Verification Testing of a UH-1 Wire Strike Protection System (WSPS)
Abstract
In-flight wire strikes poses a serious threat to low-level helicopter operations. Under the sponsorship of Headquarters, US Army Aviation Research and Development Command (AVARADCOM) tests were conducted by ATL to determine the suitability for UH-1H helicopter application of a Wire Strike Protection System (WSPS) manufactured by Bristol Aerospace Limited (BAL). The WSPS initially tested consisted of fuselage-mounted upper and lower cutters and a windshield centerpost deflector with a sawtooth cutter. Using the NASA-Langley Research Center's Impact Dynamics Research Facility, a UH-1H helicopter fitted with the WSPS was subjected to pendulum swing tests in which the helicopter struck strung wires at approximately 40 knots airspeed. The WSPS demonstrated its capability to sever an 11,500-pound tensile strength steel, seven-strand 3/8 guy wire. Also, a significant wire-cutting limitation peculiar to the UH-1H was identified. At wire impact 30 degrees from the normal to the flight path, it was demonstrated that the wire could be snagged by the windshield wiper shaft, preventing the wire from being deflected into the upper cutter. As a result, BAL and ATL analyzed the situation and both concluded that a simple windshield wiper shaft deflector could alleviate the problem. Windshield wiper shaft deflectors fabricated by BAL were installed on the test aircraft and additional swing tests were conducted. Successful deflection and wire cutting were demonstrated. Installation of the WSSPS,. as modified by this effort, on the Army's UH-1H helicopter fleet is recommended.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1982
- Accession Number
- ADA122220
Entities
People
- Leroy T. Burrows