1、Lessons Learned Entry: 0011Lesson Info:a71 Lesson Number: 0011a71 Lesson Date: 1991-06-17a71 Submitting Organization: JSCa71 Submitted by: D. CarrollSubject: Addition of X-Rays to Screen for Defects (Embedded Wood Chips) in Shuttle Orbiter Tires that Visual and Holographic Techniques May Not Detect
2、Description of Driving Event: Inspection of the Nose Landing Gear (NLG) tire revealed a 1/4“ cut which appeared to have a small piece of wood embedded in it. The investigation of the tire included: (1) X-Rays that verified the position and size of the wood chip; (2) review of the standard holography
3、 inspection data that verified the technique failed to reveal the defect; and (3) sectioning of the tire to determine the origin of the chip. The wood chip came from the cart used to transport the tread gum rubber to the tire builder and was built into the tire. The wood chip became visible only aft
4、er inflation. All existing orbiter tires were X-Rayed to screen for similar defects and tire inspection techniques were changed to include X-Rays. The wood chip caused a delamination sufficient to produce a tire failure under some worst case, but feasible, landing scenarios (maximum permissible cros
5、s wind at KSC). However, the other NLG tire would have supported the orbiter following this failure.Lesson(s) Learned: Visual and holographic inspections of critical use tires can fail to reveal defects such as embedded wood chips and lead to tire failure. X-Rays may be required.Recommendation(s): X
6、Rays of shuttle orbiter tires were added as an inspection technique. Existing orbiter tires were X-Rayed to screen for similar defects.Evidence of Recurrence Control Effectiveness: N/AProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Documents Related
7、 to Lesson: N/AMission Directorate(s): a71 Exploration Systemsa71 Space Operationsa71 Aeronautics ResearchAdditional Key Phrase(s): a71 Aircrafta71 Configuration Managementa71 Facilitiesa71 Flight Operationsa71 Flight Equipmenta71 Ground Operationsa71 Ground Equipmenta71 Hardwarea71 Launch Processa7
8、1 Launch Vehiclea71 Parts Materials & ProcessesAdditional Info: Approval Info: a71 Approval Date: 1993-09-27a71 Approval Name: Ron Montaguea71 Approval Organization: JSC/NS3a71 Approval Phone Number: 281-483-8576Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
