Composite Repair Engineering Case Studies for U.S. Army Aerostructures
Abstract
The U.S. Army fields a multitude of aircraft mission design series (MDS) developed by several different original equipment manufacturers with varying mission requirements and flight profiles. The H-64 Apache, H-60 Blackhawk, and H-47 Chinook are the U.S. Army's primary rotary-wing workhorses in the enduring fleet. These aircraft primarily have airframes composed of high strength aluminum alloys due to a provenance beginning within the second half of the 20th century. Advanced composite materials include portions of these aerostructure designs but mainly comprise secondary structures such as covers, fairings, spoilers, and antenna. More structurally critical applications include rotor blades, bulkheads, stringers, and stabilators. This paper will present examples of U.S. Army damaged composite aerostructures and will document an analysis approach for battle damage repairs using both scarf patch and scab patch methods. As this evaluation is presented, Classical Laminated Plate Theory (CLPT), finite element analysis (FEA), and bonded joint analysis will be applied to a representative U.S. Army battle damaged and worn component to substantiate structural repairs. This work will focus on a static analysis of composite structure repairs utilizing maximum allowable strain, stiffness, and bonded joint analysis through an equivalent strength methodology. The structural analysis in this work assumes the materials, tooling, skillsets, and capabilities are organically available and proper at the repair location.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 22, 2023
- Accession Number
- AD1208761
Entities
People
- Brian A. Cerovsky
- Bryan M. Steiner
- Jared R. Peltier
- Stephen J. Janny