Document Title: High-Energy Wide-Area Blunt Impact for Composite Structures
Summary: To show compliance with Title 14, Code of Federal Regulations (14 CFR) 25.571(a), the applicant must show, among other things, that catastrophic failure due to accidental damage will be avoided for the life of the airplane. The applicant is required to consider possible damage scenarios when evaluating accidental damage that could result in catastrophic failure. One of these damage scenarios the applicant should assess is accidental damage caused by high-energy wide-area blunt impact (HEWABI) events. HEWABI events (e.g. impacts by service vehicles) are impacts that are spread over a large area that may cause considerable structural damage. While the damage caused by a HEWABI event is typically readily visible in metallic structure, it may leave little or no external indications in composite structure. To ensure that any potentially catastrophic damage resulting from a HEWABI event is detected and repaired, applicants must provide appropriate conditional inspection instructions, or other procedures, to be implemented at the occurrence of such impact events as required per § 25.571(a)(3).
Documents for Download: Draft Document (MS Word)
Draft Document Comment Grid (MS Word)
Reference: 14 CFR 25.571, 25.1529, and appendix H to part 25
Comments Due: November 13, 2015
How to Comment: Email comments to:

Deliver comments by mail or hand to:
Federal Aviation Administration
Transport Airplane Directorate
Standards Staff, Standardization Branch, ANM-113
1601 Lind Avenue SW
Renton, WA 98057

Fax comments to: