Do
We Really Need So Many Satellites?
US Agency Admits Underutilizing Resources
US Agency Admits Underutilizing Resources
While the international debate about space debris mitigation is getting ever more intense, one might wonder whether all the cubesats, constellations, or communication satellites newly launched or planned are really needed. Are all the existing capacities necessary and fully utilized? New concerns might arise after the revelations, made by the U.S. Defense Information Systems Agency (DISA) representative Cindy Moran at the Global Milsatcom Conference on November 28, were reported by Space News.
According to Moran, out of the $ 1
billion commercial satellite capacity purchased by the U.S. Government every
year, only 3-5 % on average is used on a daily basis. “It’s like buying a
Smartphone, with a contract, and then never turning it on!” said Moran, the
director of network services at DISA. Especially the American tax payers
probably won’t be particularly happy upon hearing such news.
While the unpredictable nature of
military usage of satellite telecommunication services is definitely one part
of the problem, additional responsibility for the incredible waste of satellite
bandwidth lies on nothing else but poor management. “I don’t get to reallocate
across the spectrum if the customer that is ostensibly using it is not using
it,” Moran said. “I am buying at the commercial tariff rate.”
The U.S. Government, and the
Department of Defense in particular, is the world’s largest customer for
short-term leases of commercial satellite capacity. As Moran explains,
various governmental users don’t coordinate with each other when it comes to
sharing the purchased satellite bandwidth capacity. Moran fears that such
inefficiency, together with other blunders, might affect the future willingness
of the U.S. Congress to increase funding. “Having satellites in orbit and ready
to operate well before the associated ground infrastructure is ready does not
give us a whole lot of credibility when we go back to them to ask for
additional funding for satellite capacity,” she said.
Moran believes that changes proposed
recently by DISA regarding the procedures for satellite capacity purchases
might help tackle the problem. The new procurement tool, called the Future
Commercial Satellite Communications Services Acquisition (FCSA), opens the
system to new players allowing greater competition and quicker access to
emerging technologies. The main drawback of the new arrangement is increased
length of contract negotiating and making satellite capacity available. Also
the move to the Internet Protocol planned by DISA is expected to improve the
situation.Epsilon
Rocket Data Stolen by Hackers
On Friday November 30th, the Japanese Aerospace Exploration Agency (JAXA) announced an investigation into a possible data leak relating to its Epsilon rocket due to a computer virus.
“The data stolen from the space agency included information about the
Epsilon, a solid-fuel rocket still under development,” said New York Times
reporter Martin Fackler. “While the Epsilon is intended to launch satellite and
space probes, solid-fuel rockets of that size can also have a military use as
intercontinental ballistic missiles.”
The news, first reported by the Kyodo news agency, stems from discovery of
spyware on November 21 on one of JAXA’s personal computers at Tsukuba Space
Centre, northeast of Tokyo. Although the computer was immediately disconnected
from the local area network, the virus was found to be secretly collecting data
to be sent outside the agency.
Epsilon is a small next-generation solid propellant rocket. The program
started in 2007 and the maiden flight has been already scheduled for autumn
2013. Epsilon is supposed to join the existing H-IIA and H-IIB liquid engine
rockets, providing Japan the capability of competing with the US, Europe and
Russia as a satellite launch vehicle provider. Epsilon will also feature a new
cost-saving technology. In fact, the rocket is going to have the capability to
be remotely controlled by a personal computer.
The security breach, which included engine parameters, involved more
than data just on Epsilon. According to an agency statement, data on H-IIA,
H-IIB, and the Epsilon’s ancestor, MV-5 may also have been leaked. The
investigation is now focused on finding the malware’s origin. JAXA cannot
confirm if the virus is a stray one or the result of a hacker attack. However,
this situation is not entirely new. In early September, it was reported that
many Japanese defense companies were targeted by similar information-stealing
viruses. The origin of some of those has been traced to China.
According to Motohiro Tsuchiya, professor at Keio University and member of a
government cyber security advisory body, attacks on the Japanese system
are increasingly sophisticated and subtle. JAXA has been targeted before, when
technical specifications for the H-IIA were stolen
from a laptop in 2011. Nor is Japan the only target. In 2008 a virus
was found on a laptop aboard the International Space Station and in 2007-2008,
two of NASA’s satellites
were hacked. More recently, British Aerospace has confirmed that its
computers were breached by Chinese hackers stealing details about the US F35
Joint Strike Fighter.
