1.
Powerland Heritage Park
It is located in Brooks, United States, and is operated by the non-profit Antique Powerland Museum Association. It was initially established by a group of dedicated to the preservation and demonstration of steam powered equipment, antique farm machinery. The museum is located on a 62-acre parcel of land just off Interstate 5 in Brooks, the site was primarily used for threshing bees, a forerunner to the modern tractor pull, and the remainder of the site committed to farming. With the addition of a museum and a railroad museum, the entire grounds were dedicated to exhibits. Each summer, Antique Powerland presents the Great Oregon Steam-Up, wherein many of the exhibits are fired up, despite the name, many different types of power equipment are displayed, including steam-powered equipment, diesel-powered equipment, gasoline-powered equipment, and electric-powered equipment. Antique Powerland is structured as a collection of museums, some indoor and some outdoor, the various museums focus on different types of equipment, and have different exhibits on display.
Many of the exhibits are interactive, there are several operating trains on the property which visitors can ride, member museums, along with the equipment exhibited, Western Steam Friends Association. Branch 15- Early Day Gas Engines & Tractors Association, an organization which exhibits small engines and related farm implements. Displays large operating oil and gas engines, operates a large-scale model railroad on the site, with over 5,000 feet of trackage, which visitors can ride. Includes both gasoline and steam-powered engines, an association of John Deere enthusiasts, exhibits John Deere Tractors and implements, and operates a 3-acre wheat field on the premises. Operates Powerlands machine shop and blacksmith shop and operates the historic Brooks railroad depot, now relocated to the grounds of Powerland. An organization which preserves trucking history and vintage trucks, emphasizing trucking in the Pacific Northwest, a society dedicated to preserving the regional heritage of electric rail transportation.
The society operates the Oregon Electric Railway Museum at Powerland, Oregon Fire Service Museum and Learning Center. Established in 1993 to preserve the heritage of firefighting in Oregon, maintains a collection of antique fire engines of various vintage. Operates tractor pulls involving vintage tractors at the site, exhibits equipment manufactured by Caterpillar Inc. Willamette Valley Model Railroad Museum. A museum dedicated to model railroading, Northwest Vintage Car & Motorcycle Museum. A museum dedicated to the heritage of the automobile and motorcycle, among the exhibits is a replica of a 1930s Texaco service station. The Steam-Up includes events such as a parade of power equipment, sawmill demonstrations, demonstrations of using vintage equipment to harvest wheat
2.
Wildland fire engine
Most commonly used by the United States Forest Service, there are multiple types of wildfire apparatus which are used in different scenarios. Depending on where the engine is stationed it may carry as much as twice the standard in fire hose. In areas where there is rugged terrain that keeps engines from driving directly to the fire, in desert areas with moderate terrain, less hose is used as it is easier to access the fire. Often the technique of pump-and-roll is used where the vehicle drives with the pump engaged while a firefighter uses a hose to water on the fire. This technique allows a team of two to flank the perimeter of a fire, Wildland engines are traditionally smaller than standard fire engines and are primarily used for vegetation fires or wildland fires. They respond to emergencies in the country where traditional engines cannot respond. Most wildland engines feature four-wheel drive capability and can climb hills. In the fall of 2007, the National Wildfire Coordinating Group agreed on a set of standards for all engines that are used for wildland firefighting.
As structure engines are used on wildland fires, though primarily for structure protection. Per the standards there are 7 types of fire engines, the Type 3 Engines traditionally have four-wheel drive to make driving over rough terrain easier, they can be produced with standard rear wheel drive. Additionally the cab can either be 2-door or 4-door holding up to five people, almost all Type 3s have 4 doors as a crew size of five is optimum. Type 3s are required to have a minimum of 500 US gallons of water and they have a typical GVWR of 26,000 pounds. The Type 3 is the most popular engine in California due to the road access of most fires. The Type 4 engine trades a smaller pump and less hose for a 50% larger tank and they are required to carry a minimum of 750 US gallons of water, but only pump 50 US gallons per minute at a pressure of 100 pounds per square inch. The typical GVWR is at least 26,000 pounds, Type 5s are normally used as an initial attack engine atop a medium duty chassis. The GVWR of the chassis is around 20,000 pounds, Type 6 Engines are built on a pickup truck frame with a medium duty chassis giving a GVWR of 9, 000–16,000 pounds.
