Versus Redesigned Field Joint
The SRM field-joint metal parts, internal case insulation and seals
were redesigned and a weather protection system was added.
Versus Redesigned SRM Case-to-Nozzle Joint
The SRM case-to nozzle joint has been redesigned to satisfy the
same requirements imposed upon the case field joint.
The internal joints of the nozzle metal parts have been redesigned.
Minor modifications were made in the case factory joints.
The motor propellant forward transition region was recontoured.
Several minor modifications were incorporated into the ignition
The ground support equipment has been redesigned.
Continuing these analyses will ensure that the design integrity
and system compatibility adhere to design requirements and operational
The verification program encompasses the following program phases:
development, certification, acceptance, preflight checkout, flight
The Shuttle 51-L and Titan 34D-9 vehicle failures, both of which
occurred in 1986, resulted in major reassessments of each vehicle's
design, processing, inspection and operations.
To provide additional program confidence, both near- and long-term
contingency planning was implemented.
At the request of the NASA administrator, the National Research
Council established an Independent Oversight Panel.