La configuración básica era la habitúal en este tipo de armas, con la cámara de combate situada en la parte delantera y el compartimento del motor en la trasera. La superestructura estaba constituida por planchas de blindaje inclinadas que alcanzaban un grosor máximo de ochenta milímetros en la coraza frontal. Este blindado tenía una altura total de tan solo ciento ochenta y cinco centímetros, lo que permitía su empleo con gran éxito en emboscadas. En orden de combate el peso era de veinticuatro toneladas, y la velocidad máxima 39 km/h. En los ejemplares de producción inicial se instaló en montaje de rótula el cañón Pak 39 L/48 de 7.5 cm con un mantelete tipo Saukopf de fundición. Hasta el final de la guerra y contando todos los ejemplares de las distintas versiones, se construyeron un total de 1.531 Jagdpanzer.
Saturday, December 12, 2009
iHobby is coming: The 25th annual iHobby Expo, a trade show for the hobby industry, is slated for Oct. 22-25 at the Donald E. Stephens Convention Center in Rosemont, I11., just outside Chicago. The show features model railroad manufacturers and vendors, as well as those in other hobbies such as radio control, plastic models, rockets, and die-cast metal toys. The expo is often a showplace for manufacturers to debut new hobby products. Model Railroader will have a full iHobby report on our Web site and in January's News & Products. For more information, go to www.ihobbyexpo.com. Modeler operates on a larger scale: United States Army officer and model railroader Leslie Parks had no idea his experience with small-scale trains would come in handy on the ground in Iraq. But when Parks was transferred to the Area of Operations that included the headquarters of Iraqi National Railways, his superiors assigned him to get it working. Parks, a Model Railroader reader, shared his experiences in an e-mail he sent to us. "In any sound prototype-based model railroad, you must have a purpose," Parks wrote. The Iraqi railroad was one of the largest employers in the area, but since its primary customer had been the former government, not much was moving on the rails.
at 1:48 AM
Dean Freytag's foundry article was published in two parts in the April and May 2009 issues. The prototype foundry, part of a small-engine plant, was fed by a pair of overhead cranes working on a craneway about a city block long. A single track ran just inside the concrete wall beneath the entire length of the craneway. That track was long enough to hold about a half-dozen 50-foot gondolas of scrap iron that were unloaded using electromagnets. The plant didn't have any visible means of moving freight cars, but I've seen similar size plants shift cars with a special electric windlass called a car puller. These devices have a cable that's hooked into one of the roping loops built into the corners of gondolas. Then the windlass can gradually pull the loaded car into position. Many manufacturing industries use a somewhat riskier practice of shoving cars with an industrial truck or forklift. The problem is how to stop the car once it's rolling. For model railroad operating purposes, I'd add a single spot with an unloading hopper under the track to receive a covered hopper of dry foundry sand at the very end of the long spur opposite the sand preparation building.
at 1:47 AM
Rotary beacons were initially used in the early 1960s to make switchers more visible in large yards at night. The flashing lights helped the vardmasters in the towers keep track of the switchers. In the 1970s, the Federal Railroad Administration began studying ways to reduce grade crossing accidents by making trains more visible to motorists. Tests with oscillating headlights, rotating beacons, alternating flashing lights, ditch lights, and roof-mounted strobe lights led to the use of a triangular combination of two strobe lights with a standard headlight or a pair of roof-mounted strobe lights. More FRA testing followed in the early 1990s to identify the most effective combination of a normal headlight with various secondary lights. In 1993, a triangular configuration with alternately flashing lower lights was field tested on CalTrans, Conrail, and Norfolk Southern. At the end of the tests, the FRA report lists an accident reduction of 76.4 percent on CalTrans, 74.3 percent on Conrail, and 54.6 percent on Norfolk Southern.
at 1:46 AM
Unit trains made up entirely of coal gondolas must be arranged with all of their rotary coupler ends facing the same direction for delivery to a rotary dumper. The rotary coupler ends are generally facing forward and coupled to the locomotive on loaded trains. In this manner, everything remains coupled and the dumping rotation occurs with the couplers aligned at the pivot point. Every pair of couplers must include a rotary coupler to pass through the dumper. If a car is reversed, two normal couplers will be together and the rotation will damage both cars. Even so, most of today's rotary car dumpers are sized to empty two cars at a time. Occasionally, a unit train car must be set out for repairs. It'll normally be picked up on the return trip of the car's original consist to maintain the proper car count. Since these trains often pass through a reverse loop at the dumper or the mine, occasionally cars end up facing the wrong way. However, the conductor delivering the loaded train is responsible for making sure all of its cars are oriented properly. Any odd ones are usually turned on a wye before the train leaves the yard.
at 1:45 AM