They are required to carry a minimum of 150 US gallons of water, in California these engines are staffed with one firefighter and used for patrols. Most other dispatch areas require the Type 6 to have a minimum of 3 personnel, Type 7s are patrol vehicles with a small pump and tank
3.
Four-wheel drive
Four-wheel drive, 4×4, and 4WD, is a form of drivetrain capable of providing power to all wheel ends of a two-axled vehicle simultaneously. It may be full-time, or on-demand, and is linked via a transfer case which provides an additional output drive-shaft. When a four-wheeled vehicle has power supplied to axles, this is described as all-wheel drive. However, four-wheel drive typically refers to a set of components and functions, and/or intended offroad application. 4×4/4WD/AWD systems were developed in different markets and used in many different vehicle platforms. There is no universally accepted set of terminology to describe the various architectures, the terms used by various manufactures often reflect marketing rather than engineering considerations or significant technical differences between systems. Four-by-four refers to the class of vehicles. The first figure represents the total wheels, and the second, syntactically, 4×2 means a four-wheel vehicle that transmits engine power to only two axle-ends, the front two in front-wheel drive or the rear two in rear-wheel drive.
Alternatively, a 6×4 vehicle has three axles, two of which power to two wheel ends each. Four wheel drive refers to vehicles with two axles providing power to four wheel ends, in the North American market the term generally refers to a system that is optimized for off-road driving conditions. The term 4WD is typically designated for vehicles equipped with a transfercase which switches between 2WD and 4WD operating modes, either manually or automatically. All wheel drive historically was synonymous with four-wheel drive on four-wheeled vehicles, and six-wheel drive on 6×6s, today in North America the term is applied to both heavy vehicles as well as light passenger vehicles. Typical AWD systems work well on all surfaces, but are not intended for more extreme off-road use, some all wheel drive electric vehicles solve this challenge using one motor for each axle, thereby eliminating a mechanical differential between the front and rear axles. An example of this is the dual motor variant of the Tesla Model S, individual-wheel drive was coined to identify those electric vehicles whereby each wheel is driven by its own individual electric motor.
This system essentially has inherent characteristics that would be attributed to four-wheel drive systems like the distribution of the available power to the wheels. However, because of the inherent characteristics of electric motors, torque can be negative, as seen in the Rimac Concept One and this can have drastic effects, as in better handling in tight corners. The term IWD can refer to a vehicle with any number of wheels, for example, the Mars rovers are 6-wheel IWD. Two wheels fixed to the same turn at the same speed as a vehicle goes around curves
4.
Trolleybuses in Dayton
The Dayton trolleybus system forms part of the public transportation network serving Dayton, in the state of Ohio, United States. One of only five such systems currently operating in the U. S, by the 1970s, Dayton was already the smallest U. S. city still operating a trolley bus system. For both of these reasons, the trolley buses are locally considered an icon of Dayton. Electric streetcar service in Dayton had started in 1888, and it continued through to, and indeed beyond, the last streetcar line in Dayton, City Railways route 1-Third Street, was converted to trolley buses on September 28,1947. The first trolley bus line in Dayton was opened by the Dayton Street Railway company, the impetus for the decision to adopt trolley buses was a 1932 fire at the companys carbarn, which gutted the building and destroyed 16 streetcars and two gas buses. In the late 19th century, it was common in the United States for cities to be served by multiple different streetcar companies, via mergers and sometimes bankruptcy the number of operating companies gradually declined to just one or two in each city.
By 1930, most U. S. cities had just one company providing all transit service. Dayton was unusual in having multiple transit companies in operation through to the World War II era, as late as the 1960s, transit service in Dayton was provided almost exclusively by trolley coaches. The table below lists all of Daytons trolley bus operators since the introduction of the mode in 1933, after 1955, all public transit in Dayton was operated by the City Transit Company. The transit system was transferred from private to public ownership on November 5,1972, MVRTA changed its name to the Greater Dayton Regional Transit Authority around May 2002. The name is shortened simply to RTA. The RTA voted to continue trolley bus operation, and in the replaced the aging fleet of Marmon-Herrington trolley buses with 64 Flyer E800 units. In the late 1980s, the Dayton trolley bus system was headed towards closure, ETI was a joint venture owned 65% by Skoda and 35% by the U. S. company, AAI Corporation. Trolley buses currently operate on seven RTA routes, since 1988, it has been the same seven routes, but with some changes made to the routings or service levels.
