Challenger Tragedy: Presidential Report Concluded
Recommendations of the Presidential Commission
The Commission has conducted an extensive investigation of the
Challenger accident to determine the probable cause and necessary
corrective actions. Based on the findings and determinations of its
investigation, the Commission has unanimously adopted recommendations to
help assure the return to safe flight.
The Commission urges that the Administrator of NASA submit, one year
from now, a report to the President on the progress that NASA has made in
effecting the Commission's recommendations set forth below:
The faulty Solid Rocket Motor joint and seal must be changed. This
could be a new design eliminating the joint or a redesign of the current
joint and seal. No design options should be prematurely precluded because
of schedule, cost or reliance on existing hardware. All Solid Rocket Motor
joints should satisfy the following requirements:
The joints should be fully understood, tested and verified.
The integrity of the structure and of the seals of all joints should be
not less than that of the case walls throughout the design envelope.
The integrity of the joints should be insensitive to: --Dimensional
tolerances. --Transportation and handling. --Assembly procedures.
--Inspection and test procedures. --Environmental effects. --Internal case
operating pressure. --Recovery and reuse effects. --Flight and water
The certification of the new design should include: --Tests which
duplicate the actual launch configuration as closely as possible. --Tests
over the full range of operating conditions, including temperature.
Full consideration should be given to conducting static firings of the
exact flight configuration in a vertical attitude.
The Administrator of NASA should request the National Research Council
to form an independent Solid Rocket Motor design oversight committee to
implement the Commission's design recommendations and oversee the design
effort. This committee should:
Review and evaluate certification requirements. Provide technical
oversight of the design, test program and certification. Report to the
Administrator of NASA on the adequacy of the design and make appropriate
II SHUTTLE MANAGEMENT STRUCTURE
The Shuttle Program Structure should be reviewed. The project managers
for the various elements of the Shuttle program felt more accountable to
their center management than to the Shuttle program organization. Shuttle
element funding, work package definition, and vital program information
frequently bypass the National STS (Shuttle) Program Manager.
A redefinition of the Program Manager's responsibility is essential.
This redefinition should give the Program Manager the requisite authority
for all ongoing STS operations. Program funding and all Shuttle Program
work at the centers should be placed clearly under the Program Manager's
ASTRONAUTS IN MANAGEMENT
The Commission observes that there appears to be a departure from the
philosophy of the 1960s and 1970s relating to the use of astronauts in
management positions. These individuals brought to their positions flight
experience and a keen appreciation of operations and flight safety.
NASA should encourage the transition of qualified astronauts into
agency management positions.
The function of the Flight Crew Operations director should be elevated
in the NASA organization structure.
SHUTTLE SAFETY PANEL
NASA should establish an STS Safety Advisory Panel reporting to the STS
Program Manager. The Charter of this panel should include Shuttle
operational issues, launch commit criteria, flight rules, flight readiness
and risk management. The panel should include representation from the
safety organization, mission operations, and the astronaut office.
III CRITICALITY REVIEW AND HAZARD ANALYSIS
NASA and the primary Shuttle contractors should review all Criticality
1, 1R, 2, and 2R items and hazard analyses. This review should identify
those items that must be improved prior to flight to ensure mission
safety. An Audit Panel, appointed by the National Research Council, should
verify the adequacy of the effort and report directly to the Administrator
IV SAFETY ORGANIZATION
NASA should establish an Office of Safety, Reliability and Quality
Assurance to be headed by an Associate administrator, reporting directly
to the NASA Administrator. It would have direct authority for safety,
reliability, and quality assurance throughout the agency. The office
should be assigned the work force to ensure adequate oversight of its
functions and should be independent of other NASA functional and program
The responsibilities of this office should include:
The safety, reliability and quality assurance functions as they relate
to all NASA activities and programs.
Direction of reporting and documentation of problems, problem
resolution and trends associated with flight safety.
V IMPROVED COMMUNICATIONS
The Commission found that Marshall Space Flight Center project
managers, because of a tendency at Marshall to management isolation,
failed to provide full and timely information bearing on the safety of
flight 51-L to other vital elements of Shuttle program management.
NASA should take energetic steps to eliminate this tendency at Marshall
Space Flight Center, whether by changes of personnel, organization,
indoctrination or all three.
A policy should be developed which governs the imposition and removal
of Shuttle launch constraints.
Flight Readiness Reviews and Mission Management Team meetings should be
The flight crew commander, or a designated representative, should
attend the Flight Readiness Review, participate in acceptance of the
vehicle for flight, and certify that the crew is properly prepared for
VI LANDING SAFETY
NASA must take actions to improve landing safety.
The tire, brake and nosewheel steering systems must be improved. These
systems do not have sufficient safety margin, particularly at abort
The specific conditions under which planned landings at Kennedy would
be acceptable should be determined. Criteria must be established for
tires, brakes and nosewheel steering. Until the systems meet those
criteria in high fidelity testing that is verified at Edwards, landing at
Kennedy should not be planned.
Committing to a specific landing site requires that landing area
weather be forecast more than an hour in advance. During unpredictable
weather periods at Kennedy, program officials should plan on Edwards
landings. Increased landings at Edwards may necessitate a dual ferry
VII LAUNCH ABORT AND CREW ESCAPE
The Shuttle program management considered first-stage abort options and
crew escape options several times during the history of the program, but
because of limited utility, technical infeasibility, or program cost and
schedule, no systems were implemented. The Commission recommends that
Make all efforts to provide a crew escape system for use during
controlled gliding flight.
Make every effort to increase the range of flight conditions under
which an emergency runway landing can be successfully conducted in the
event that two or three main engines fail early in ascent.
VIII FLIGHT RATE
The nation's reliance on the Shuttle as its principal space launch
capability created a relentless pressure on NASA to increase the flight
rate. Such reliance on a single launch capability should be avoided in the
NASA must establish a flight rate that is consistent with its
resources. A firm payload assignment policy should be established. The
policy should include rigorous controls on cargo manifest changes to limit
the pressures such changes exert on schedules and crew training.
IX MAINTENANCE SAFEGUARDS
Installation, test, and maintenance procedures must be especially
rigorous for Space Shuttle items designated Criticality 1. NASA should
establish a system of analyzing and reporting performance trends of such
Maintenance procedures for such items should be specified in the
Critical Items List, especially for those such as the liquid-fueled main
engines, which require unstinting maintenance and overhaul.
With regard to the Orbiters, NASA should:
- Develop and execute a comprehensive maintenance inspection plan.
- Perform periodic structural inspections when scheduled and not
permit them to be waived.
- Restore and support the maintenance and spare parts programs, and
stop the practice of removing parts from one Orbiter to supply
The Commission urges that NASA continue to receive the support of the
Administration and the nation. The agency constitutes a national resource
that plays a critical role in space exploration and development. It also
provides a symbol of national pride and technological leadership.
The Commission applauds NASA's spectacular achievements of the past and
anticipates impressive achievements to come. The findings and
recommendations presented in this report are intended to contribute to the
future NASA successes that the nation both expects and requires as the
21st century approaches.
NASA Actions To Implement Commission
(Source: Actions to Implement the Recommendations of The Presidential
Commission on the Space Shuttle Challenger Accident, Executive Summary,
July 14, 1986, NASA Headquarters)
On June 13, 1986, the President directed NASA to implement, as soon as
possible, the recommendations of the Presidential Commission on the Space
Shuttle Challenger Accident. The President requested that NASA report,
within 30 days, how and when the recommendations will be implemented,
including milestones by which progress can be measured.
In the months since the Challenger accident, the NASA team has spent
many hours in support of the Presidential Commission on the Space Shuttle
Challenger Accident and in planning for a return of the Shuttle to safe
flight status. Chairman William P. Rogers and the other members of the
Commission have rendered the Nation and NASA an exceptional service. The
work of the Commission was extremely thorough and comprehensive. NASA
agrees with the Commission's recommendations and is vigorously pursuing
the actions required to implement and comply with them.
As a result of the efforts in support of the Commission, many of the
actions required to safely return the Space Shuttle to flight status have
been under way since March. On March 24, 1986, the Associate Administrator
for Space Flight outlined a comprehensive strategy, and defined major
actions, for safely returning to flight status. The March 24 memorandum
(Commission Activities: An Overview) provided guidance on the following
actions required prior to next flight, first flight/first year
operations, and development of sustainable safe flight rate.
The Commission report was submitted to the President on June 9, 1986.
Since that time, NASA has taken additional actions and provided direction
required to comply with the Commission's recommendations.
The NASA Administrator and the Associate Administrator for Space Flight
will participate in the key management decisions required for implementing
the Commission recommendations and for returning the Space Shuttle to
flight status. NASA will report to the President on the status of the
implementation program in June 1987.
The Commission report included nine recommendations, and a summary of
the implementation status for each is provided:
RECOMMENDATION I Solid Rocket Motor Design:
On March 24, 1986, the Marshall Space Flight Center (MSFC) was directed
to form a Solid Rocket Motor (SSRM) joint redesign team to include
participation from MSFC and other NASA centers as well as individuals from
outside NASA. The team includes personnel from Johnson Space Center,
Kennedy Space Center, Langley Research Center, industry, and the Astronaut
Office. To assist the redesign team, an expert advisory panel was
appointed which includes 12 people with six coming from outside NASA.
The team has evaluated several design alternatives, and analysis and
testing are in progress to determine the preferred approaches which
minimize hardware redesign. To ensure adequate program contingency in this
effort, the redesign team will also develop, at least through concept
definition, a totally new design which does not utilize existing hardware.
The design verification and certification program will be emphasized and
will include tests which duplicate the actual launch loads as closely as
feasible and provide for tests over the full range of operating
conditions. The verification effort includes a trade study which has been
under way for several weeks to determine the preferred test orientation
(vertical or horizontal) of the full-scale motor firings. The Solid Rocket
Motor redesign and certification schedule is under review to fully
understand and plan for the implementation of the design solutions as they
are finalized and assessed. The schedule will be reassessed after the SRM
Preliminary Design Review in September 1986. At this time it appears that
the first launch will not occur prior to the first quarter of 1988.
Independent Oversight: In accordance with the Commission's
recommendation, the National Research Council (NRC) has established an
Independent Oversight Group chaired by Dr. H. Guyford Stever and reporting
to the NASA Administrator. The NRC Oversight Group has been briefed on
Shuttle system requirements, implementation, and control; Solid Rocket
Motor background; and candidate modifications. The group has established a
near-term plan that includes briefings and visits to review inflight
loads; assembly processing; redesign status; and other solid rocket motor
designs, including participation in the Solid Rocket Motor preliminary
design review in September 1986.
RECOMMENDATION II Shuttle Management Structure:
The Administrator has appointed General Sam Phillips, who served as
Apollo Program Director, to study every aspect of how NASA manages its
programs, including relationships between various field centers and NASA
Headquarters. General Phillips has broad authority from the Administrator
to explore every aspect of NASA organization, management and procedures.
His activities will include a review of the Space Shuttle management
On June 25, 1986, Astronaut Robert Crippen was directed to form a
fact-finding group to assess the Space Shuttle management structure. The
group will report recommendations to the Associate Administrator for Space
Flight by August 15, 1986. Specifically, this group will address the roles
and responsibilities of the Space Shuttle Program Manager to assure that
the position has the authority commensurate with its responsibilities. In
addition, roles and responsibilities at all levels of program management
will be reviewed to specify the relationship between the program
organization and the field center organizations. The results of this study
will be reviewed with General Phillips and the Administrator with a
decision on implementation of the recommendations by October 1, 1986.
Astronauts in Management Rear Admiral Richard Truly, a former
astronaut, has been appointed as Associate Administrator for the Office of
Space Flight. Several active astronauts are currently serving in
management positions in the agency. The Crippen group will address means
to stimulate the transition of astronauts into other management positions.
It will also determine the appropriate position for the Flight Crew
Operations Directorate within the NASA organizational structure.
Shuttle Safety Panel A Shuttle Safety Panel will be established by the
Associate Administrator for Space Flight not later than September 1, 1986,
with direct access to the Space Shuttle Program Manager. This date allows
time to determine the structure and function of this panel, including an
assessment of its relationship to the newly formed Office of Safety,
Reliability, and Quality Assurance, and to the existing Aerospace Safety
RECOMMENDATION III Critical Item Review and Hazard Analysis
On March 13, 1986, NASA initiated a complete review of all Space
Shuttle program failure modes and effects analyses (FEMEA's) and
associated critical item lists (CIL's). Each Space Shuttle project element
and associated prime contractor is conducting separate comprehensive
reviews which will culminate in a program-wide review with the Space
Shuttle program have been assigned as formal members of each of these
review teams. All Criticality 1 and 1R critical item waivers have been
cancelled. The teams are required to reassess and resubmit waivers in
categories recommended for continued program applicability. Items which
cannot be revalidated will be redesigned, qualified, and certified for
flight. All Criticality 2 and 3 CIL's are being reviewed for reacceptance
and proper categorization. This activity will culminate in a comprehensive
final review with NASA Headquarters beginning in March 1987.
As recommended by the Commission, the National Research Council has
agreed to form an Independent Audit Panel, reporting to the NASA
Administrator, to verify the adequacy of this effort.
RECOMMENDATION IV Safety Organization
The NASA Administrator announced the appointment of Mr. George A.
Rodney to the position of Associate Administrator for Safety, Reliability,
and Quality Assurance on July 8, 1986. The responsibilities of this office
will include the oversight of safety, reliability, and quality assurance
functions related to all NASA activities and programs and the
implementation of a system for anomaly documentation and resolution to
include a trend analysis program. One of the first activities to be
undertaken by the new Associate Administrator will be an assessment of the
resources including workforce required to ensure adequate execution of the
safety organization functions. In addition, the new Associate
Administrator will assure appropriate interfaces between the functions of
the new safety organization and the Shuttle Safety Panel which will be
established in response to the Commission Recommendation II.
Improved Communications On June 25, 1986, Astronaut Robert Crippen was
directed to form a team to develop plans and recommended policies for the
Implementation of effective management communications at all levels.
Standardization of the imposition and removal of STS launch constraints
and other operational constraints.
Conduct of Flight Readiness Review and Mission Management Team
meetings, including requirements for documentation and flight crew
Since this recommendation is closely linked with the recommendation on
Shuttle management structure, the study team will incorporate the plan for
improved communications with that for management restructure.
This review of effective communications will consider the activities
and information flow at NASA Headquarters and the field centers which
support the Shuttle program. The study team will present findings and
recommendations to the Associate Administrator for Space Flight by August
RECOMMENDATION VI Landing Safety
A Landing Safety Team has been established to review and implement the
Commission's findings and recommendations on landing safety. All Shuttle
hardware and systems are undergoing design reviews to insure compliance
with the specifications and safety concerns. The tires, brakes, and nose
wheel steering system are included in this activity, and funding for a new
carbon brakes system has been approved. Runway surface tests and landing
aid requirement reviews had been under way for some time prior to the
accident and are continuing. Landing aid implementation will be complete
by July 1987. The interim brake system will be delivered by August 1987.
Improved methods of local weather forecasting and weather-related support
are being developed. Until the Shuttle program has demonstrated
satisfactory safety margins through high fidelity testing and during
actual landings at Edwards Air Force Base, the Kennedy Space Center
landing site will not be used for nominal end-of-mission landings. Dual
Orbiter ferry capability has been an issue for some time and will be
thoroughly considered during the upcoming months.
RECOMMENDATION VII Launch Abort and Crew Escape
On April 7, 1986, NASA initiated a Shuttle Crew Egress and Escape
review. The scope of this analysis includes egress and escape capabilities
from launch through landing and will provide analyses, concepts,
feasibility assessments, cost, and schedules for pad abort, bailout,
ejection systems, water landings, and powered flight separation. This
review will specifically assess options for crew escape during controlled
gliding flight and options for extending the intact abort flight envelope
to include failure of 2 or 3 main engines during the early ascent phase.
In conjunction with this activity, a Launch Abort Reassessment Team was
established to review all launch and launch abort rules to ensure that
launch commit criteria, flight rules, range safety systems and procedures,
landing aids, runway configurations and lengths, performance versus abort
exposure, abort and end-of-mission landing weights, runway surfaces, and
other landing-related capabilities provide the proper margin of safety to
the vehicle and crew. Crew escape and launch abort studies will be
complete on October 1, 1986, with an implementation decision in December
RECOMMENDATION VIII Flight Rate
In March 1986 NASA established a Flight Rate Capability Working Group.
