Plastics for Aircraft Interior Applications

FAR 25.853 Tested and Flame Resistant

Plastic materials are a good solution to reduce fuel consumption thanks to their low weight in comparison to metals. To be considered for an Aircraft Interior application, interior materials must fulfill several technical requirements designed to limit the consequences of fire in the cabin and maintain reasonable safety levels for the passengers. To ensure fire protection in aircraft, the Federal Aviation Administration (FAA) requires various fire testing procedures (such as FAR 25.853) to demonstrate that aircraft materials meet specific performance criteria when exposed to heat or flames.

We are industry unique.

When we consider the standard range of plastic stock shapes, high performance materials such as PEEK, PEI, PPS typically meet requirements for flame resistance without modification; on the other hand, standard materials such as PA usually do not unless they have been modified with special additives.
This is the reason why we distribute several new thermoplastic products, with a flame-retardant additive: these materials are designed to meet the typical demands of aircraft interiors and can be a lower cost alternative to high performance materials when high mechanical performance or temperature resistance is not required.
These new aircraft interior plastics manufactured by Ensinger Plastics are tested according to FAR 25.853 are:

  • PA 6 FRT – TECAMID 6 FRT natural
  • PA 66 GF15 FR – TECAMID 66 GF15 FR black
  • PPE FR – TECANYL VH2 black / TECANYL VH2 grey

New Technology Plastics semi-finished plastic products as rods, sheets, and pipes / tubes, and keep a large stock portfolio. Custom production runs are also possible.

Ensinger has tested several high-performance thermoplastics as well for flammability:

  • PEEK natural – TECAPEEK natural
  • PEEK GF30 – TECAPEEK GF30 natural
  • PEEK CF30 – TECAPEEK CF30 black
  • PEEK PVX – TECAPEEK PVX black
  • PPS natural – TECATRON natural
  • PPS GF40 – TECATRON GF40 black
  • PPS PVX – TECATRON PVX black
  • PEI natural – TECAPEI natural
  • PEI GF30 – TECAPEI GF30 natural

Tested to either a 60 second vertical burn test standard or a 12 second vertical burn test standard, additional smoke emission and toxicity, and heat release tests can also be done if required.
New Technology Plastics offers a wide range of materials to cover the requirements for many applications in aircraft interior applications such as seats, lighting, galleys, or cockpit equipment. Given our ability to share these extensive test results with our customers, these “ready for use” materials truly open up new possibilities and opportunities for design improvements in commercial aircraft interiors and VIP aircraft interiors alike.
Aircraft interior materials designated for use in an aircraft cabin environment must meet certain flammability requirements.

However, it is the actual position of the part in the plane that will determine whether just the flammability test or the whole FST (Fire, smoke, and toxicity) test (detailed below) is required:

  • Flammability test as per 60 second and/or 12 second vertical burn test
  • Smoke density test / smoke emission
  • Combustion toxicity
  • Heat release
  • Flammability as per 15 second horizontal burn test

Ensinger’s, flammability test for plastics always indicates the thickness tested, and will correspond to the thinnest wall thickness admissible on the finished machined part from our semi-finished plastics. Please refer to material data sheets to check which test was passed for a given material. Flammability test certificates are available upon request at time of order.
The test results provided on our plastic materials are a great supplement customer can use to give an indication of potential results when performing final FST tests on machined parts or their subassemblies. It definitely allows them to select quickly, and with confidence the right material for a given application. We remain available for additional questions and can perform additional tests if necessary: for example, we may test additional thickness for flammability if required.

The requirements for use of materials in aircraft, and especially in aircraft interiors are quite similar all over the world and are clearly described by various regulatory agencies. A summary of related agency descriptions follows.

Aircraft regulation is mainly defined by 2 standards which are equivalent:

  • in USA : the FAR (Federal Aviation Regulation) which is part of the Title 14 of the CFR (Code of Federal Regulations), issued by the FAA (Federal Aviation Administration)
  • in EU : the CS (Certification Specifications) or the JAR (equivalent to FAR created in Europe), issued by EASA (European Aviation Safety Agency)

Large commercial aircraft are covered by section/part “25” for both standards; Aircraft Interiors are covered by section “853”. We therefore refer to “FAR 25.853”, JAR 25.853”, “JAR-25, § 25.853”, “FAR Part 25, § 25.853”,  “14 CFR Part 25.853”, “CS 25.853”

In order to define more detailed instructions and safety precautions, individual aircraft manufacturers have prepared their own internal documentation, all have similar content regarding FST requirements.

  • BSS : « BOEING SAFETY STANDARD » 
  • AITM : « AIRBUS INDUSTRIE TEST METHOD »; these AITM are gathered in the document « AIRBUS DIRECTIVE» ABD0031

 The different tests are described in the Appendix F of FAR/CS 25.

All the materials have to pass the vertical burn test. Some aircraft interior components such as interior ceiling, wall panels, partitions, galley structure, large cabinets or cabin stowage compartments must pass as well smoke emission and toxicity tests, as well as a heat release test.

Test descriptionFAR 25.853Airbus ABD 0031 specificationBoeint specification
Flammability 60 seconds VerticalFAR Part 25, § 25.853 (a) and Appendix F, Part I, para. (a)(1)(i)AITM 2.0002ABSS 7230 F1
Flammability 12 seconds VerticalFAR Part 25, § 25.853 (a) and Appendix F, Part I, para. (a)(1)(ii)AITM 2.0002BBSS 7230 F2
Flammability 15 seconds HorizontalFAR Part 25, § 25.853 (a) and Appendix F, Part I, para. (a)(1) (iv)AITM 2.0003BSS 7230 F3
FAR Part 25, § 25.853 (a) and Appendix F, Part I, para. (a)(1) (v)BSS 7230 F4
Heat ReleaseFAR Part 25, § 25.853 (d) and Appendix F, Part IVAITM 2.0006BSS 7322
Smoke DensityFAR Part 25, § 25.853 (d) and Appendix F, Part VAITM 2.0007A & BBSS 7238
Combustion ToxicityN/AAITM 3.0005BSS 7239