These are routes,1 East Third Street/West Third Street 2 Lexington/East 5th Street 3 Wayne Avenue 4 Hoover/Xenia-Linden 5 Valley Street/Far Hills 7 North Main/Watervliet 8 Salem/Lakeview, Daytons first trolley buses were supplied by the J. G. Brill Company, in 1933. Vehicles purchased included additional Brills, along with ETBs built by Pullman-Standard, Marmon-Herrington trolley buses thereby comprised almost the entire fleet at the time of transfer of the system to public ownership in 1972. A notable purchase of a trolley bus occurred in 1971. It was the first new trolley coach purchased by any U. S. transit system since 1955
5.
British Army
The British Army is the principal land warfare force of the United Kingdom. As of 2017 the British Army comprises just over 80,000 trained Regular, or full-time and just over 26,500 trained Reserve, or part-time personnel. Therefore, the UK Parliament approves the continued existence of the Army by passing an Armed Forces Act at least once every five years, day to day the Army comes under administration of the Ministry of Defence and is commanded by the Chief of the General Staff. Repeatedly emerging victorious from these decisive wars allowed Britain to influence world events with its policies and establish itself as one of the leading military. In 1660 the English and Irish monarchies were restored under Charles II, Charles favoured the foundation of a new army under royal control and began work towards its establishment by August 1660. The Royal Scots Army and the Irish Army were financed by the Parliament of Scotland, the order of seniority of the most senior line regiments in the British Army is based on the order of seniority in the English army.
At that time there was only one English regiment of dragoons, after William and Marys accession to the throne, England involved itself in the War of the Grand Alliance, primarily to prevent a French invasion restoring Marys father, James II. Spain, in the two centuries, had been the dominant global power, and the chief threat to Englands early transatlantic ambitions. The territorial ambitions of the French, led to the War of the Spanish Succession and the Napoleonic Wars. From the time of the end of the Seven Years War in 1763, Great Britain was the naval power. As had its predecessor, the English Army, the British Army fought the Kingdoms of Spain and the Netherlands for supremacy in North America and the West Indies. With native and provincial assistance, the Army conquered New France in the North American theatre of the Seven Years War, the British Army suffered defeat in the American War of Independence, losing the Thirteen Colonies but holding on to Canada. The British Army was heavily involved in the Napoleonic Wars and served in campaigns across Europe.
The war between the British and the First French Empire of Napoleon Bonaparte stretched around the world and at its peak, in 1813, the regular army contained over 250,000 men. A Coalition of Anglo-Dutch and Prussian Armies under the Duke of Wellington, the English had been involved, both politically and militarily, in Ireland since being given the Lordship of Ireland by the Pope in 1171. The campaign of the English republican Protector, Oliver Cromwell, involved uncompromising treatment of the Irish towns that had supported the Royalists during the English Civil War, the English Army stayed in Ireland primarily to suppress numerous Irish revolts and campaigns for independence. Having learnt from their experience in America, the British government sought a political solution, the British Army found itself fighting Irish rebels, both Protestant and Catholic, primarily in Ulster and Leinster in the 1798 rebellion. The Haldane Reforms of 1907 formally created the Territorial Force as the Armys volunteer reserve component by merging and reorganising the Volunteer Force, Great Britains dominance of the world had been challenged by numerous other powers, in the 20th century, most notably Germany
6.
Marmon-Herrington Armoured Car
The Marmon-Herrington Armoured Car was a series of armoured vehicles that were produced in South Africa and adopted by the British Army during the Second World War. In 1938 the South African authorities began funding development of a new armoured car for the Union Defence Force, the outbreak of the Second World War led to a vehicle based on a Ford 3-ton truck chassis. As South Africa lacked a developed industry, many components of the vehicle had to be imported. Final assembly was done by the branch of the Dorman Long company among others The first version. It was a wheelbase four wheeled chassis with drive to only one axle. It was armed with two Vickers machine guns, one in a turret and the other in the left hand side of the hull. There were two access doors in the rear. It saw an action against the Italian forces in the Western Desert. The Mk II had a shorter wheelbase than the Mark I and it was known in British service as Armoured Car, Marmon-Herrington Mk II. The Mark I continued in production while supply of parts from the United States was resolved, Mark II, Middle East Model denoted the vehicles serving with British forces in the North African campaign.
