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The Salton Sea is a saline, endorheic rift lake located directly on the San Andreas Fault predominantly in California's Imperial Valley. The lake occupies the lowest elevations of the Salton Sink in the Colorado Desert of Imperial and Riverside Counties in Southern California. Like Death Valley, it is below sea level; currently, its surface is 226 ft (69 m) below sea level. The deepest area of the sea is 5 ft (1.5 m) higher than the lowest point of Death Valley. The sea is fed by the New, Whitewater, and Alamo rivers, as well as agricultural runoff drainage systems and creeks. The creation of the Salton Sea of today started in 1905, when heavy rainfall and snowmelt caused the Colorado River to swell, overrunning a set of headgates for the Alamo Canal. The resulting flood poured down the canal and breached an Imperial Valley dike, eroding two watercourses, the New River in the west, and the Alamo River in the east, each about 60 miles (97 km) long. Over a period of approximately two years these two newly created rivers sporadically carried the entire volume of the Colorado River into the Salton Sink. The Southern Pacific Railroad attempted to stop the flooding by dumping earth into the canal's headgates area, but the effort was not fast enough, and as the river eroded deeper and deeper into the dry desert sand of the Imperial Valley, a massive waterfall was created that started to cut rapidly upstream along the path of the Alamo Canal that now was occupied by the Colorado. This waterfall was initially 15 feet (4.6 m) high but grew to a height of 80 feet (24 m) before the flow through the breach was finally stopped. It was originally feared that the waterfall would recede upstream to the true main path of the Colorado, attaining a height of up to 100 to 300 feet (30 to 91 m), from where it would be practically impossible to fix the problem. As the basin filled, the town of Salton, a Southern Pacific Railroad siding and Torres-Martinez Indian land were submerged. The sudden influx of water and the lack of any drainage from the basin resulted in the formation of the Salton Sea. The continuing intermittent flooding of the Imperial Valley from the Colorado River led to the idea of the need for a dam on the Colorado River for flood control. Eventually, the federal government sponsored survey parties in 1922 that explored the Colorado River for a dam site, ultimately leading to the construction of Hoover Dam in Black Canyon, which was constructed beginning in 1929 and completed in 1935. The dam effectively put an end to the flooding episodes in the Imperial Valley. The lake's salinity, about 44 g/L, is greater than the waters of the Pacific Ocean (35 g/L), but less than that of the Great Salt Lake; the concentration is increasing by about 1 percent annually. [READ THE REST OF THIS ARTICLE]



On January 24, 1963 a USAF Boeing B-52C Stratofortress with nine crew members on board lost its vertical stabilizer due to buffeting stresses during turbulence at low altitude and crashed on Elephant Mountain in Piscataquis County, Maine, six miles from Greenville. The pilot and the navigator survived the accident. The crew's training mission was called a Terrain Avoidance Flight to practice techniques to penetrate Advanced Capability Radar (ACR) undetected by Soviet air defense during Cold War. ACR training flights had already been made over the West Coast of the United States on Poker Deck routes. This was to be the first low level navigation flight, utilizing terrain following radar, in the Eastern United States. One hour later, around 2:30 p.m. the Stratofortress crossed the Princeton VOR, descended to 500 feet (152 meters) and started its simulation of penetrating enemy airspace at low altitude with an airspeed of 280 knots. Approximately 22 minutes later, just after passing Brownville Junction in the center of Maine, the aircraft encountered turbulence. The pilot and crew commander, Westover's Most Senior Standardization Instructor Pilot, started to climb above it when the vertical stabilizer came off the plane with a "loud noise sounding like an explosion". Having suffered severe damage, the B-52C went into a 40 degree right turn, pointing its nose down. The pilot ordered to abandon the Boeing when he could not level it. The navigator who was operating as electronic warfare officer, ejected first. He was followed by the pilot and the copilot, there was neither enough altitude nor time for the seven lower-deck crew members to escape before the aircraft crashed into the west side of Elephant Mountain at 2:52 p.m. The copilot suffered fatal injuries striking a tree a mileaway from the main crash site. The pilot landed in a tree 30 feet above the ground. He survived the night, with temperatures reaching almost -30F below zero, in his survival kit sleeping bag atop his life raft. The navigator's parachute did not deploy upon ejection. He impacted the snow covered ground before separating from his ejection seat about 2,000 feet from the wreckage at a force estimated at 16 times the force of gravity. He suffered a fractured skull and three broken ribs. The force bent his ejection seat and he could not get his survival kit out. He survived the night by wrapping himself up in his parachute. The crash was caused by turbulence-induced structural failure. Due to buffeting stresses the stabilizer shaft broke and the B-52's vertical stabilizer came off the plane. It was found 1.5 miles from where the plane impacted the mountain side. With the loss of the vertical stabilizer, the aircraft had lost its directional stability and rolled uncontrollably. B-52C 53-0406, which crashed on Elephant Mountain, was the second high tailed B-52 to suffer such a fatal structural failure. After extensive testing, another two fatal crashes and one year later, Boeing found out that turbulence would over-stress the B-52's rudder connection bolts, causing first a rudder and subsequently a tail failure. The bolts were strengthened throughout the fleet which fixed the problem. [READ THE REST OF THIS ARTICLE]





