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Russian Soyuz rocket returns to flight

Anatoly Zak, Spaceflight Correspondent
Jun 6, 2015, 1:17 UTC

Sen—Five weeks after a botched launch to deliver a space station cargo mission, Russia's workhorse Soyuz booster returned to flight Friday.

A Soyuz-2-1a rocket—exactly the version of the launch vehicle that was involved in the April 28 failure—lifted off from Pad no. 4 at Site 43 at Russia's military launch site in Plesetsk on June 5, 2015, at 18:24 Moscow Time (15:24 UTC, 11:24 a.m. EDT), according to the official Russian media.

Several minutes after the launch, a spokesman for the Russian Air and Space Defense Forces confirmed that the launch had gone as scheduled and the spacecraft had reached its orbit.

The launch vehicle is believed to be carrying a Kobalt-M (Cobalt-M) photographic reconnaissance satellite. Spacecraft of this type are used to deliver large-format film inside cone-shaped capsules, which parachute back to Earth and land in Southern Russia. Although the resulting images reveal details as small as 30 cm (12 in) in size on the Earth's surface, the delivery system is considered antiquated and in the process of being phased out.

Following the liftoff, the launch vehicle headed northeast across most of the Arctic Ocean to reach a near-polar orbit. It puts the spacecraft on a path almost perpendicular to the Equator. As a result, the satellite will be able to train its powerful telescope at almost any point on Earth, as the planet rotates below it.


Diagram showing the sequence of events after the latest launch. Image credit: Anatoly Zak/

Ironically, Friday's launch might be followed by another mission of the more powerful rocket in the family—Soyuz-2-1b, carrying the third Persona satellite, which was designed to replace Kobalt-M. The Persona is able to deliver high-resolution images in near-real time, however its introduction was plagued with technical problems, leading to years of delays and making it necessary to keep Kobalt-M out of retirement.

Along with their military function, both of these Soyuz launches take an additional role of ensuring that the rockets of these type can operate safely after the April accident, which led to the loss of the Progress M-27M cargo ship bound to the International Space Station (ISS).

Although the Russian space agency, Roscosmos, declared the investigation completed, all eyes will be on the performance of the rocket's third stage. According to the official conclusions, unique dynamic properties between the Progress vehicle and the third stage of the Soyuz-2-1a rocket led to the loss of the spacecraft. The agency has yet to announce the corrective actions taken to enable Progress launches onboard Soyuz-2-1a. All but one of 148 Progress launches on older Soyuz-U rockets were successful as was the first attempt to launch Progress on Soyuz-2-1a last year.

In the wake of the Progress M-27M failure, all Soyuz launches were grounded and the return of the Soyuz TMA-15M with three members of the ISS crew was postponed from May 14 to June 11. The next Soyuz launch with the crew is now scheduled for July 24.

Friday's Soyuz-2-1a liftoff was previously scheduled for May 15, 2015, however it was also postponed after the Progress M-27M accident. As is often the case for military launches, preparations for the mission went behind a veil of secrecy and the upcoming liftoff was publically announced only a few hours in advance.