MOSCOW — After months of insisting that Russia’s first interplanetary mission in more than a decade would lift off before the end of October, Russian space officials conceded in late September that the launch of Phobos-Grunt would have to wait until 2011 when the next favorable Mars launch opportunity rolls around. To industry insiders and critics of the way the program has been managed, the two-year delay was the foreseeable result of organizational and technical challenges that have dogged the mission from the beginning.

More than a week after the official decision was made to postpone the mission, the Russian space agency, Roskosmos, had not publicly acknowledged the delay. The job of breaking the news to the mission’s many international participants fell to the Russian Academy of Sciences’ Space Research Institute, the Moscow-based organization running the Phobos-Grunt science program.

In a Sept. 21 e-mail to Phobos-Grunt payload providers in Russia and abroad, Space Research Institute Director Lev Zeleny said that the decision by the Russian Academy of Science and Roskosmos to forfeit the 2009 launch window was necessary to allow for additional spacecraft and subsystem testing aimed at “increase[ing] reliability of the mission.”

In an interview with the Russian government newspaper Rossiskaya Gazeta posted Sept. 29 on the Roskosmos Web site, Roskosmos chief Anatoly Perminov acknowledged that Phobos-Grunt was postponed but downplayed the technical issues.

“Scientists hope to clarify the nature of the Phobos surface. It is necessary in order to better design the regolith sampling device. If the regolith turns out to be too solid, an incorrectly chosen method of sampling could nullify this very expensive expedition,” Perminov said. “Besides, we still haven’t reached a 100 percent backup reliability of our continuous communications with the spacecraft at every phase of the flight. Also a more reliable development of all components [of the spacecraft] is needed.”

Louis Friedman, the executive director of the Pasadena, Calif.-based Planetary Society, reacted to the long-expected delay announcement with a mix of regret and relief. When Phobos-Grunt finally launches, it will carry a collection of microorganisms to Mars and back inside a tiny biomodule the Planetary Society sent to Russia this summer for integration with the spacecraft.

“Of course we are sorry that it was delayed, but at this stage … if it hadn’t been delayed I might have said that I am sorry to hear that,” Friedman told Space News, expressing a sentiment common to many project participants that the spacecraft was simply not ready for the ambitious and rigorous mission.

To many critics behind the scenes, Zeleny’s e-mail and Perminov’s comments understate the amount of work that has to be done to get Phobos-Grunt ready for launch. Industry sources told Space News that Phobos-Grunt’s onboard flight control system — known in Russia as the BKU — is far from ready and that much more than testing is required to clear it for launch in 2011.

More work also is needed to get Russia’s ground control facilities ready to support its first deep space mission since Mars 96, an orbiter and lander lost in a November 1996 launch failure.

As word spread among Phobos-Grunt’s many international contributors that a launch this year was looking less and less likely, work on at least some of the 20-plus instruments planned for the mission slowed. At least one payload that would not have been ready in time for a 2009 launch, a tiny Mars meteorological probe contributed by Finland, could make it back onto the mission as a result of the delay, sources said.

But the far biggest issue for Phobos-Grunt, sources familiar with the program said, was the flight readiness of the onboard flight control system.

Problems with the spacecraft’s onboard flight control system can be traced back to an early, controversial decision by Phobos-Grunt’s lead contractor, NPO Lavochkin, to build the probe’s BKU in house rather than outsource the job to OKB Mars, the Moscow-based firm that supplies most of Lavochkin’s flight control computers.

While critics of the decision said that Lavochkin management had a financial motive for keeping the BKU work in house, Lavochkin said at the time that OKB Mars’ flight computers were too large for Phobos-Grunt.

NPO Lavochkin spokeswoman Natalya Galich declined to comment on Phobos-Grunt or make program officials available for an interview.

A source familiar with the matter said NPO Lavochkin put a relatively new and inexperienced team in charge of the flight control computer project. While the integration and software work was kept in house, the development of the BKU electronics was outsourced to Moscow-based Tehkhom, a company spun off from NII Argon. Like OKB Mars, NII Argon was a longtime developer of onboard computers for Soviet-era spacecraft.

Tehkhom, according to sources, promised Lavochkin it could deliver lighter, better-performing components for the BKU than it could get from OKB Mars.

“Tehkhom provided computers with fairly high technical characteristics and progressive technologies, but they only provided the hardware,” one expert familiar with the situation said. “All this hardware had to be integrated together and provided with common software.”

While the Tehkhom components were delivered as promised, Lavochkin’s in-house BKU team fell behind on integration and software development.

According to sources familiar with the matter, Lavochkin has done component-level testing on parts of the BKU but has yet to run the fully integrated flight control system through a complete mission sequence.

A critic of Lavochkin’s handling of the project said that Phobos-Grunt still might not be ready in 2011 unless development of the flight control system is reorganized.

Meanwhile, the two-year delay will give Roskosmos enough time to upgrade a ground control station in Medvezhiy Ozera near Moscow to serve as a redundant communication site for Phobos-Grunt. The spacecraft’s main control site is located in Ussuriysk in the Russian Far East.

Aleksandr Zakharov, the deputy director of the Russian Space Research Institute, told Space News that a lack of backup ground control facilities had been another argument in favor of postponing the mission to 2011.

While ground control upgrades were running behind, critical spacecraft tests also were slipping uncomfortably close to the late September deadline for shipping Phobos-Grunt to the Baikonur Cosmodrome in Kazakhstan for a late October launch aboard its Zenit 2SB rocket.

In the end, mission officials had no choice but to call a delay.