Soyuz launch with Falcon Eye-2 postponed
The liftoff of the Soyuz ST-A rocket planned for Thursday had to be delayed for at least 24 hours due to problems with its Fregat upper stage, the official Russian TASS news agency reported. The mission launching from a jungle launch pad in French Guiana was to deliver the Falcon Eye-2 reconnaissance satellite for the military of the United Arab Emirates, UAE.
Soyuz VS24 mission at a glance:
History of the mission
On December 9, 2014, the European consortium Airbus Defense and Space announced that it had been selected by the Armed Forces of the United Arab Emirates to be the prime contractor in the development and launch of two "high-performance" optical observation satellites. The contract for the project was signed in August 2014 and entered force at the time of the announcement, the Airbus said. In addition to the construction of the satellite, the company also got the responsibility for the development of a ground system for monitoring, receiving and processing images from the spacecraft as well as training the UAE's specialists to operate the satellite after its deployment in orbit.
At the same time, France-based Thales Alenia Space announced that it had won a contract from the UAE's military to build a "very-high resolution" optical payload for the Falcon Eye pair, as well as the data transmission system and the image-processing system. The company was also responsible for the co-engineering and validation of the overall system.
The original Falcon Eye satellite was launched on July 11, 2019, but it failed to reach orbit because of a failure of the Vega launch vehicle during the operation of its second stage. The government of UAE then made the decision to switch the launch of the follow-on spacecraft to the Soyuz rocket operated by the European consortium Arianespace from its site near Kourou, French Guiana.
Arianespace was mostly mum about the preparations for the mission, but Head of Roskosmos Dmitry Rogozin boasted on his Twitter account on March 2, 2020, that the Soyuz rocket for the launch of the Falcon Eye-2 reconnaissance satellite had been rolled out to the launch pad in French Guiana and that the liftoff had been scheduled at 04:33:28 Moscow Time on March 6.
Delay of the first launch attempt
The Soyuz ST-A rocket, carrying Falcon Eye-2 satellite, was originally scheduled to lift off from the ELS launch facility in French Guiana on March 5, 2020, at 8:33:28 p.m. EST (04:33:28 Moscow Time on March 5). It would be 10:33 p.m. in French Guiana.
However before the end of the business day in Moscow on March 5, the TASS reported, quoting an unnamed industry source, that the mission had to be postponed until the next day due to issues with the upper stage. There was a possibility that the launch could pushed back even further, but the final decision would not be made before repeating the integrated tests of the launch vehicle, TASS said.
Later in the day, Arianespace published a statement saying that "due to additional checks to be performed on the Fregat upper stage of the Soyuz flight VS24, the launch initially scheduled for March 5, 2020 from the French Guiana Space Center is postponed. The launch vehicle and its satellite payload have been placed in stand-by mode and maintained in fully safe conditions," the company said. Since the announcement had not contained a new launch date, it appeared that the mission had been postponed indefinitely.
On March 6, a Russian industry source said that the mission was postponed until early April due to customer's demand to replace Fregat upper stage on the rocket, even though Russian specialists proposed to fix the problem on the current booster. The Fregat stage, originally slated to carry the CSO-2 satellite and already at the launch site, would be used as a replacement, the source said. The launch of CSO-2 was previously planned for April 10.
According to a post on the Novosti Kosmonavtiki web forum, lack of signal on one of three channels controlling fuel supply to a DMT thruster of the Fregat stage caused the delay. A switch controlling system was a possible culprit, the poster said.
On March 15, 2020, due to the coronavirus pandemic, the French space agency, CNES, operating the Guiana Space Center, ordered to stop ongoing launch campaigns at the site and all unfinished construction. The only exception were the operations to bring the launch vehicles, payloads and facilities in safe condition and their monitoring.
The exact launch timeline and other basic details of the mission scenario have not been officially detailed but it is safe to assume that the launch vehicle will follow a typical flight profile required to deliver an observation satellite into near-polar orbit, which takes the spacecraft from North Pole to the South Pole and back, with the orbital plane of the mission nearly perpendicular to the plane of the Equator. The typical altitude for such missions is usually around 800 kilometers making the orbit Sun-synchronous, meaning that the satellite would periodically appear over the same region on Earth at the same time of the day and thus guaranteeing consistent lighting conditions over the photographed areas.
To reach the polar orbit, after a few seconds in vertical ascent over the South-American coast, the Soyuz rocket will head north over the Atlantic Ocean. The four boosters of the first stage will be dropped around two minutes into the flight, followed by the separation of the payload fairing around a minute later.
The second stage will fire until five minutes into the flight, when the third stage should take over. The first stage boosters and the two segments of the payload fairing will fall into the Atlantic south of the Equator and the third stage will impact west of Greenland.
The Fregat upper stage might then maneuver to insert the satellite into its orbit. Shortly after the payload separation, the Fregat is usually pre-programmed to perform a series of maneuvers leading to its fiery destruction in the Earth's atmosphere. Indeed, shortly before the mission, the authorities published a warning to air and sea traffic to avoid a remote region of the Indian Ocean, over which Fregat debris were expected to be scattered during the reentry.
The Soyuz rocket for the second Falcon Eye mission is being erected on the launch pad in French Guiana. Click to enlarge. Credit: ESA