An FAA notice of proposed rulemaking (NPRM) would revise Part 25 standards to allow the failure of certain non-structural partitions. The FAA says this action is necessary because, in some cases, “it is not practical to design partitions in certain airplane compartments to withstand a large decompression event that occurs within that compartment.” Although individual partition failure would be allowed, “continued safe flight and landing would still be required.”
Currently, Part 25 requires bulkheads, floors, partitions, and partition doors to withstand sudden decompression. But for certain smaller compartments, such as lavatories, private suites, and crew rest areas, the agency conceded it may be difficult to achieve compliance because a large decompression hole would result in very high air loads on the partitions. “Strengthening the partitions to sustain such high loads has been shown to be impractical in many cases for these smaller compartments because it could adversely affect the structural integrity of the aircraft.”
Another reason for relaxing the rule is the FAA’s admission of its inconsistent use of certifying numerous airplanes to the current standards based on a finding of an equivalent level of safety (ELOS), the first of which was made in 1989. “The agency…has not consistently applied the ELOS rule and applicants have raised questions about the intent of the rule during recent certification programs.”
The revised standards would apply to new type certificates (TCs) and cabin interior design modifications under TCs or STCs. Comments on the NPRM are due June 15.
