Description of Driving Event:
Line-Replaceable Unit (LRU) Restoration and Upgrading
Lesson(s) Learned:
Support of the Space Shuttle fleet with operational spares has been maintained by the effective efforts of the logistics function. While spares support has been adequate for the current flight rate, any increase in flight rate might not be supportable.
Recommendation(s):
Although NASA has established programs for dealing with suppliers and bringing additional component overhaul "in house," efforts in these areas need to be continuously reexamined to speed up the restoration and upgrading of line-replaceable units. Such efforts are especially needed to eliminate "dead" time while units are awaiting restoration.
Evidence of Recurrence Control Effectiveness:
The Space Shuttle Program concurs with the ASAP concerns for the availability of line replaceable units (LRU's). Logistics monitors LRU spares posture through the probability of sufficiency calculations within the LRU data system. This system can be programmed to determine spares requirements for various flight rates. At this time, an appreciable increase in flight rate would be required to jeopardize supporting the Space Shuttle Program with most of the current LRU's. The Program has been proactive in upgrading LRU's where the most pressing fleet support concerns exist. The following upgrades are in progress:
- The air data transducer assembly is being replaced by the advanced air data transducers.
- The master events controller is being replaced by the advanced master events controller.
- The Global Positioning System is being installed in the orbiters at the orbiter major modification. This could potentially eliminate a number of LRU's in the displays and controls system and tactical air navigation system.
- New shop replaceable units were purchased to repair the Microwave Scanning Beam Land Station decoders. This decreases turnaround time and increases reliability of the units.
- Solid state recorders are being considered as replacements for the operations and payload recorders. This effort is presently in the design definition phase.
Additionally, through the use of industrial engineering principles and work teams, Logistics has taken action to reduce the NASA Shuttle Logistics Depot (NSLD) backlog and increase output for fiscal year 1998. To date, backlog has decreased 8 percent since October 1 by increasing output. These efforts are aimed at providing better support at the current flight rate but are also the type of efforts that will allow higher flight rates in the future.
Documents Related to Lesson:
N/A
Mission Directorate(s):
- Space Operations
- Exploration Systems
Additional Key Phrase(s):
- Aerospace Safety Advisory Panel
- Logistics
- Parts Materials & Processes
- Policy & Planning
- Risk Management/Assessment
- Safety & Mission Assurance
Additional Info:
|
