Proton Grounded Until March
Russia will likely keep its troubled Proton booster grounded
until March in order to complete engine upgrades, creating potential
additional delays for the International Space Station, an industry
publication reported November 24.
Aerospace Daily quoted Russian officials who said the Proton
booster, which has failed in two of its last four launches, would
remain grounded until the engines of the second stage of the booster
can be upgraded.
The second-stage engines of the normally-reliable Proton have
been implicated in both launch failures. A Proton crash July 5 was
traced to a fault weld in a turbopump of a second-stage engine, which
led to an explosion that destroyed the stage and caused the upper
stages and payload to crash in Kazakhstan.
While the investigation into the October 27 Proton crash is
still underway, the accident appears similar to the July accident, in
that a failure of the second stage engine was the most likely cause of
the crash. A preliminary report on the crash was delivered to Russian
Prime Minster Vladimir Putin on November 17, and a final report is due
this month.
Engines in the boosters involved in both failures came from
the same batch produced by Russia's Voronezh factory in 1993,
Aerospace Daily reported. They were made after a nine-month plant
shutdown, and officials, including Russian Space Agency chief Yuri
Koptev, speculate that workers and tools were not properly certified
before production resumed.
Voronezh had already been modernizing the Proton's
second-stage engines, work that had been accelerated after the July
accident. While the upgraded engines should be completed by the end
of this year, the work needed to install the engines on existing
Protons and prepare them for launch will push back the next Proton
launch until at least March.
That date would mean an additional delay for the International
Space Station and its Zvezda service module, to be launched on a
Proton. Earlier in November Russian officials had said that the
launch of Zvezda would not occur before February, although they
claimed problems with American components were behind the delay.
Moreover, while the Proton could return to service in March,
it is not clear the Zvezda would be the first payload for the Proton.
There are several commercial payloads due to be launched on Protons,
and officials may not wish to place a valuable payload such as Zvezda
on the first upgraded Proton.
A new launch date for Zvezda will likely be announced after a
General Designers' Review of ISS, scheduled to be held in Moscow
December 2, Aerospace Daily reported.
In knowledge we trust!