Mil-tech bard
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Joined: Tue May 28, 2013 2:25 pm
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Getting back to the idea that Sharonan logistics are going to have huge disadvantages compared to Arcanian airlift. It ain't necessarily so. I have traveled through the railway pass in New Mexico that the Traisum (sp?) Cut is modeled on, and I have researched something called "Slack-line cableway excavators" which were available during it's construction. "Slack-line cableway excavators" were used extensively by the US Army Corps of Engineers in the major water projects that tamed the Mississippi. "Slack-line cableway excavators" are one of a family of older "low-tech" technologies called "Ropeways." Ropeways were used a lot on the US West Coast in the 19th century to move timber and agricultural products from land to "dogleg" schooners before the advent of motor vehicles. "Dogleg" schooners were a particuarly small and handy small ship type which could navigate really narrow passages to get close inshore at most any cliff area or inlet. A "dog's leg" is a nautical term for a particularly crooked, zig-zag, course with multiple tacks in a short distance. Please see the following on Aerial ropeways and cableways, plus railroad worktrains that utilized ropeway/cableway technology. 1) Aerial ropeways: automatic cargo transport for a bargain http://www.lowtechmagazine.com/2011/01/ ... sport.htmlTransport infrastructure
Ropeway towers could be constructed from timber or iron and were generally between 100 and 300 feet (30 to 90 metres) apart, although much longer spans were possible if necessary. In bicable ropeways the tension in the track cables was produced by weights applied at one of the terminal stations. However, in longer lines it became necessary to apply additional tension at intermediate points. For this purpose tension stations were built at distances of about 3000 to 6000 feet. The cars passed from one section of the cable to the next by means of intervening rails - so that no interruption occurred in the continuity of the track. This means that there are no limits to the length of a ropeway: each (longer) ropeway consisted of multiple sections that could be considered as separate ropeways. The same technique was applied to "angle stations", which were used to make a curve in a ropeway (tension stations and angle stations could be combined - see the illustration above, right). The largest drawback of an aerial tramway, also relevant today, is that it can only be built in a straight line. Every angle in a ropeway requires the erection of an angle station, which raises capital costs. However, in general, few angle stations are needed because ropeways can be constructed above most obstacles. Moreover, each tension and/or angle station can also double as a loading or unloading station. Goods could even be sent along different routes via a switch if more ropeways met at a single point. The picture above shows a ropeway switchyard of a German coal plant (described in a 1914 book) where three lines of carriers converge. To guard against the risk of accident from the premature discharge of a bucket or other cause when crossing public highways or railroads, wire nets were usually suspended between supports on either side, or structures especially erected for the purpose. An arrangement of a shelter bridge as required by a county council to hide the cableway where it passed over a public road can be seen on the right. and The many advantages of ropeways Why did aerial ropeways become so successful at the turn of the twentieth century? The main reason was that they were considerably cheaper than their alternatives, be it transport by horses and carts or transport by railroad. The ropeway was economical in operation and required only a minimal capital outlay. The investment that would be entailed in a hilly country by the necessity of making tunnels, cuttings and embarkments for a line or railway was avoided. A cableway could be constructed and worked on hilly ground at a cost not greatly exceeding that which would be called for on a level country. Rivers and ravines could be crossed without the aid of bridges. Gradients quite impractical to ordinary railroads could be worked with ease. One calculation showed that a ropeway only 1 mile (1,630 metres) long with a difference in altitude of 0.4 miles (645 meters), would require a railway of 15 miles (24 km) to reach the same point. Ropeways were also generally half as expensive to operate when compared to cartage by mules, horses, and oxen. Furthermore, an aerial tramway could be up and running in no time. Some lines could be easily moved from one place to another with comparative ease. An installation of 1 mile length at a beetroot farm in Holland, with a daily capacity of 50 tons, could be taken down and put up again in a fresh place in one day, by the aid of 20 men, provided the distance to cart the component materials did not exceed 5 miles. Ropeways continued to work during weather conditions that would bring surface hauling to a standstill (like floods or heavy snow, especially interesting in mountain areas) and they could be operated at night without hazards. Wear and tear were relatively low. Ropeways did not occupy any material quantity of ground, and the intervening land between posts could be left for cultivation or other use. Terminals could be arranged so that the material transported could be delivered at the exact spot where it was needed, saving all the expense of rehandling. One disadvantage thet ropeways had was that they were more vulnerable to high winds and electrical storms than other transportion options.2) Aerial Ropeways in Nepal http://www.notechmagazine.com/ropeways/3) Ropeway conveyor http://en.wikipedia.org/wiki/Ropeway_conveyorRopeway conveyor From Wikipedia, the free encyclopedia A ropeway conveyor or material ropeway[1] is essentially a subtype of gondola lift, from which containers for goods rather than passenger cars are suspended.
