REG NASA-LLIS-1582-2005 Lessons Learned - Altered Explosive Initiator Causes Damage - 4-8-05.pdf

1、Lessons Learned Entry: 1582Lesson Info:a71 Lesson Number: 1582a71 Lesson Date: 2005-08-31a71 Submitting Organization: KSCa71 Authored by: John W JambaSubject: Altered Explosive Initiator Causes Damage - 4-8-05 Abstract: In August of 2003, a NASA Standard Initiator (NSI) test program was started. Fou

2、r NSIs were modified to induce ejection, or in other words, a system failure in the test chamber. Three items were tested and the test was declared over. The fourth altered NSI was returned to the explosive magazine to support possible future testing. In April 2005, a Pressure Verification Test was

3、started with NSIs to verify the pressure in the test articles to support Return to Flight. The first article selected was the altered NSI left over from the previous test. When fired, it was ejected from the chamber and caused the damage. Description of Driving Event: There is no requirement, policy

4、 or procedure governing the use or disposition of altered ordnance. The original test program, 90PLN-043 Engineering Plan (Effects of Aft Separation Bolt NSI Ejection on SRB Aft Strut External Tank Clevis End Energy Absorber) did not address the disposition of unexpended ordnance. Work Authorization

5、 Documents (WAD) do not contain closed-loop accountability for left-over, unused ordnance. Neither the unused unexpended ordnance nor the ammo can in which it was stored were appropriately marked to indicate the altered state of the NSI. Also, the altered condition of the NSI was not easily detectab

6、le. A First Article Review was not performed per Shuttle Engineering Directive T35R6. The CAIB NSI Ejection Tests were performed in August 2003 using a strut assembly with clevis installed, which may have given the technicians and engineers a false sense of altered ordnance acceptance. The test cond

7、ucted within the struts masked the power of an uncontrolled ejecting NSI. Lesson(s) Learned: When explosive hardware is configured outside its intended design after a test program has finished, Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-provide

8、procedures and policies that will return it to its original configuration, fire it as part of the test plan or send it to Explosives Ordnance Disposal (EOD). If temporary storage is required, ensure that a policy or procedure is in existence that requires the commodity to be properly marked, segrega

9、ted and stored. Also, the ammo can or storage container in which it is stored has to be properly labeled. Include a First Article Review before the test starts. Recommendation(s): Develop and implement procedures to return explosive devices to their original configuration, fire it as part of a test

10、plan or send it to Explosives Ordnance Disposal. Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: N/AMission Directorate(s): a71 Exploration Systemsa71 Sciencea71 Aeronautics Researcha71 Space OperationsAdditional Key Phrase(s): a71 Accident Investigationa71 Configuratio

11、n Managementa71 Energetic Materials - Explosive/Propellant/Pyrotechnica71 Explosives Handlinga71 Launch Processa71 Packaginga71 Handlinga71 Storagea71 Risk Management/Assessmenta71 Safety & Mission Assurancea71 Test & VerificationAdditional Info: Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Approval Info: a71 Approval Date: 2006-12-04a71 Approval Name: ghendersona71 Approval Organization: HQProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-