This variant was fitted with a Boys anti-tank rifle and a single coaxial Bren light machine gun, a second model intended for sub-Saharan deployments was armed with twin Vickers machine guns.7 cm Pak 36 and the 2.8 cm sPzB41 anti-tank guns. As the turret made no provision for armament, it was simply removed. Besides those cars utilised for reconnaissance, others were adopted for use as command posts, military ambulances, recovery vehicles. The Mark III was created with thicker armour plate on a compact body, more than 2,000 Mark IIIs were exported before production ceased in mid-1942. Some were dispatched to the Royal Netherlands East Indies Army and arrived during the East Indies Campaign, a number were captured by invading Japanese forces in March 1942. In March 1943 a completely redesigned Mk IV/Mk IVF entered production and it was a monocoque with rear-mounted engine and a turret-mounted 2 pounder with a coaxial 0.3 in Browning machine gun as the standard armament. Due to the inability of Marmon-Herrington to supply sufficient drivetrains, the F used a Canadian Ford drive train, further versions were designed but never got beyond the prototype stage.
In total,5,746 Marmon-Herrington Armoured Cars were built, about 4,500 were used by South African units, while others were employed by British, New Zealand, Free French, Dutch East Indies and Belgian forces
7.
Truck
A truck is a motor vehicle designed to transport cargo. Trucks vary greatly in size and configuration, smaller varieties may be similar to some automobiles. Commercial trucks can be large and powerful, and may be configured to mount specialized equipment, such as in the case of fire trucks and concrete mixers. Modern trucks are powered by diesel engines, although small to medium size trucks with gasoline engines exist in the US. In the European Union, vehicles with a gross mass of up to 3.5 t are known as light commercial vehicles. Trucks and cars have an ancestor, the steam-powered fardier Nicolas-Joseph Cugnot built in 1769. However, steam wagons were not common until the mid-1800s, the roads of the time, built for horse and carriages, limited these vehicles to very short hauls, usually from a factory to the nearest railway station. The first semi-trailer appeared in 1881, towed by a tractor manufactured by De Dion-Bouton. In 1895 Karl Benz designed and built the first truck in history using the internal combustion engine, that year some of Benzs trucks were modified to become the first bus by the Netphener, the first motorbus company in history.
A year later, in 1896, another internal combustion engine truck was built by Gottlieb Daimler, other companies, such as Peugeot, Renault and Büssing, built their own versions. The first truck in the United States was built by Autocar in 1899 and was available with optional 5 or 8 horsepower motors, trucks of the era mostly used two-cylinder engines and had a carrying capacity of 3,300 to 4,400 lb. In 1904,700 heavy trucks were built in the United States,1000 in 1907,6000 in 1910, after World War I, several advances were made, pneumatic tires replaced the previously common full rubber versions. Electric starters, power brakes,4,6, and 8 cylinder engines, closed cabs, the first modern semi-trailer trucks appeared. Touring car builders such as Ford and Renault entered the heavy truck market, although it had been invented in 1890, the diesel engine was not common in trucks in Europe until the 1930s. In the United States, it took longer for diesel engines to be accepted. The word truck might come from a back-formation of truckle, meaning small wheel or pulley, from Middle English trokell, another possible source is the Latin trochus, meaning iron hoop.
In turn, both sources emanate from the Greek trokhos, meaning wheel, from trekhein, the first known usage of truck was in 1611, when it referred to the small strong wheels on ships cannon carriages. In its extended usage it came to refer to carts for carrying heavy loads and its expanded application to motor-powered load carrier has been in usage since 1930, shortened from motor truck, which dates back to 1901
8.
Louisville, Kentucky
Louisville is the largest city in the Commonwealth of Kentucky and the 30th-most populous city in the United States. It is one of two cities in Kentucky designated as first-class, the other being the states second-largest city of Lexington, Louisville is the historical seat and, since 2003, the nominal seat of Jefferson County. Louisville was founded in 1778 by George Rogers Clark and is named after King Louis XVI of France, making Louisville one of the oldest cities west of the Appalachian Mountains. Sited beside the Falls of the Ohio, the major obstruction to river traffic between the upper Ohio River and the Gulf of Mexico, the settlement first grew as a portage site. It was the city of the Louisville and Nashville Railroad. Its main airport is the site of United Parcel Services worldwide air hub, since 2003, Louisvilles borders have been the same as those of Jefferson County because of a city-county merger. The official name of this consolidated city-county government is the Louisville/Jefferson County Metro Government, the citys total consolidated population as of the 2014 census estimate was 760,026.
However, the total of 612,780 excludes other incorporated places and semiautonomous towns within the county and is the population listed in most sources. As of 2014, the MSA had a population of 1,269,702, the history of Louisville spans hundreds of years, and has been influenced by the areas geography and location. The rapids at the Falls of the Ohio created a barrier to river travel, the first European settlement in the vicinity of modern-day Louisville was on Corn Island in 1778 by Col. George Rogers Clark, credited as the founder of Louisville. Several landmarks in the community are named after him, two years later, in 1780, the Virginia General Assembly approved the town charter of Louisville. The city was named in honor of King Louis XVI of France, early residents lived in forts to protect themselves from Indian raids, but moved out by the late 1780s. In 1803, explorers Meriwether Lewis and William Clark organized their expedition across America in the town of Clarksville, Indiana at the present-day Falls of the Ohio opposite Louisville, Kentucky.
The citys early growth was influenced by the fact river boats had to be unloaded and moved downriver before reaching the falls. By 1828, the population had swelled to 7,000, the city grew rapidly in its formative years. Louisville was a shipping port and slaves worked in a variety of associated trades. The city was often a point of escape for slaves to the north, during the Civil War, Louisville was a major stronghold of Union forces, which kept Kentucky firmly in the Union. It was the center of planning, supplies and transportation for numerous campaigns, by the end of the war, Louisville had not been attacked, although skirmishes and battles, including the battles of Perryville and Corydon, took place nearby
9.
Monocoque
Monocoque, structural skin, is a structural system where loads are supported through an objects external skin, similar to an egg shell. The word monocoque is a French term for single shell or single hull, a true monocoque carries both tensile and compressive forces within the skin and can be recognised by the absence of a load carrying internal frame. By contrast, a semi-monocoque is a combining a tensile stressed skin. Other semi-monocoques not to be confused with true monocoques include vehicle unibodies, which tend to be composites, early aircraft were constructed using frames, typically of wood or steel tubing, which could be covered with fabric such as irish linen or cotton. The skin added nothing to the strength of the airframe and was dead weight beyond providing a smooth sealed surface. This reduced drag so effectively it was able to win most of the races it was entered into, however, it was prone to damage from moisture and delamination. While all metal aircraft from the Junkers firm had appeared as early as 1915, the first metal monocoques were built by Claudius Dornier, while working for Zeppelin-Lindau.
After failed attempts with several large flying boats in which a few components were monocoques, the aluminum alloy monocoque chassis was first used in the 1962 Lotus 25 Formula 1 race car. The term monocoque is frequently misused when referring to unibody cars, in motor racing, the safety of the driver depends on the car body which must meet stringent regulations and a few cars have been built with monocoque structures. Tanks and other armored vehicles such as the German Fuchs 2 and this reduces weight for a given amount of armor compared to vehicles to which armor has been attached to an underlying frame. A monocoque-framed motorcycle was developed by the Spanish motorcycle manufacturer, Ossa won four Grand Prix races with the monocoque bike before their rider was killed during the 1970 Isle of Man TT, causing the Ossa factory to withdraw from Grand Prix competition. Notable designers such as Eric Offenstadt and Dan Hanebrink created unique monocoque designs in the early 1970s, the 1973 Isle of Man TT was won by Peter Williams on the monocoque-framed Norton John Player Special that he helped design.
Honda experimented with a monocoque Grand Prix racing motorcycle named the NR500 in 1979, in 1987 John Britten developed the Aero-D One, featuring a composite monocoque chassis that weighed only 12 kg. The first time an aluminium monocoque frame appeared on a production motorcycle was the 2000 Kawasaki Ninja ZX-12R. This was Kawasakis flagship production sportbike aimed at being the fastest production motorcycle, various rockets have used pressure-stabilized monocoque designs, such as Atlas and Falcon 1. Balloon tanks are not true monocoques but act in the way as inflatable shells. A balloon tank skin only handles tensile forces while compression is resisted by internal pressure in a way similar to semi-monocoques braced by a solid frame. This becomes obvious when internal pressure is lost and the structure collapses, the Handle is an electric guitar characterized by its hollow sectioned monocoque chassis, created by the award-winning designer Peter Solomon
10.
