Standard Article

Requirements for Certification of Composite Airframes: Historical Evolution

  1. John C. Halpin

Published Online: 20 JUL 2012

DOI: 10.1002/9781118097298.weoc022

Wiley Encyclopedia of Composites

Wiley Encyclopedia of Composites

How to Cite

Halpin, J. C. 2012. Requirements for Certification of Composite Airframes: Historical Evolution. Wiley Encyclopedia of Composites. 1–28.

Author Information

  1. JCH Consultants Inc., Centerville, OH

Publication History

  1. Published Online: 20 JUL 2012

Abstract

The process for certification of composite structures for civilian, CIVIL, and military, MIL, aircraft has been evolving for about 40 years. The technology base for the certification process is now mature enough to support the process. This article describes how the certification process has been tailored to the specific sensitivities of the polymeric matrix material component in the composite structures. Matrix sensitivities strongly influence the certification process: the material allowables, the need for environmental compensation load factors in the static test demonstration, the use of load enhancement factors and environmental conditions in the fatigue and damage tolerance testing, and material and process management for composite structures. The evolution of material and design values for composites is presented with suggestions for improving the cost and schedule efficiency for essential database supporting the airframe certification.

Keywords:

  • composite materials;
  • material and design allowables;
  • graphite/epoxy;
  • aircraft;
  • analysis;
  • environmental compensation load factors (ECLFs);
  • load enhancement factors (LEFs)