1、Public Lessons Learned Entry: 4456 Lesson Info: Lesson Number: 4456 Lesson Date: 2010-06-18 Submitting Organization: KSC Submitted by: Annette Pitt Subject: Ice Detection Camera (IDC) Close Call Abstract: Ground support equipment, facilities, and shop aids all have defined NASA design requirements a
2、nd processes. All hardware, whether Commercial Off The Shelf (COTS) or prototype, used in proximity of a space vehicle require the performance of all design, operation, and training verification procedures. Description of Driving Event: On February 26, 2010, at 2330 hours, on Complex 39 A Mobile Lau
3、nch Platform 0 level, the STS-130 Final Inspection Team (FIT) began their T3-hour walk down. The operator, a NASA FIT engineer, started to configure, pressurize, and power up the MacDonald, Detwiller, and Associates (MDA) Prototype Ice Detection Camera (IDC). Provided by IHSNot for ResaleNo reproduc
4、tion or networking permitted without license from IHS-,-,-Figure 1: OThe operatstage reguadjusting tverall IDC Conor reported thalator gauge valvhe IDC rapid-exfiguration t the initial GN2e and observechange valve asupply cylinded a pressure innd completing r pressure readcrease to 10 psthe power-up
5、 seing was 2,900 pi (the nominal oquence, he obsi. He then turnperational presserved an immeed the IDC sinsure setting). Adiate loss of gle-fter Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-system prepower, cloWhen he rsecured thand pneumcorner, w
6、hgauge but as a “loud Figure 2: SLesson(s)The IDC wVolume X;1. Tssure, with thesed the GN2 sueturned, he moe spare GN2 boatic connectionere he connectdid not touch owhine and a poudden PressurLearned: as not designedSW-E-0002; Khe IDC purge cGN2 supply cypply cylinder vaved the IDC outttle. But beca
7、us. Upon arrivaled the GN2 gasr adjust it. He op.” The panel ge Change Shator fabricated iSC-STD-E-0002omponents welinder and presslve, and proceeside the west ese the FIT was at the 255 levebottle. While mpened the GN2lass had shattetered Display Pn accordance wE; and KSC-Ere not designedure regula
8、tor rded to the padlevator at the Fpreparing to mol, the operator aking the connsupply cylinderred (see figure anel ith the following-165E. to prevent oveeading 0 psi. Hesurface to retriixed Surface Stve to the 255 rolled the IDC fection, he lookevalve slightly a2). NASA designrpressurization,then t
9、urned ofeve a spare GNructure (FSS) 9level, he did norom the elevatod at the single-nd then heard wrequirements: which caused f the electrical 2 cylinder. 5 level and t complete the gr to the southwstage regulatorhat he describNSTS 07700, system failure. as est ed Provided by IHSNot for ResaleNo rep
10、roduction or networking permitted without license from IHS-,-,-2. Instead of a Bepco enclosure pressure control valve, a Bepco control panel rapid-exchange valve was used to control GN2 system purge. This allowed the rapid release of overpressure, which in turn caused the system to fail. 3. The IDC
11、single-stage regulator was found to have vibrated open, causing the inlet pressure to increase (creep) to 50 psi. The nominal operational pressure setting is 10 psi. This increase in the inlet pressure setting allowed the system to become overpressurized and caused the system to fail. 4. The IDC cam
12、era head enclosure lid was not sealed properly because of ground wire interference, which caused a differential in system pressure between enclosures. 5. The bottom clip on the IDC camera battery, power supply, and power supply enclosure were seated but did not catch the enclosure door, which contri
13、buted to system purge leakage. 6. NASA lab personnel completed measurement testing before the ICD was put into operational use. However, purge system operation and functional checkout were not performed, which prevented detection of system overpressurization before operational use. 7. The current op
14、erational procedure, MDA Prototype Ice Detection Camera User Manual Rev 4.0, was not followed. Use of that operational procedure might have prevented the system overpressurization. A new local procedure for field use will be developed containing all operational steps, notes, cautions, and warnings.
15、The procedure will include a section requiring that such equipment undergo purge and functional checkout in a NASA lab before use in the field. All operators will be trained on the use of the new procedure and the IDC. 8. At the time of this close call, KSC did not have a process to certify prototyp
16、e equipment used on the Center. Recommendation(s): 1. Valves that do not perform a NASA-required valve function should be physically disabled. 2. Valves that do not perform a NASA-required valve function should not be incorporated into larger designs and should not be included in procurement specifi
17、cations. 3. KSC project teams should review procurement specifications for prototypes more closely to ensure that KSC requirements, including those for hazardproofing and electrical design, are part of the procurement specification. 4. Engineering Review Boards reviewing requests to use prototypes s
18、hould assign a single, dedicated point of contact to be responsible for verifying the prototypes compliance with design requirements (mechanical, electrical, pneumatic, reliability, etc.) for use at KSC and to request any warranted waivers. 5. A formal approved procedure should be in place for the o
19、peration of a prototype after design verification. 6. An approved user training course should be in place for prototype operation procedures after design verification. 7. All hardware, whether COTS or prototype, used in proximity of a space vehicle requires the performance of all design, operation,
20、and training verification procedures. Evidence of Recurrence Control Effectiveness: N/A Documents Related to Lesson: NASA Design Requirements NSTS 07700 Volume 10, Flight and Ground System Specification SW-E-0002, Ground Support Equipment General Design Requirements KSC-STD-E-0002E, Hazardproofing o
21、f Electrically Energized Equipment, Standard for KSC-E-165E, Electrical Ground Support Equipment Fabrication, Specification for KDP-P-2761, Engineering Directorate: Boards, Panels, and Reviews: Structure and Process Document KDP-P-1533, Prototype Development Laboratory Process Mission Directorate(s)
22、 Exploration Systems Additional Key Phrase(s): 1.Configuration Change Control 1.Ground support systems 1.Ground processing and manifesting 1.Launch Systems 1.Mishap Reporting 1.Program and Project Management Provided by IHSNot for ResaleNo reproduction or networking permitted without license from I
23、HS-,-,- 1.Research & Development 1.Reliability 1.Acquisition / procurement strategy and planning 1.Business processes 1.Cross Agency coordination 1.Configuration control and data management 1.DDT/E 1.Early requirements and standards definition 1.Engineering design and project processes and standards
24、 1.Ground Operations 1.Ground Equipment 1.Configuration Management 1.Review systems and boards 1.Launch Process 1.Review boards Additional Info: Project: Space Shuttle Program Approval Info: Approval Date: 2011-01-26 Approval Name: mbell Approval Organization: HQ Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