Related stories: Japan Epsilon Rocket Data Leak Is Probed By Nation's Space Agency
Japan confesses data breach on Epsilon rocket
Delta
4 Investigation Uncovers Anomaly Sequence; X-37B Cleared for Launch
On October 4, a United Launch Alliance
(ULA) Delta 4 rocket took off, carrying a GPS satellite. Low thrust in its
upper stage could have resulted in a misplaced satellite that day but for a
successful compensation using reserve fuel. As a result of the anomaly, Delta 4
flights were delayed, as was flight of the X-37B
which launches from an Atlas 5 using the same engine family, the RL-10, that
experienced the anomaly.
It now seems that an investigation
has uncovered the main events of the anomaly, as reported by Spaceflight
Now. When the Delta 4′s upper stage ignited, a leak began above the
trust chamber. Each of the subsequent burns produced less thrust than planned
due to the leaking propellant. In what turned out to be a combination of good
planning and sheer luck, the closed loop guidance system observed the subnormal
thrust and compensated using reserves. The satellite was luckily below Delta
4′s lift capacity, so there was more reserve available to draw upon than is
usually the case. After placing the GPS satellite in its intended orbit,
the upper stage even had about 30 seconds of burn left in it. “We were later
informed by our GPS customer that this was the most accurate placement of the
three GPS 2F spacecraft that have been launched,” said ULA vice president
of mission operations Jim Sponnick.
The guidance system more or less saved this mission on its own, since
mission control would have been unable to develop a solution in th available
time. In fact, they were not able to precisely quantify the leak until after
the fact, leaving great uncertainty at the time as to whether the propellant
reserves would be adequate to compensate.
ULA has still not discovered what could have caused the leak in the first
place. They are in the process of narrowing potential causes down from an
initial brainstorm of over 500. One of the first steps was to evaluate which of
these potential causes would have crossover – i.e. would also impact the
RL10A-4 engine used by Atlas 5′s upper stage. Officials with both ULA and the
US Air Force seem convinced that crossover causes have been adequately
assessed, since they have put the third X-37B flight back on the launch pad.
The X-37B Orbital Test Vehicle 3 (OTV-3) space plane is now slated to launch
on the afternoon of December 11. This is the third test flight of the
snub-nosed shuttle-esque vehicle and the first reflight of an OTV. As usual,
the Air Force is keeping mum on the duration and mission of the reusable space
plane. The last X-37B test flight remained aloft for 468 days, well beyond its
designed flight duration of 270 days.
All ULA launches are expected to be back on scheduled by mid-February.
Related Articles:
Breeze-M Fails Again
On December 8 at 17:13 Moscow time, a Proton-M rocket with Breeze-M upper
stage launched from Baikonur Cosmodrome carrying Yamal-402, a communications
satellite built by Thales Alenia Space for the Russian-owned Gazprom
company. Instead of announcing successful separation nine hours later,
International Launch Services (ILS) found itself announcing an anomaly:
“Preliminary flight information indicates that the 4th and final burn of
the Breeze-M engine ended about four minutes early and subsequently
separated [from] the spacecraft.”
It seems that it was not just the final stage that was anomalous. The three
preceding maneuvers and external tank separation had been concluding
increasingly earlier than scheduled, Anatoly
Zak reports. The result: Yamal-402 was placed in a perigee of 3,100
km instead of the intended 7,470 km. It is reported that the apogee
is pretty close to the intended 35,696 km and two maneuvers executed by the
satellite’s own propulsion system may be sufficient to place it in an
operational orbit. The maneveurs are expected to reduce Yamal-402′s operational
life by about four years.
This is the third Breeze-M failure Khrunichev has suffered in the past 16
months. The space industry restructuring
prompted by the last incident has not even begun, while a new investigation is
being opened into the latest Breeze-M disaster. ”In parallel with the
State Commission, ILS will form its own Failure Review Oversight Board (FROB),”
said international Proton marketer ILS in a statement. ”The FROB will
review the commission’s final report and corrective action plan, in accord with
U.S. and Russian government export control regulations.” Fortunately, it
is unlikely that a debris event will occur this time around, unlike the October
16 explosion
that followed an August 6 Breeze-M
failure.
Proton manufacturer Krunichev executed three successful launches between the
two most recent failures, but that is unlikely to reassure Mexican satellite
operator Satmex, whose December 28 launch will almost certainly be postponed.
Satmex’s business is already on shaky ground, and inability to put Satmex 8 in
place before Satmex 5 runs out of fuel in May 2013 could ring the company’s
death knell. Satmex 5 was launched in 1998 and lost its backup propulsion
system several years ago.
