Launch of the Energia rocket

On May 15, 1987, the Soviet Union launched the Energia rocket from the Baikonur cosmodrome with a combat station named Polyus attached to its side. The rocket was designed to carry a carbon dioxide laser meant to destroy American satellites, but it failed to reach orbit and crashed into the Pacific Ocean.

Failure due to software error

The failure was attributed to a software bug that caused the spacecraft to rotate 360 degrees instead of 180, leading to the engine igniting in the wrong direction. Polyus fell back into the Pacific Ocean less than 10 minutes after launch, and the Skif program was abandoned.

Soviet response to US defense plans

The Polyus station was part of the Skif program, a Soviet response to the U.S. Strategic Defense Initiative, announced by Ronald Reagan in 1983 and nicknamed "Star Wars" by the press. The Polyus-Skif was intended to serve as a precursor to a laser system capable of attacking American antimissile satellites and possibly other military vehicles.

Rocket's capabilities and the Skif program

The Energia rocket, built to carry the Buran shuttle, could carry 95 tons, making it a suitable platform for the project. The idea of a first launch with a heavy mock-up was born in July 1985, giving rise to Skif-DM, the D for demonstration and the M for mock-up. This version contained only the basic components and a partial reserve of CO2, without a real laser on board.

Launch delays and political pressure

The schedule was intense, with the real Skif developed in one year, from September 1985 to September 1986, and then the tests pushed the launch to February, then to May 1987. During Gorbachev's visit on May 11, Boris Gubanov, chief designer of Energia, asked him to authorize the launch without waiting, fearing heart attacks in his teams.

Weight and technical details

Sources differ on the weight of the Skif-D: 80 tons for Skif-D in most accounts, 100 tons for Skif-DM according to other analysts, equivalent to 12 to 15 adult African elephants. On the night of May 15, 1987, the Energia engines ignited. The launcher combined a central stage with 4 engines and 4 liquid-fueled auxiliary boosters, and it functioned without fault, arcing its trajectory toward the north of the Pacific.

Technical failure and consequences

Polyus then detached, its boosters oriented in the direction of travel. It was supposed to pitch 180 degrees and roll 90 degrees before igniting its engine. This final thrust was supposed to add 60 m/s, or 216 km/h, by burning between 1.5 and 2 tons of propellants. The engine ignited after the half-turn, but the spacecraft's rotation did not stop as planned and continued.

Partial success and program cancellation

Curiously, the Soviets did not view this flight as a complete catastrophe: the launch would have fulfilled about 80% of the scientific and test objectives, including geophysical and military experiments. As for Energia, it had successfully completed its maiden flight, a point on which the consulted sources agree. The program, however, did not survive.

Legacy of the Energia rocket

Skif-D1 and Skif-D2 were supposed to follow about a year apart, but the program was canceled after this failure. The initial plan called for a 30-day mission for the mock-up. Energia, on the other hand, only launched twice, the end of the Buran program putting an end to its career. Its legacy survives in the RD-170 engine family.

Laser station clarification

One nuance remains that the "laser station" abbreviation forgets: no weapon was on board, only a laser mock-up. According to Wikipedia, the plan called for testing the future laser's escape with a xenon-krypton mixture, presented as an experiment on the ionosphere, because a cloud of CO2 would have betrayed the true purpose of the vehicle.