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WSHWG Development of § 25.1705

WSHWG Development of § 25.1705. WSHWG Meeting No. 9 Bombardier Aerospace Montreal, Quebec. Stephen Slotte Task 6.6 Leader 10/6/02. Arc Tracking Video. Video by Lectromec Design Company. Boring Acronyms I Use. ARAC : Aviation Rulemaking Advisory Committee

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WSHWG Development of § 25.1705

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  1. WSHWG Development of § 25.1705 WSHWG Meeting No. 9 Bombardier Aerospace Montreal, Quebec Stephen Slotte Task 6.6 Leader 10/6/02

  2. Arc Tracking Video Video by Lectromec Design Company

  3. Boring Acronyms I Use • ARAC: Aviation Rulemaking Advisory Committee • ESHWG: Electrical Systems Harmonization Working Group • ATSRAC: Aging Transport Systems Rulemaking Advisory Committee • WSHWG: Wire Systems Harmonization Working Group • EWIS: Electrical Wiring Interconnection System 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  4. FAA JAA CAA, UK DGAC, France RLD, Netherlands Transport Canada AECMA ALPA Airbus Boeing Bombardier British Airways Cessna Dassault Aviation Embraer Thales Avionics Tyco Electronics WSWHG & ESWHG Members 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  5. What We Did Revised / New/Harmonized One Two Three DevelopStrategies forMitigating Effectsof Age CombineWire RelatedFARs/JARs DevelopWire Safety AssessmentRequirements • Harmonized Electrical System Requirements • New/Revised EWIS Requirements • Advisory Material for EWIS Requirements Six Four Five Develop WireSeparationRequirements Develop WireIdentificationRequirements DevelopAdvisoryMaterial 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  6. WSHWG Existing, Proposed, & Final FAR/JAR Part 25 Revisions New FAR/JAR 25 Existing FAR/JAR 25 A §25.611 § 25.1310 § 25.773 § 25.1316 §25.855 § 25.1331 § 25.863 §25.1351 §25.869 §25.1353 §25.899 §25.1355 § 25.903 §25.1357 §25.1165 §25.1360 § 25.1189 §25.1362 § 25.1203 §25.1365 § 25.1301 §25.1431 §25.1309 § 25.1529 A B Proposed Changes B C D C D E D E F E F G F G H G H 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  7. Some of the Big Hitters • EWIS: • Definition • System Function and Installation • System Safety • System Separation • System Component Identification • System Power Removal 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  8. STC Design & Installation Seat Track Wiring for IFE In-Service Condition

  9. EWIS As A “System” • EWIS is more than just wire • Multiple components • Wire • Connectors • Support devices • Etc…. • The multiple components make a whole • Shifting the paradigm about what a system is will raise awareness about the importance that wires and their components have toward producing a safe product

  10. EWIS As A “System” Aircraft wiring can no longer be thought of as a collection of single wires. It must be considered as integrated whose failures have an airplane level effect. 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  11. § 25.1701* EWIS Definition * Proposed to the FAA by the Aging Transport Systems Rulemaking Advisory Committee (Reference ATSRAC Task 6 Final Report to ATSRAC, Document No. WS-50-04)

  12. What is an EWIS? An electrical wiring interconnection system is defined as an electrical connection between two or more points including the associated termination devices and the necessary means for its installation and identification. 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  13. Wires & cables Connections to electrical devices CBs or other circuit protection devices Connectors & accessories Electrical grounding and bonding devices Electrical splices Conduits that have electrical termination for the purpose of bonding Clamps & other devices used to route and support the wire bundle Cable tie devices Labels or other means of identification Pressure seals associated with EWIS An EWIS Includes: 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  14. EWIS components inside shelves, panels, rack, junction boxes, distribution panels, back-planes of equipment racks including circuit board back-planes, wire integration units, etc An EWIS Also Includes: 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  15. Wiring inside avionics equipment Equipment including non-required miscellaneous equipment qualified to environmental conditions and testing procedures approved by the Administrator other than those specifically included in the definition Equipment qualified to a technical standard order Portable, carry-on, or otherwise non-permanently mounted electrical equipment Fiber optics Mating connection at the termination point of the wire on those devices that are excluded from the EWIS definition An EWIS Doesn’t Include:

  16. Electrical Wiring Interconnection System

  17. § 25.1703* EWIS Function & Installation * Proposed to the FAA by the Aging Transport Systems Rulemaking Advisory Committee (Reference ATSRAC Task 6 Final Report to ATSRAC, Document No. WS-50-04)

  18. Arc Tracking Video Video by Lectromec Design Company

  19. § 25.1703 - EWIS System Function & Installation • Similar to § 25.1301 but is broader • Examples: • Minimize • Mechanical strain • Damage by personnel movement • Damage by items carried onto the aircraft by passengers, cabin crew, and flightcrew • Hazardous effects of moisture must be minimized 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  20. EWIS System Function & Installation • EWIS modifications to the original type design must be designed and installed to the same standards used by the original aircraft manufacturer or other equivalent standards acceptable to the Administrator 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  21. Design & Installation NTSB Photographs

  22. § 25.1705* EWIS System Safety * Proposed to the FAA by the Aging Transport Systems Rulemaking Advisory Committee (Reference ATSRAC Task 6 Final Report to ATSRAC, Document No. WS-50-04)

  23. Federal Register Tasking Federal Register/Vol. 66, No. 103, Page 29203, Tuesday, May 29, 2001 • Identify requirements to conduct wire system safety assessments. • Review § 25.1309-1A (or latest revision), corresponding JAR-25 material, and related ARAC recommendations and recommend, if appropriate, particular methods of compliance with § 25.1309 that should be mandated in a new wire system rule. 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  24. § 25.1705: The Rule Objective Focus attention on EWIS and the safety issues associated with them using the concepts of § 25.1309 and provide a tool to find potential failures early in the design process 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  25. Failure Conditions • § 25.1705 failure conditions • Hazardous • Catastrophic • Same words as § 25.1309 • Same meaning as § 25.1309 • Hazardous must be shown to be extremely remote • Catastrophic must be shown to be extremely improbable 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  26. Too Many Splices!

