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Aircraft EWIS regulations in China


There have been significant developments in the Chinese aerospace industry over the last couple of years. The largest of these developments is the design commencement of the Comac C919 narrow-body aircraft. It is a huge undertaking with the projected introduction into service in 2018.

It has been necessary to standup an infrastructure capable to support this massive aerospace project. The infrastructure considerations include a regulatory framework capable of certifying the new aircraft. For those organizations looking to work in the China market, it is necessary to understand the Civil Aviation Administration of China (CAAC) requirements and regulations in regards to EWIS.


The FAA’s EWIS regulations released in 2008 created new requirements governing EWIS system design, maintainability, modification, and certification. These regulations were the result of a decade-long effort that included thousands of man-hours of research, inspections, and analysis. All put together, the seventeen regulations made up the Part 25.1700 series.

EWIS Regulations

EWIS Compliance Checklist

Understanding the requirements and depth of testing, design, and analysis necessary to meet regulatory expectations is not something that can be achieved overnight. Those who are familiar with the FAA’s EWIS certification requirements will have an advantage in the Chinese aerospace industry. The following is a listing of the FAA’s EWIS requirements vis-à-vis the CAA of China.

FAA Regulation China Civil Aviation Authority
§25.1701 Definition Definition
§25.1703 Function and installation: EWIS. Function and installation: EWIS.
§25.1705 Systems and functions: EWIS. Systems and functions: EWIS.
§25.1707 System separation: EWIS. System separation: EWIS.
§25.1709 System safety: EWIS. System safety: EWIS.
§25.1711 Component identification: EWIS. Component identification: EWIS.
§25.1713 Fire protection: EWIS. Fire protection: EWIS.
§25.1715 Electrical bonding and protection against static electricity: EWIS. Electrical bonding and protection against static electricity: EWIS.
§25.1717 Circuit protective devices: EWIS. Circuit protective devices: EWIS.
§25.1719 Accessibility provisions: EWIS. Accessibility provisions: EWIS.
§25.1721 Protection of EWIS. Protection of EWIS.
§25.1723 Flammable fluid fire protection: EWIS. Flammable fluid fire protection: EWIS.
§25.1725 Powerplants: EWIS. Powerplants: EWIS.
§25.1727 Flammable fluid shutoff means: EWIS. Flammable fluid shutoff means: EWIS.
§25.1729 Instructions for Continued Airworthiness: EWIS. Instructions for Continued Airworthiness: EWIS.
§25.1731 Powerplant and APU fire detector system: EWIS. Powerplant and APU fire detector system: EWIS.
§25.1733 Fire detector systems, general: EWIS. Fire detector systems, general: EWIS.

One thing that is immediately apparent is that the regulation requirement sections seem to match up one-to-one. This certainly helps those that are creating certification packages for multiple organizations.

Between the Lines

But a regulation is more than just a heading. There could be differences between the wording and requirements of the CAA and the FAA. A comparative review of requirements between the two sets of regulations was performed by Lectromec. This review found no significant differences between the two sets of regulations. For example, the following shows the (Google) translated version of the CAA requirement 25.1709 and FAA 25.1709.

§25.1709 System Security: EWIS. Each EWIS must be designed and installed so that: (a) a catastrophic failure condition (A) is highly unlikely, and (2) is not caused by a single failure. (b) Each hazardous failure condition is extremely remote. §25.1709 System safety: EWIS. Each EWIS must be designed and installed so that: (a) Each catastrophic failure condition— (1) Is extremely improbable; and (2) Does not result from a single failure. (b) Each hazardous failure condition is extremely remote.

Technologies and evaluations that have been shown to meet FAA EWIS regulations will find common ground with the current CAA regulations. Tools and analyses developed with a focus on FAA regulatory requirements (such as Lectromec’s EWIS RAT and ADMT) can be easily integrated into existing processes for those looking to show compliance with the EWIS regulations of the CAAC.

Michael Traskos

Michael Traskos

President, Lectromec

Michael has been involved in wire degradation and failure assessments for more than a decade. He has worked on dozens of projects assessing the reliability and qualification of EWIS components. In September 2014, Michael was appointed as an FAA DER with a delegated authority covering EWIS certification.