The Russian Pioneers of Space Safety: Reinventing Rocket Design
After working in rocket design for
23 years, one may think it could be difficult to re-invent the profession, but
that wasn’t true for Professor Valery Trushlyakov. Trushlyakov contributed to
the design of Cosmos 3M, one of the most reliable launchers ever built but also
nowadays one of the major contributors to low Earth orbit debris,
having left many rocket bodies orbiting uncontrolled. Trushlyakov is now
leading a project with the aim to avoid creating new debris from
launchers’ upper stage but also to clean the existing space debris.
The gasification system, developed
by Trushlyakov and Victor Shalaj for reducing the harm from toxic fuel
in Proton’s first stage was the starting point for a new system concept, able
not only to make a rocket clean in flight, but also to direct it to a specific
landing location. In fact, retrieving rocket body parts that have fallen to
Earth is still an issue, especially if you consider the geography of the
Russian dropping zone, with mountains, lakes, immense taiga, frozen for the
greater part of the year.
Trushlyakov explained that they soon
realized that the technology used to reduce toxic waste for the rocket’s fuel,
could also be used to direct its landing. Every rocket has a certain percentage
of propellant not used after the separation of the stage as margin. This
unused propellant in the end represents a loss in the total payload capacity.
The system that Trushlyakov and his team studied, in cooperation with
Politecnico di Milano, is an Autonomous Onboard De-orbiting System or ADOS. The
goal of ADOS is to take this propellant margin and make it useful.
The liquid propellant in the tank, once gasified (link to the
previous article), is used to feed a Gas Rocket Engine (GRE). The GRE was
built in the ’60s by Valentin Petrovich Glushko, principal soviet designer of
rocket engine, but it was never used. This approach both reduces the harm from
pollutant products and redirects the rocket to a safe and more accessible drop
point. For upper stages this system can also be used to give additional
burns to de-orbit the stage after the payload’s deployment with few maneuvers.
ADOS can basically be used for every liquid stage, increasing safety and
decreasing, at least theoretically, the impact of future launches on low Earth
orbit.
This is not a totally new concept.
The Americans, Japanese, and French have explored use of residual fuel for
controlled re-entry of the 2nd stages of the Delta IV, HII-B,
and Ariane 5 respectively. However, since these rockets use, liquid
hydrogen-oxygen (LOX/LH2) as fuel/oxidizer, it is less problematic to re-start
the main liquid propulsion engine. Russian space launchers use instead either
high boiling toxic fuel such as UDMH (Proton-M, Rokot) or kerosene (Angara,
Zenit, Soyuz). Ensuring the restartability of the main engine with such fuels
is more problematic and this is why Trushlyakov started developing the ADOS
concept in the first place.
The research, now in the design
phase, is being conducted with Roscosmos and Samara Space Centre, for the
improvement of Soyuz 2.1B, a green and lighter version of the Soyuz-2 family.
According to the results so far, the ADOS system can produce a ∆V of 370 m/s
for the 1st stage and 500 m/s for the 2nd stage using
just the remnant propellant in the tanks
Although so far the initiative has
been Russian in origin, Trushlyakov emphasizes the need for an international
effort from every country involved in space. He and his team are ready to work
with international teams to develop similar system for other launchers,
whenever they demonstrate interest.
ADOS addresses the need to keep
near-Earth space free of new debris. But since Earth orbit has been already
polluted with tons of debris since 1957, mitigation might not be the only
approach to address the space debris issue. In the third and final installment
in this series, we will learn of the steps Trushlyakov is taking to meet this
looming hazard and Shalaj’s prognosis for the Russian Space industry.
New ESA Safety Standard Now Available
The European Space Agency (ESA) has just issued Safety System Engineering: Safety Technical Requirements for Human Rated Space Systems, a new human spaceflight standard. Chapter 1 describes the scope of the document:
New ESA Safety Standard Now Available
The European Space Agency (ESA) has just issued Safety System Engineering: Safety Technical Requirements for Human Rated Space Systems, a new human spaceflight standard. Chapter 1 describes the scope of the document:
"This document establishes the requirements applicable to the development and operations of human‐rated space systems for ESA human spaceflight missions. These requirements are intended to protect the public, the ground and flight personnel, the space system, any interfacing system, public and private property and the environment from hazards associated with flight operations, and with ground operations with fight personnel on‐board the system (e.g. launch pad operations)."
Open publication -
Other European Document resources on Human Spaceflight |
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