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West Marine/Sea Star Life Raft Test Life
Raft Study provided by West Marine,
for additional information dial (800)BOATING Sponsored by: INDEX The Tinker Traveller is a combination inflatable dinghy and survival craft. In appearance, it is similar to an inflatable dinghy like those made by Avon, Zodiac, and West Marine. It has a segmented plywood floor, hard transom, and small dodger on the bow. It incorporates an inflatable survival canopy which encloses the occupants to reduce exposure. In addition, it is supplied with a compact sloop sailing rig with a daggerboard and rudder. This rig, plus conventional oars, allow the Tinker to be sailed or rowed reasonably well so that its crew might be able to reach land or travel to shipping lanes where the chance of rescue is greater. This test was conducted in the open ocean, in an area NW of the Golden Gate of San Francisco Bay known as the Potato Patch Shoal. This area is north of the main ship channel into San Francisco Bay which is on an approximate course of 60°/240° magnetic. While the ship channel is dredged to about 10 fathoms, the shoals to the north and south of this channel are very rough due to the shallow depths of around 4 fathoms. Waves frequently break during storm conditions, especially during an ebb tide. Due to the strong currents and constricted entrance at the Golden Gate, short wavelength and steep sided chop is abundant, along with the longer Pacific swells. The characteristic "beaten egg white" chop of the Golden Gate provided a remarkably tippy surface to test the capsize resistance of the tested craft. Typical summer conditions for this area prevailed during this test. Winds at the 1000 PDT launch time were from the NW at 20 knots (force 5). Over the course of the day, winds increased to a steady 25 knots with frequent gusts above 30 knots (force 6-7). Waves were about four feet at the start (sea state 3), building to 6-8 feet (sea state 4-5) at 1400. Whitecaps were present all day long. The primary support vessel was a Garden 51 fiberglass ketch, Sea Star. In addition, a Tinker 10' dinghy was used to ferry participants between the life rafts and Sea Star. Ray Thackeray provided his vessel Sea Star, the Tinkers, and three crew members who helped to document the event on video and slide film. West Marine provided six associates, most of whom had extensive offshore sailing experience. Due to the rough conditions, it was not possible to exchange crews as we had done in past tests. Ray Thackeray and Chuck Hawley were the primary testers, with Scott Lonsway and Pepe Parsons also spending time in the MD-2 raft. Conditions were perfect for inducing motion sickness, and several crew members on the large support vessel were affected by it. Both of our liferaft testers became sufficiently nauseated to vomit. This was associated with specific functions on board the rafts: orally inflating the MD-2 floor, victim recovery from the water where water was ingested, and projects requiring concentration inside the canopies. Normal methods for reducing motion sickness were effective, particularly getting outside the enclosures so that the visual equilibrium was established. A Navico Axis handheld VHF radio was used for communications between the rafts and the support vessel . This worked well until it was immersed. We believe that the presence of water in the microphone area made the transmission excessively garbled, although the battery may have run down at that point. A Standard Communications HX-230S was also used in a protective vinyl bag, and it performed well. Since it has a relatively large PTT button, the HX-230S was quite easy to operate. Below is a brief description of the craft tested: Switlik MD-2 The Switlik MD-2 is a 6 person raft, meeting the ORC regulations for offshore sailing races. It has two buoyancy tubes with a large self-supported canopy. It is constructed of heat welded polyurethane fabric and is octagonal in shape. It was supplied with Switlik's optional inflatable floor. It was packed in the Switlik Cordura nylon valise. The MD-2 is the newest of Switlik's yachting life rafts, and it borrows many design features from their other models. Some of these features are as follows:
Tinker Traveller The Tinker Traveller is a dual purpose dinghy and life boat. Without its sailing rig and canopy, it resembles a conventional 12' inflatable sportboat. With its sailing rig in place, the Traveller can be sailed reasonably well upwind and down. With the inflatable canopy in place, the Traveller resembles a small covered wagon, with enough space for two or three adults and some provisions. It can also be fitted with manually operable CO2 inflation cylinders for rapid inflation of the hull chambers. The hull fabric is a Hypalon/neoprene mixture, while other components appear to be heat welded polyurethane/nylon fabric. The Traveller is a six person dinghy, although is does not have enough room for six as a life boat. The Traveller features "hull within a hull" construction. Inflatable inner portions of the main tubes provide reserve buoyancy should the outer tubes become punctured. This capability was not tested. The Tinker Lifeboat was designed after the Fastnet Race of 1979 in which hundreds of boats were subjected to gale conditions, and 15 yachtsmen lost their lives. The requirements were as follows:
COMPARISON OF EQUIPMENT/CONSTRUCTION/SPECIFICATIONS
The bow dodger of the Traveller covers an area approximately 2 feet in length, which could be used for storage or leg room. It is a wedge-shaped area which tapers towards the bow. |