The Bell AH-1 SuperCobra is a twin-engine attack helicopter based on the US Army's AH-1 Cobra. The twin Cobra family includes the AH-1J SeaCobra, the AH-1T Improved SeaCobra, and the AH-1W SuperCobra. The AH-1W is the backbone of the United States Marine Corps's attack helicopter fleet, but will be replaced in service by the AH-1Z Viper upgrade in the next decade. The AH-1 Cobra was developed in the mid-1960s as an interim gunship for the U.S. Army for use in Vietnam. The Cobra shared the proven transmission, rotor system, and the T53 turboshaft engine of the UH-1 "Huey". By June 1967, the first AH-1G HueyCobras had been delivered. Bell built 1,116 AH-1Gs for the U.S. Army between 1967 and 1973, and the Cobras chalked up over a million operational hours in Vietnam. The U.S. Marine Corps was very interested in the AH-1G Cobra, but preferred a twin-engined version for improved safety in over-water operations, and also wanted a more potent turret-mounted weapon. At first, the Department of Defense had balked at providing the Marines with a twin-engined version of the Cobra, in the belief that commonality with Army AH-1Gs outweighed the advantages of a different engine fit. However, the Marines won out and awarded Bell a contract for 49 twin-engined AH-1J SeaCobras in May 1968. As an interim measure, the U.S. Army passed on 38 AH-1Gs to the Marines in 1969. The AH-1J also received a more powerful gun turret. It featured a three barrel 20 mm XM197 cannon that was based on the six barrel M61 Vulcan cannon. Marine Cobras provided support for the US humanitarian intervention in Somalia, during Operation Restore Hope in 1992-1993. They were also employed during the US invasion of Haiti in 1994. USMC Cobras were used in US military interventions in the former Yugoslavia in the 1990s, and assisted in the rescue of USAF Captain Scott O'Grady, after his F-16 was shot down by a SAM in June 1995. AH-1 Cobras continue to operate with the U.S. Marine Corps. USMC Cobras were also used in operations throughout the 1990s. USMC Cobras have also served in Operation Enduring Freedom in Afghanistan and in Operation Iraqi Freedom in the ongoing conflict in Iraq. While new replacement aircraft were considered as an alternative to major upgrades of the AH-1 fleet, Marine Corps studies showed that an upgrade was the most affordable, most supportable and most effective solution for the Marine Corps light attack helicopter mission. [READ THE REST OF THIS ARTICLE]





The Minigun is a 7.62 mm, multi-barrel machine gun with a high rate of fire (up to 6,000 rounds per minute), employing Gatling-style rotating barrels with an external power source. In popular culture, the term "minigun" has come to refer to any externally-powered Gatling gun of rifle caliber, though the term is sometimes used to refer to guns of similar rates of fire and configuration, regardless of power source and caliber. Specifically, minigun refers to a single weapon, originally produced by General Electric. The "mini" of the name is in comparison to designs that use a similar firing mechanism but larger shells, such as General Electric's earlier 20 mm M61 Vulcan. The basic weapon is a 6-barrel, air-cooled, and electrically driven machine gun. The electric drive rotates the weapon within its housing, with a rotating firing pin assembly and rotary chamber. The minigun's multibarrel design helps prevent overheating, but also serves other functions. Multiple barrels allow for a greater capacity for a high firing rate, since the serial process of firing/extraction/loading is taking place in all barrels simultaneously. Thus, as one barrel fires, two others are in different stages of shell extraction and another three are being loaded. The minigun is composed of multiple closed-bolt rifle barrels arranged in a circular housing. The barrels are rotated by an external power source: usually electric, pneumatic, or hydraulic. Other rotating-barrel cannons are powered by the gas pressure or recoil energy of fired cartridges. A gas-operated variant, designated the XM133, was also developed, but was not put into production. Various iterations of the minigun have also been used in a number of armament subsystems for helicopters, with most of these subsystems being created by the United States. The first systems utilized the weapon in a forward firing role, for a variety of helicopters, some of the most prominent examples being the M21 armament subsystem for the UH-1 Iroquois and the M27 for the OH-6 Cayuse. It also formed the primary turret mounted armament for a number of members of the AH-1 Cobra family. The weapon was also used as a pintle-mounted door gun on a wide variety of transport helicopters, a role it continues to serve in today. [READ THE REST OF THIS ARTICLE]



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