  27. So What is § 25.1705 All About? • It’s like § 25.1309, but it’s NOT § 25.1309 • The proposed rule language is consistent with § 25.1309 • Requires EWIS to be analyzed for failure conditions that affect airplane level safety 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  28. Why This Rule? • History dictates the need: • Wire related incidents and accidents • Post-TC modifications have proven to be an issue time-and-time again • OEM delivered airplanes have had wiring issues out-the-door or they have developed in-service • Existing safety assessment requirements have not always been applied to wire systems • Inadequate application • Inconsistent application • Existing requirement does not go far enough • Current compliance activity is not sufficient

  29. Why This Rule? Current § 25.1309 SSA’s typically have not considered “cause” of a wire failure effecting other wires in the EWIS. They look at rotor burst, lightning, hydraulic line rupture, etc. But what about the failure of the EWIS created by a single wire chafing or arcing event taking out other functions supported by the EWIS?

  30. § 25.1705Pre & Post TC Safety Analysis Concept • Applies to applicants for pre-TC work and for amended TC’s and STC’s when the applicant is in possession of all pre-modification data for the areas the modification will effect • This means you have to be able to identify the systems in the EWIS under consideration for modification and the system functions associated with that EWIS 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  31. § 25.1705Post - TC Safety Analysis Concept • Applies to applicants for post-TC modifications where the applicant cannot identify the systems or systems function contained in EWIS under consideration for modification • Airplane manufacturers • Designated Alteration Stations • Other STC or ATC applicants • If you don’t know what’s in the bundle then stay away from it in a manner decided between you and the certifying authority

  32. Separation the Thickness of A Credit Card As Delivered Design and Installation

  33. § 25.1709* EWIS System Separation * Proposed to the FAA by the Aging Transport Systems Rulemaking Advisory Committee (Reference ATSRAC Task 6 Final Report to ATSRAC, Document No. WS-50-04)

  34. New & Expanded Separation Requirements for EWIS • Replaces the wiring separation requirements of § 25.1353 • Adds additional EWIS separation requirements, for example: 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  35. New & Expanded Separation Requirements for EWIS • Adds additional EWIS separation requirements, for example: • Fuel system components • Hydraulic system components • Oxygen system components • Waster/waste system components • Flight or other mechanical control system cables and associated components • Heated equipment, hot air ducts, and lines • Redundant systems • Aircraft structure, sharp edges, and corners 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  36. STC Design & Installation

  37. New & Expanded Separation Requirements for EWIS • Separation must be achieved by separation distance or barrier. In some cases other means shown to be at least equivalent is allowed. • NO specific separation distances or equivalent barrier are specified – the applicant must establish them based upon analysis of design and installation of specific features

  38. New & Expanded Separation Requirements for EWIS • Defining an adequate separation distance or equivalent barrier must include: • Electrical characteristics, amount of power and failure condition severity • Installation design features • Maximum amount of wire slack • Probable variations in the EWIS installation • Intended operating environment • Maintenance practices defined in the airplane manufacturers standard wiring practices manual. • Maximum temperature generated by adjacent wire/wire bundles during normal and fault conditions

  39. STC Design & Installation

  40. § 25.1711* EWIS Component Identification * Proposed to the FAA by the Aging Transport Systems Rulemaking Advisory Committee (Reference ATSRAC Task 6 Final Report to ATSRAC, Document No. WS-50-04)

  41. EWIS Component Identification § 25.1711 will require EWIS components to be labeled or otherwise identified to facilitate its identification, function, operating limitations, or any applicable combination of these factors. 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  42. EWIS Component Identification § 25.1711 imposes additional requirements for EWIS components that are required for safe flight, landing, egress, or have the potential to impact the ability of the flightcrew to cope with adverse operating conditions 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  43. EWIS Component Identification Post-TC modifications must be identified to the same standards used by the original aircraft manufacturer of other equivalent standards acceptable to the Administrator 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  44. EWIS Component Identification • EWIS component identification will help ensure that systems remain safe and operate as intended throughout the service life of the airplane. • Clear labeling will allow installers, inspectors, and maintainers to readily identify that the correct system components are installed as designed, and allows modifiers to add systems with due regard to the existing protection and separation requirements established by the original airplane manufacturer 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  45. Design & Installation

  46. § 25.1720* System Power Removal * Proposed to the FAA by the Aging Transport Systems Rulemaking Advisory Committee (Reference ATSRAC Task 6 Final Report to ATSRAC, Document No. WS-50-04)

  47. § 25.1720 Requires a Switch For airplane systems that require the ability to remove or reset power during normal operations the system must be designed such that circuit breakers are not the primary means to remove or reset system power 2nd Annual FAA EAPAS Conference Washington DC November 5-7, 2002

  48. Arc Tracking Video Video by Lectromec Design Company

  49. Questions? Comments? Complaints? Compliments? Just get off the stage?

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