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The 1958 Tybee Island B-47 crash was an incident on February 5, 1958 in which the United States Air Force lost a 7,600 pound (3,500 kg) Mark 15 hydrogen bomb in the waters off Tybee Island near Savannah, Georgia, USA. The bomb was jettisoned to save the aircrew during a practice exercise after the B-47 bomber carrying it collided in midair with an F-86 fighter plane. Following several unsuccessful searches, it was presumed lost somewhere in Wassaw Sound off the shores of Tybee Island. GeorgiaThe B-47 bomber was on a simulated combat mission from Homestead Air Force Base in Florida. It was carrying a single 7,600-pound (3,400 kg) bomb. At about 2:00 AM, the B-47 collided with an F-86. The F-86 crashed after the pilot ejected from the plane, but the B-47, despite being damaged, remained barely airworthy enough to fly. The crew requested permission to jettison the bomb in order to reduce weight and prevent the bomb exploding during an emergency landing. Permission was granted and the bomb was jettisoned at 7,200 feet (2,200 m) while traveling about 200 knots (370 km/h). The crew did not see an explosion when the bomb impacted the sea. They managed to land the B-47 safely at Hunter Army Air Field. The pilot, Colonel Howard Richardson, was awarded the Distinguished Flying Cross after this incident for his role in piloting the B-47. Starting on February 6, 1958, the Air Force 2700th Explosive Ordnance Disposal Squadron and 100 Navy personnel equipped with hand held sonar and galvanic drag and cable sweeps mounted a search. On April 16, 1958 the military announced that the search efforts had been unsuccessful. Based upon a hydrologic survey, the bomb was thought[who?] to lie buried under 5 to 15 feet (2 to 5 m) of silt at the bottom of Wassaw Sound. In 2004, retired Air Force Colonel Derek Duke incorrectly claimed to have found the possible resting spot of the bomb. He and his partner located the spot by trawling the area in their boat with a Geiger counter in tow. The Air Force released its report in June 2005, which stated that high radiation measurements are from naturally occurring radioactive materials, and that the location of the bomb is still unknown. [READ THE REST OF THIS ARTICLE]



Friction welding (FW) is a class of solid-state welding processes that generates heat through mechanical friction between a moving workpiece and a stationary component, with the addition of a lateral force called "upset" to plastically displace and fuse the materials. Technically, because no melt occurs, friction welding is not actually a welding process in the traditional sense, but a forging technique. However, due to the similarities between these techniques and traditional welding, the term has become common. Friction welding is used with metals and thermoplastics in a wide variety of aviation and automotive applications. The combination of fast joining times (on the order of a few seconds), and direct heat input at the weld interface, yields relatively small heat-affected zones. Friction welding techniques are generally melt-free, which avoids grain growth in engineered materials, such as high-strength heat-treated steels. Another advantage is that the motion tends to "clean" the surface between the materials being welded, which means they can be joined with less preparation. During the welding process, depending on the method being used, small pieces of the plastic metal will be forced out of the working mass (flash). It is believed that the flash carries away debris and dirt. Another advantage of friction welding is that it allows dissimilar materials to be joined. This is particularly useful in aerospace, where it is used to join lightweight aluminum stock to high-strength steels. Normally the wide difference in melting points of the two materials would make it impossible to weld using traditional techniques, and would require some sort of mechanical connection. Friction welding provides a "full strength" bond with no additional weight. Spin welding systems consist of two chucks for holding the materials to be welded, one of which is fixed and the other rotating. Before welding one of the work pieces is attached to the rotating chuck along with a flywheel of a given weight. The piece is then spun up to a high rate of rotation to store the required energy in the flywheel. Once spinning at the proper speed, the motor is removed and the pieces forced together under pressure. The force is kept on the pieces after the spinning stops to allow the weld to "set". This technique is also known as inertia welding, rotational welding or inertial friction welding. [READ THE REST OF THIS ARTICLE]





The Florida stone crab, Menippe mercenaria, ranges from North Carolina to Panama. It is brownish red with gray spots and a whitish underside. It has large and unequally-sized claws with black tips. In addition to the usual sexual dimorphism exhibited by crabs, female stone crabs have smaller but deeper carapaces than males of a similar age, and males generally have larger chelae than females. Males grow faster than females, and the proportional size of males claws always increases. Female claw size increases relative to body size only through the small-juvenile stage; in the large-juvenile and adult stages, the body and claws grow at proportionally the same rate. The stone crab fishery is unique because only the claws are harvested; the crab is released back into the water and can grow new claws if it survives the declawing process. Legal-sized claws must be 2.75 inches long, measured from the tips of the immovable finger to the first joint. Florida stone crabs are legal for harvest from October 15 until May 15. Prepared Florida stone crab claws. In Florida, all stone crabs are usually fished in open water from nearshore to 6080 ft depth, using traps that have specific legal requirements. The bodies of harvested crabs are not taken because there is very little meat in the body. The claws, which are large and strong, are considered a delicacy. Harvesting is accomplished by removing one or both claws from the live animal and returning the crab to the ocean where it can regrow the lost limb(s) in 12-14 months. Because stone crabs usually die if their claws are not removed properly, it is important to remove the claws correctly when harvesting them. If both claws are legal-sized, they may both be taken. The probability of surviving the declawing process and living to grow new claws is doubled if only one claw is taken. Stone crabs are carnivores and do not eat seagrass or algae. When a stone crab loses both claws, its diet changes from large mollusks to very small mollusks and other invertebrates. It has hard, sharp, pointed tips on its legs and uses those to probe into sediment and dig or pick out small mollusks. It also will forage on small invertebrates (worms, mollusks) on seagrass blades. It has multiple sharp mouth parts that can penetrate the shells of small prey items. Stone crabs have been popular, specialty food items for 50 years. Per pound of meat, they are the most expensive seafood item sold in the USA. [READ THE REST OF THIS ARTICLE]



The Christmas Island red crab, Gecarcoidea natalis, is a species of terrestrial crab endemic to Christmas Island in the Indian Ocean. Although restricted to a relatively small area, it is estimated that up to 120 million red crabs may live there, making it the most abundant of the 14 terrestrial crab species on Christmas Island. Christmas Island red crabs eat mostly fallen leaves and flowers, but will occasionally eat other animals, including other red crabs if the opportunity arises. The carapace is up to 116 millimetres (4.6 in) long, rounded, and encloses the gills. The claws are usually of equal size, unless one becomes injured or detached, in which case the limb will regenerate. During that time, it will be the smaller of the two. The male crabs are generally larger than the females, while adult females have a much broader abdomen and usually have smaller claws. The broader abdomen of the female Christmas Island red crab only becomes apparent in the third year of growth. Christmas red crabs live in burrows, in order to shelter from the sun. Since they still breathe through gills, the possibility of drying out is a great danger for them. They are famous for their annual migration to the sea in order to lay their eggs in the ocean. During the migration, the crabs cover the highway routes to the coast so densely that they can be seen from the air. Volunteers shovel the crabs off the roads and, although no harm is intended, some of the countless millions of crabs inevitably get injured. Early inhabitants of Christmas Island hardly ever mentioned these crabs. It is possible that their famous large population size was caused by the extinction of the endemic Maclear's Rat, Rattus macleari in 1903, which may have kept the crab's population in control. An exploding population of the yellow crazy ant, an invasive species accidentally introduced to Christmas Island and Australia from Africa, is believed to have killed 1520 million red crabs in recent years. [READ THE REST OF THIS ARTICLE]





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