| Douglas Isbell/Don Savage Headquarters, Washington, DC Nov. 10, 1999 (Phone: 202/358-1547) |
Nov. 10, 1999 |
RELEASE: H99-134
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 spacecraft's 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