Ropeway conveyors are typically found around large mining concerns, and can be of considerable length. The COMILOG Cableway, which ran from Moanda in Gabon to Mbinda in the Republic of the Congo, was over 75 km in length. The Norsjö aerial tramway in Sweden had a length of 96 kilometers.
The world's first cable car on multiple supports was built by Adam Wybe in Gdańsk, Poland in 1644.
In Ethiopia the Italians built the Asmara-Massawa Cableway in 1936, which was 75 km long.
Conveyors can be powered by a wide variety of forms of energy, electric, engines, or gravity (particularly in mountainous mining concerns, or where running water is available).[2]4)History Friday: 81st ID’s Peleliu Lessons for MacArthur’s Invasion of Japan http://chicagoboyz.net/archives/38212.htmlThere were some good reasons the 81st ID thought of the Aerial Tramway at Peleliu. The US Army Corps of Engineers had used cableways and tramways as labor saving devices to build bridges, damns and water projects through out the American West for decades before WW2. It was, in the 1940′s, just one of the every day tools US Army Engineers thought of in the same way that today’s smart phone users today view the Internet. After WW2, particularly after the Korean War, helicopters replaced most applications of cableway and tramway technology inside the US Army. This is so long ago for the current US Army that in places like Afghanistan, where that technology would have been highly useful to relieve helicopter resupply of positions on high mountains, it just isn’t remembered.
The effect of these aerial tramway delivered sandbags was several fold. First, it took away much of the effectiveness of Japanese snipers and mortars, particularly their 50mm grenade dischargers, in producing a lot of American casualties.
Second, they gave American infantry a protected position to fight from with crew served heavy weapons (machine guns, mortars, light artillery) and artillery forward observers for Japanese counter attacks and infiltrations.
Third, it left American infantry _covered_ positions *closer* to Japanese positions to launch their “Blowtorch and corkscrew” flame/explosive attacks from. The 81st ID — unlike the 6th Marine Division at Sugar Loaf on Okinawa — didn’t have to cross the same ground over and over to get close enough to inflict attrition losses on underground Japanese positions. This was a very important development. At Biak, Leyte, Luzon, Tarawa, Saipan, Guam, Iwo Jima and Okinawa, flame thrower operators were dead men walking. This resulted in the U.S. Army’s Chemical Warfare Service having to train up a new generation of flamethrower operators for the next operation. This didn’t happen for the US Army after Peleliu. The 81st Infantry Division’s portable flamethrower operators actually survived the campaign. That was unheard of in Pacific Theater combat!
Last, when sand bag positions were placed around engineer roads for tanks and trucks, the 81st ID’s covered positions gave infantry close support to both the engineers and vehicles. Preventing the mining of those roads at night and allowing movement during the day. Thus allowing the application of huge “super-flame throwers” cobbled together from flame thrower guns, fire hoses, pump units and gasoline fuel trucks to flood out the largest multi-story “Cave Warfare” positions with thousands of gallons of fuel. What the 81st ID took on Peleliu was taken ONCE…and it stayed taken. That was the heart of what I call “Sandbag Constrictor” tactics.
It was absolutely certain that the 81st ID’s tramway and the sandbag “constrictor” tactics would have been used on Kyushu. 5) All About Work Trains http://www.railroad.net/articles/railfa ... orktrains/An early Illinois Central ditcher, X8001, is posed with its operating crew about 1912, copied by C. W. Witbeck from an old photograph. The bucket is positioned and dragged by the wooden beams. The near one, with the "ship's wheel" capstan, adjusts the angle of attack of the bucket, and also empties it.
A Chesapeake & Ohio ditching train. From left to right: Locomotive 6095, dump car AD35, flat car X2080 with crane D33, dump car AD36, caboose 3519, and Jordan spreader BS3. This consist is typical of trains used for drainage ditch maintenance, and also for building embankments and fills. This scene is at Marion, Indiana, on August 25, 1970. Photo by L. L. Davis.
A close view of an American Steam Ditcher in virtually as-built, if slightly battered, condition. Gulf Mobile & Ohio 66376 was found in this state at Meridian, Mississippi, on February 21, 1965. Note that the shovel chassis is chained to the flat car to prevent it from shifting in transit. Such a machine could be used as a crane by removing the dipper arm, and in fact nearly all the last surviving ditchers were so operated. Photo by John C. La Rue, Jr..
A typical crawler crane on a flatcar, which replaced the old American Ditchers. Reading crane R830 rests on its carrier car, 96610, at the Lehigh Street yards in Philadelphia, Pennsylvania, on December 28, 1974. Photo by John C. La Rue, Jr.
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