Projects: Solar Sailing
The End of Cosmos 1, the Beginning of the Next Chapter
By Louis Friedman
September 30, 2005:
Cosmos 1 was—and is—a great effort, and one
we are proud The Planetary Society tried to do. Our independent grassroots
organization built and launched a spacecraft whose technology promises to
one day open up interstellar travel. We shared the adventure of space exploration
and captured the hearts of millions worldwide. To get as far as we did was—by
itself—a
great accomplishment, and The Planetary Society board, staff, and technical
team, together with our partners at Cosmos Studios, are dedicated to trying
again.
With our members’ support, we are raising funds to build and fly another
solar sail, and we are seeking new sponsors. We are evaluating technical options,
and we are committed to finding a launch vehicle that won’t fail us
next time. Our Russian colleagues at the Lavochkin Association, who built
Cosmos 1, and the Institute for Space Research (IKI), who were in charge of
the electronics, are doing their best to help us, while taking into account
the hardware, software, and intellectual investment we have already made.
We retain high confidence in our technical team because, as far as we know,
our spacecraft would have worked. Nevertheless, we are taking a few months
to do a “lessons learned” evaluation and put together a plan for our new
attempt to fly the world’s first solar sail spacecraft.
Report on the Volna Failure and the Loss of Cosmos 1
We now have new information on what most likely happened to Cosmos 1. Although
we do not know for certain, it looks like the spacecraft never separated
from the rocket or made it to orbit.
The Volna rocket’s first-stage shut down prematurely when its core
engine turbo pump assembly malfunctioned. Telemetry data show that the assembly
vibrated abnormally at a frequency consistent with its rotor failing. Earlier
Volnas, although extremely reliable, had experienced similar problems. A
design upgrade had been made on some Volnas to correct the problem.
Unfortunately,
our rocket was not among those that were upgraded.
The final report from the Makeev Rocket Design Bureau, the Volna’s
manufacturer, describes telemetry covering just less than 6 minutes of flight
over the Barents Sea. The main engine of the first stage stopped at 83 seconds,
but steering engines (used for roll-pitch-yaw control) continued firing for
an additional 50 seconds. At that point, the rocket had an altitude of 75
kilometers (45 miles). With its motors shut down, the rocket continued in
parabolic free-flight, and about 5 minutes into the flight and at an altitude
near 30
kilometers (18 miles), the data show deceleration from the atmosphere until,
about 1 minute later, the rocket plunged into the sea.
The Makeev team concluded that the first-stage engine failure was random
and “that
it cannot be systematized in terms of error-free running periods during the Volna
service life.” That is, they say that no prediction can be made about when
the turbo pump problem will occur on future Volna flights. Nonetheless, the report
continues, “the first stage engine failures resulted from the design features
of the engines that were manufactured without regard for the Design Documentation
upgrade intended to improve engine reliability.”
Within a few hours after launch, it appeared that portable tracking stations
in the Kamchatka Peninsula and Majuro in the Marshall Islands, as well as
the Panska Ves ground station in the Czech Republic, had received signals
that correlated with the scheduled times of transmission from the spacecraft.
How could this be? It might have been that the first stage of the rocket
had separated and it fell alone into the sea, while the rest of the rocket
stages worked and carried Cosmos 1 into a very low Earth orbit. Makeev could
not tell us otherwise at the time.
After closely examining the signals in the weeks that followed, we eliminated
the Panska Ves signal (it turned out to be of the wrong frequency) and the
Majuro signal (which detailed analysis showed was probably radio-frequency
interference). The Kamchatka data, however, remained strongly suggestive
of a spacecraft signal. It was only after the IKI team failed to reproduce
the signal’s characteristics
on the ground, and an American group we put together showed that the data
could not match reasonable Doppler levels, that we lost hope in the possibility
that the spacecraft ever reached orbit.
Leaving no stone unturned, the IKI team continued to listen from a tracking
station in Tarusa, Russia, and we continued to analyze putative signals until
we could finally conclude that it was unlikely that any signal came from
the spacecraft.
We now have the final Makeev report in hand, plus additional analyses from our
Russian colleagues at IKI and American colleagues of The Planetary Society.
We are comfortable with the conclusion that Cosmos 1 never made it to orbit
because the launch vehicle failed. But we are not comfortable with the reason
it happened: the Volna selected for our payload had not been upgraded to correct
a known failure mode. We will not fly on a Volna again. We’ve learned
that lesson—and it was certainly a hard one. We are now ready to find
a new launch vehicle, establish better launch vehicle interfaces, and try again
to fly the first solar sail spacecraft.
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