Douglas Isbell/Don Savage
Headquarters, Washington, DC Nov. 10, 1999
(Phone: 202/358-1547) Embargoed until 2 p.m. EST
RELEASE: 99-134
MARS CLIMATE ORBITER FAILURE BOARD RELEASES REPORT, NUMEROUS NASA ACTIONS UNDERWAY IN RESPONSE
Wide-ranging managerial and technical actions are underway at
NASA’s Jet Propulsion Laboratory, Pasadena, CA, in response to the
loss of the Mars Climate Orbiter and the initial findings of the
mission failure investigation board, whose first report was
released today.
Focused on the upcoming landing of NASA’s Mars Polar Lander,
these actions include: a newly assigned senior management leader,
freshly reviewed and augmented work plans, detailed fault tree
analyses for pending mission events, daily telecons to evaluate
technical progress and plan work yet to be done, increased
availability of the Deep Space Network for communications with the
spacecraft, and independent peer review of all operational and
contingency procedures.
The board recognizes that mistakes occur on spacecraft
projects, the report said. However, sufficient processes are
usually in place on projects to catch these mistakes before they
become critical to mission success. Unfortunately for MCO, the
root cause was not caught by the processes in place in the MCO
project.
“We have mobilized the very best talent at the Jet Propulsion
Laboratory (JPL) to respond thoroughly to the specific
recommendations in the board’s report and the other areas of
concern highlighted by the board,” said Dr. Edward Stone, director
of JPL. “Special attention is being directed at navigation and
propulsion issues, and a fully independent ‘red team’ will review
and approve the closure of all subsequent actions. We are
committed to doing whatever it takes to maximize the prospects for
a successful landing on Mars on Dec. 3.”
The failure board’s first report identifies eight
contributing factors that led directly or indirectly to the loss
of the spacecraft. These contributing causes include inadequate
consideration of the entire mission and its post-launch operation
as a total system, inconsistent communications and training within
the project, and lack of complete end-to-end verification of
navigation software and related computer models.
“The ‘root cause’ of the loss of the spacecraft was the
failed translation of English units into metric units in a segment
of ground-based, navigation-related mission software, as NASA has
previously announced,” said Arthur Stephenson, chairman of the
Mars Climate Orbiter Mission Failure Investigation Board. “The
failure review board has identified other significant factors that
allowed this error to be born, and then let it linger and
propagate to the point where it resulted in a major error in our
understanding of the spacecraftÕs path as it approached Mars.
“Based on these findings, we have communicated a range of
recommendations and associated observations to the team planning
the landing of the Polar Lander, and the team has given these
recommendations some serious attention,” said Stephenson, director
of NASA’s Marshall Space Flight Center, Huntsville, AL.
The board’s report cites the following contributing factors:
* errors went undetected within ground-based computer models of
how small thruster firings on the spacecraft were predicted and
then carried out on the spacecraft during its interplanetary trip
to Mars
* the operational navigation team was not fully informed on the
details of the way that Mars Climate Orbiter was pointed in space,
as compared to the earlier Mars Global Surveyor mission
* a final, optional engine firing to raise the spacecraft’s path
relative to Mars before its arrival was considered but not
performed for several interdependent reasons
* the systems engineering function within the project that is
supposed to track and double-check all interconnected aspects of
the mission was not robust enough, exacerbated by the first-time
handover of a Mars-bound spacecraft from a group that constructed
it and launched it to a new, multi-mission operations team
* some communications channels among project engineering groups
were too informal
* the small mission navigation team was oversubscribed and its
work did not receive peer review by independent experts
* personnel were not trained sufficiently in areas such as the
relationship between the operation of the mission and its detailed
navigational characteristics, or the process of filing formal
anomaly reports
* the process to verify and validate certain engineering
requirements and technical interfaces between some project groups,
and between the project and its prime mission contractor, was
inadequate
The failure board will now proceed with its work on a second
report due by Feb. 1, 2000, which will address broader lessons
learned and recommendations to improve NASA processes to reduce
the probability of similar incidents in the future.
Mars Climate Orbiter and its sister mission, the Mars Polar
Lander, are part of a series of missions in a long-term program of
Mars exploration managed by the Jet Propulsion Laboratory for
NASA’s Office of Space Science, Washington, DC. JPL’s industrial
partner is Lockheed Martin Astronautics, Denver, CO. JPL is a
division of the California Institute of Technology, Pasadena, CA.
The Board’s report is available on-line at:
ftp://ftp.hq.nasa.gov/pub/pao/reports/1999/MCO_report.pdf
Charts used in the briefing today are available on-line at:
ftp://ftp.hq.nasa.gov/pub/pao/reports/1999/MCO_charts.pdf
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