Two flight rate capability studies are under way:
(1) a study of capabilities and constraints which govern the Shuttle
processing flows at the Kennedy Space Center and
(2) a study by the Johnson Space Center to assess the impact of flight
specific crew training and software delivery/certification on flight
The working group will present flight rate recommendations to the
Office of Space Flight by August 15, 1986. Other collateral studies are
still in progress which address Presidential Commission recommendations
related to spares provisioning, maintenance, and structural inspection.
This effort will also consider the National Research Council independent
review of flight rate which is under way as a result of a Congressional
NASA strongly supports a mixed fleet to satisfy launch requirements and
actions to revitalize the United States expendable launch vehicle
Additionally, a new cargo manifest policy is being formulated by NASA
Headquarters which will establish manifest ground rules and impose
constraints to late changes. Manifest control policy recommendations will
be completed in November 1986.
RECOMMENDATION IX Maintenance Safeguards
A Maintenance Safeguards Team has been established to develop a
comprehensive plan for defining and implementing actions to comply with
the Commission recommendations concerning maintenance activities. A
Maintenance Plan is being prepared to ensure that uniform maintenance
requirements are imposed on all elements of the Space Shuttle program.
This plan will define the structure that will be used to document (1)
hardware inspections and schedules, (2) planned maintenance activities,
(3) Maintenance procedures configuration control, and (4) Maintenance
The plan will also define organizational responsibilities, reporting,
and control requirements for Space Shuttle maintenance activities. The
maintenance plan will be completed by September 30, 1986.
A number of other activities are underway which will contribute to a
return to safe flight and strengthening the NASA organization. A Space
Shuttle Design Requirements Review Team headed by the Space Shuttle
Systems Integration Office at Johnson Space Center has been assigned to
review all Shuttle design requirements and associated technical
verification. The team will focus on each Shuttle project element and on
total Space Shuttle system design requirements. This activity will
culminate in a Space Shuttle Incremental Design Certification Review
approximately 3 months prior to the next Space Shuttle Launch.
In consideration of the number, complexity, and interrelationships
between the many activities leading to the next flight, the Space Shuttle
Program Manager at Johnson Space Center has initiated a series of formal
Program Management Reviews for the Space Shuttle program. These reviews
are structured to be regular face-to-face discussions involving the
managers of all major Space Shuttle program activities. Specific subjects
to be discussed at each meeting will focus on progress, schedules, and
actions associated with each of the major program review activities and
will be tailored directly to current program activity for the time period
involved. The first of these meetings was held at Marshall Space Flight
Center on May 5-6, 1986, with the second at Kennedy Space Center on June
25, 1986. Follow-on reviews will be held approximately every 6 weeks.
Results of these reviews will be reported to the Associate Administrator
for Space Flight and to the NASA Administrator.
On June 19, 1986, the NASA Administrator announced termination of the
development of the Centaur upper stage for use aboard the Space Shuttle.
Use of the Centaur upper stage was planned for NASA planetary spacecraft
launches as well as for certain national security satellite launches.
Majority safety reviews of the Centaur system were under way at the time
of the Challenger accident, and these reviews were intensified in recent
months to determine if the program should be continued. The final decision
to terminate the Centaur stage for use with the Shuttle was made on the
basis that even following certain modifications identified by the ongoing
reviews, the resultant stage would not meet safety criteria being applied
to other cargo or elements of the Space Shuttle System. NASA has initiated
efforts to examine other launch vehicle alternatives for the major NASA
planetary and scientific payloads which were scheduled to utilize the
Centaur upper stage. NASA is providing assistance to the Department of
Defense as it examines alternatives for those national security missions
which had planned to use the Shuttle/Centaur.
The NASA Administrator has announced a number of Space Station
organizational and management structural actions designed to strengthen
technical and management capabilities in preparation for moving into the
development phase of the Space Station program. The decision to create the
new structure is the result of recommendations made to the Administrator
by a committee, headed by General Phillips, which is conducting a long
range assessment of NASA's overall capabilities and requirements.
Finally, NASA is developing plans for increased staffing in critical
areas and is working closely with the Office of Personnel Management to
develop a NASA specific proposal which would provide for needed changes to
the NASA personnel management system to strengthen our ability to attract,
retain, and motivate the quality workforce required to conduct the NASA
[END OF REPORT]