite without a warhead?
It was hit-to-kill. The missile’s payload was a 30 lb Miniature Homing Vehicle with an infrared seeker and no explosive at all. It carried no forward propulsion — only 56 full-charge and 8 half-charge divert motors around its circumference that could shove it sideways — and steered itself into the satellite’s path using proportional line-of-sight guidance. The closing speed was at least 15,000 mph.
How did the pilot launch the missile?
About 200 miles west of Vandenberg, Pearson accelerated to Mach 1.22 and pulled 3.8 g into a 65-degree climb. The missile released itself automatically at 38,100 feet, by which point the aircraft had decelerated back through the sound barrier to Mach 0.934. He did not fire it manually and could not see the intercept.
What was the “Aggie-1” radio code?
Because Pearson had no way of seeing whether the intercept worked, he pre-arranged a code with a friend named Scott in the control room. Pearson would announce he was levelling at 36,000 feet; Scott would answer “Roger, Aggie-1. That’s a good altitude” if it had worked, or recommend a different altitude if it had missed. Aggie-1 was Pearson’s callsign, from his Texas A&M background. In the event Scott said nothing — he keyed the microphone and Pearson heard cheering in the background.
Was Solwind a working satellite?
Yes. Solwind P78-1 was a Ball Aerospace solar observatory launched in February 1979, and two of its seven instruments were still returning data in September 1985, including a Naval Research Laboratory white-light coronagraph. Its mission was deliberately extended by several weeks so it could serve as the target. Solar physicists objected publicly; David Rust of Johns Hopkins APL agreed on the record that “travesty” was a fair description.
How much debris did the 1985 test create?
NASA catalogued 285 trackable fragments, and the Union of Concerned Scientists estimates a further 800 to 900 pieces larger than 10 cm that were never tracked. The last catalogued fragment did not re-enter until 9 May 2004, nearly nineteen years after the intercept. The debris was unusually dark and hard to see optically, which NASA attributed to vaporised plastics condensing on the metal as soot.
Why was the ASM-135 programme cancelled?
Congress banned testing against objects in space in December 1985, three months after the intercept, through the FY1986 appropriations act signed on 19 December — one day after the Air Force had orbited two target satellites for the next round. The ban was renewed in 1986. With costs having grown from an estimated $500 million to more than $5.3 billion, and with guidance and schedule problems, the Reagan administration cancelled the programme in 1988. Fifteen missiles were built and five were flown.
Did the same aircraft fly again on the anniversary?
Yes. On 13 September 2007, twenty-two years to the day, F-15A 76-0084 flew from Homestead Air Reserve Base in Florida with “Celestial Eagle” newly painted on the nose — the name dates from 2007, not 1985. The pilot was Captain Todd Pearson, Doug Pearson’s son, wearing the same shoulder patch his father had worn. The aircraft went to storage at Davis-Monthan on 19 August 2010.

Sources: Paul Glenshaw, “The First Space Ace”, Air & Space/Smithsonian, April 2018; Peter Grier, “The Flying Tomato Can”, Air Force Magazine, February 2009; Jonathan Eberhart, Science News, 28 September 1985; NASA Orbital Debris Program Office, History of On-Orbit Satellite Fragmentations, 16th edition; Union of Concerned Scientists, A History of Anti-Satellite Programs; USAF Air Force Flight Test Center history (DTIC); USAF official biography of Maj. Gen. W. D. Pearson Jr.; 482nd Fighter Wing public affairs.

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