Proton over-fueling dooms 43rd GLONASS mission

In a midst of a hectic launch schedule, a Proton M rocket failed during a mission to deliver a trio of Uragan-M/GLONASS satellites on Dec. 5, 2010. Unbelievably, the upper stage of the rocket plunged into the ocean because too much propellant had been loaded onboard.

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A Proton rocket lifts off with a trio of GLONASS satellites on Dec. 5, 2010.

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Preparations for flight

The 43rd mission to deliver a trio of Uragan-M satellites for Russia's GLONASS navigation network would be also the first flight for the Proton's modified fourth stage designated Block DM-03. The launch was first reported to be planned in November 2010, and by the middle of August of the same year, it was thought to be on schedule for Nov. 30, 2010. However this date would have to be confirmed following a preceding Proton mission with GLONASS satellites then scheduled for Sept. 2, 2010. The 43rd mission was later expected on Dec. 10, 2010, and was ultimately set for Dec. 5, 2010.

GLONASS trio plunges into the ocean

The launch vehicle lifted off from Pad 24 at Site 81 in Baikonur Cosmodrome at 13:25:18 Moscow Decree Time. According to the initial statement of the Russian space agency, the payload section (which included the Block DM-03 upper stage and three GLONASS satellites) separated in what was supposed to be the initial parking orbit 10 minutes after the liftoff. However, according to the follow-up official report, the mission's payload had been delivered into a wrong orbit.

According to unofficial reports, at 14:01 Moscow Time or 26 minutes after reaching its initial orbit, the upper stage was scheduled to fire for six minutes, however before this could happen, the vehicle entered a suborbital trajectory, apparently resulting in the reentry into the Earth's atmosphere. The semi-official RIA Novosti news agency quoted industry sources as saying that before the separation of the Block DM upper stage, the launch vehicle had already deviated around eight degrees from its nominal pitch trajectory, resulting in the reentry and loss of satellites over the Pacific Ocean. The remnants of the vehicle reportedly splashed down 1,500 kilometers northwest of Honolulu.

A press-release by RKK Energia, which built the upper stage, confirmed the reentry of the payload and said that an abnormal performance of the Proton rocket had sent Block DM-03 with its cargo into the wrong flight path.

On the morning of Dec. 6, 2010, Russian media reported that a programming error in the flight control system had likely put the vehicle onto a wrong trajectory and that no mechanical problems with the rocket had been detected. Gennady Raikunov, the head of TsNIIMash research institute, the main expertise and certification center of the Russian space agency, was expected to lead the failure investigation commission.

The investigation

On Dec. 7, 2010, Russia's semi-official Interfax news agency reported that the cause of the Proton launch failure had been traced to the overloading of the upper stage. The agency quoted an unnamed industry source as saying that the investigation commission was considering a scenario where an extra ton of propellant (two tons according to other sources) had been loaded into the Block DM-03 upper stage, as the most probable culprit in the accident. As a result of the heavier load, at the moment of separation between Proton's third stage and Block DM-03, the vehicles were flying around 100 meters per second below nominal velocity. A ground simulation of the flight conditions reportedly confirmed this failure scenario.

On the same day, International Launch Services, ILS, announced that preparations for the next scheduled Proton launch with the KA-SAT satellite on December 20 were continuing. The fueling of the Briz-M upper stage for this mission was completed on Dec. 6, 2010, ILS said. According to the company's press-release, an interim report was expected "in approximately one week that may include details on the respective performance of the Block DM-03 upper stage built and operated by RKK Energia and the three lower Proton M stages, all built and operated by Khrunichev." Such phrasing obviously hinted at the possibility of isolating the latest launch failure to the Block DM-03 upper stage, thus clearing the next mission with Briz-M for flight. ILS stressed that the failed mission "was a maiden flight of the Block DM-03 upper stage, which is a derivative of Energia’s Block DM."

Industry sources told that Block DM-03 has approximately 25 percent larger propellant tanks than the previous version of the stage. With 2,000 kilograms of extra propellant, which is believed to have been mistakenly loaded onboard, the tanks would be filled close to the same level as the old ones - the oxygen tank would be 90 percent full with a 25-percent reserve load. (On Dec. 8, unofficial sources said that liquid oxygen overload onboard Block DM-03 had been 1.6 tons). As it transpired by Dec. 10, Block DM-03 had new (propellant level) sensors, however loading of propellant was conducted according to old instructions.

The Block DM–03 upper stage was developed primarily to increase the performance of Zenit-3 rockets flying with the Sea Launch and Land Launch ventures.

If the current failure scenario is confirmed, the Proton could be cleared for return to flight as soon as December 10 or even December 9, 2010, sources told.

On Dec. 9, 2010, Interfax reported that the head of the Russian space agency, Roskosmos, Anatoly Perminov, could lose his job over the Proton failure. In the wake of the failed launch, Perminov came under fire for his characterization of the accident as "not a catastrophe," since there was no loss of life or damage to launch facilities. Sergei Prikhodko, a powerful aide to the Russian president, publicly expressed his dismay at such an approach in the assessment of an important federal project. The accident was also accompanied by Russian publications about misappropriation of funds, corruption and nepotism at Roskosmos and its contractors responsible for the implementation of the GLONASS project.

In the ultimate fallout from the Proton failure, on Dec. 29, 2010, the Kremlin's press-service announced that based on the report delivered by Vice Prime Minister Sergei Ivanov, the head of Roskosmos Anatoly Perminov had been officially reprimanded for the accident. In the meantime, Perminov's deputy Viktor Remishevsky and Vice President of RKK Energia responsible for launch vehicle systems Vechaslav Filin lost their jobs. Filin was a veteran of Soviet rocketry, with a resumé including a prominent role in the development of the super-heavy Energia launcher.

Trial to begin into the over-fueled Proton failure

More than six years after the Proton's failure to deliver the 43rd batch of GLONASS satellites, four people will go on trial on accusations of causing the rocket's upper stage plunge into the ocean.

The district court in the town of Korolev, where the developer of the doomed Proton's Block DM-03 stage is based, set the opening of the criminal trial for March 14, 2017, the Russian press reported quoting court officials.

According to the office of Russia's federal Prosecutor General, employees at RKK Energia used a wrong formula during the fueling of the company's Block DM-03 upper stage, which received 1,582 kilograms of extra liquid oxygen above the maximum allowable limit. The prosecutors allege that the department head at RKK Energia Stanislav Balakin, the unit head Aleksandr Martynov and his deputy Sergei Lomtev, while being responsible for the development of operational documentation for Block DM-03, failed to ensure that their subordinate engineer Yuri Bolshigin had completed the on-time adjustment of the computation formula controlling the operation of the fueling system.

The investigation allegedly established that the change request had arrived to a proper department, however it had been processed as already completed. As a result, the computation formula had remained unchanged by the time the modified Block DM-03 stage arrived for fueling. The prosecution accused the four men of knowingly approving the faulty operational documentation and failing to correct the computational error.

According to the prosecutor's office, the rocket's failure to deliver satellites for the nation's GLONASS navigation network cost more than four billion rubles ($68.7 million).


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The article and photography by Anatoly Zak; Last update: December 13, 2021

Page editor: Alain Chabot; Last edit: March 6, 2017

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Block DM-03 during processing in Baikonur. Credit: RKK Energia

GLONASS-M satellite

GLONASS-M (Uragan-M) satellite. Credit: NPO PM