Abstract: The U.S. Coast Guard (USCG) uses HC-130 aircraft for search and rescue (SAR) and other missions. The aircraft are presently equipped with two to four 20 person inflatable life rafts, stowed in cells in the wings. Similar rafts are also used for SAR missions, dropped to survivors from low altitude. The existing HC-130 wing life rafts are reversible, and rely primarily on a drogue both to reduce drift rates and provide some increased resistance to lifting out or capsizing. By contrast, several current designs of rafts, many of which are already in service as survival rafts for commercial ships and smaller craft, incorporate fabric ballast bags, attached below the buoyancy tubes. These bags are intended to rapidly flood with seawater once the raft is afloat. A prototype raft intended to serve as a replacement for the existing raft incorporates a ballast system of this type. This report summarizes a general review of the available literature on life raft behavior in extreme wind and sea conditions. It emphasizes the underlying physical mechanisms of life raft capsizing, life raft resistance to capsize, raft drift forces and speeds, potential hazards to life raft occupants as a result of extreme motions and sea loads, including capsize in breaking waves, effects of extreme sea loads and unusual attitudes on life raft integrity, and stability criteria and related test requirements currently in effect. The report also summarizes observations made during acceptance tests (inflation, righting, and canopy erection tests) of the prototype HC-130 replacement raft, observations and measurements taken during sea-tests for comparison of existing and prototype rafts, and lift-out force tests in accordance with USCG proposed rules.
| Limitations: |
 APPROVED FOR PUBLIC RELEASE |
| Description: |
Final rept. Dec 95-Jul 97 |
| Pages: |
102 |
| Report Date: |
NOV 1997 |
| Report Number: |
A462733 |
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