North African Campaign
The North African Campaign of the Second World War took place in North Africa from 10 June 1940 to 13 May 1943. It included campaigns fought in the Libyan and Egyptian deserts and in Morocco, the campaign was fought between the Allies and Axis powers, many of whom had colonial interests in Africa dating from the late 19th century. The Allied war effort was dominated by the British Commonwealth and exiles from German-occupied Europe, the United States entered the war in December 1941 and began direct military assistance in North Africa on 11 May 1942. Fighting in North Africa started with the Italian declaration of war on 10 June 1940, on 14 June, the British Armys 11th Hussars crossed the border from Egypt into Libya and captured the Italian Fort Capuzzo. Information gleaned via British Ultra code-breaking intelligence proved critical to Allied success in North Africa, victory for the Allies in this campaign immediately led to the Italian Campaign, which culminated in the downfall of the fascist government in Italy and the elimination of a German ally.
On 10 May 1940, the Wehrmacht had started the Battle of France, one month later, it was plain to see that France would have to surrender within two weeks. On 10 June 1940, the Kingdom of Italy aligned itself with Nazi Germany and declared war upon France, British forces based in Egypt were ordered to undertake defensive measures, but to act as non-provocatively as possible. However, on 11 June they began a series of raids against Italian positions in Libya, following the defeat of France on 25 June, Italian forces in Tripolitania—facing French troops based in Tunisia—redeployed to Cyrenaica to reinforce the Italian Tenth Army. Italian dictator Benito Mussolini ordered the Tenth Army to invade Egypt by 8 August, two days later, no invasion having been launched, Mussolini ordered Marshal Graziani that, the moment German forces launched Operation Sea Lion, he was to attack. The battle plan was to advance along the road, while limited armoured forces operated on the desert flank. To counter the Italian advance, Wavell ordered his forces to harass the advancing Italians, falling back towards Mersa Matruh.
Positioned on the flank was the 7th Armoured Division, which would strike the flank of the Italian force. By 16 September, the Italian force had advanced to Maktila, around 80 mi west of Mersa Matruh, in response to the dispersed Italian camps, the British planned a limited five-day attack, Operation Compass, to strike at these fortified camps one by one. The British Commonwealth force, totalling 36,000 men, attacked the forward elements of the 10-division-strong Italian army on 9 December, following their initial success, the forces of Operation Compass pursued the retreating Italian forces. In January, the port at Bardia was taken, soon followed by the seizure of the fortified port of Tobruk. Some 40,000 Italians were captured in and around the two ports, with the remainder of the Tenth Army retreating along the coast road back to El Agheila. Richard OConnor sent the 7th Armoured Division across the desert, with a reconnaissance group reaching Beda Fomm some ninety minutes before the Italians.
Although desperate attempts were made to overcome the British force at the Battle of Beda Fomm, the Italians were unable to break through, and the remnants of the retreating army surrendered
11.
Trolleybuses in San Francisco
The San Francisco trolleybus system forms part of the public transportation network serving San Francisco, in the state of California, United States. Opened on October 6,1935, it presently comprises 15 lines, in San Francisco, these vehicles are known as trolley coaches. One of only five such systems currently operating in the U. S. the Muni trolley bus system is the second-largest such system in the Western Hemisphere, a particularly notable feature of its operations are very steep grades. The Muni trolley bus system is complementary to the citys rail-bound Caltrain, Bay Area Rapid Transit, Muni Metro, in addition, it shares some of its overhead wires with the F Market & Wharves streetcar line. Of the latter,40 were New Flyer E60 vehicles,12 of these were retired in early 2013, and the remaining 28 were retired in early January 2015. All of the then-remaining 273 trolleybuses were built by Electric Transit, Inc. mostly in 2001–03, the 240 40-foot units being model 14TrSF, an order was placed in 2014 for 60 New Flyer XT60 articulated vehicles, the systems first low-floor trolleybuses.
Two prototypes arrived in March 2015 and May 2015, delivery of the 58 production-series vehicles began in September 2015, and the series entered service between November 2015 and July 2016. They replaced the 33 ETI 15TrSF articulated trolleybuses, the last of which were retired in April–May 2016 and these changes left the current fleet with the 240 conventional units built by ETI and 60 New Flyer XT60s. The articulated trolleybuses are used on the 5R,14 and 30S lines, the suffix SF in the two ETI model numbers stands for San Francisco. These two types were specially derived from the standard series Škoda 14Tr for use on the Muni system, the model XT60 for New Flyer has prefixes X for Xcelsior and T for electric, and the suffix 60 for the 60-foot bus. The first order to be placed under the 2013 agreement was the 2014 order for 60 articulated trolleybuses, San Francisco Municipal Railway fleet List of trolleybus systems in the United States Perles, with John McKane, Tom Matoff, Peter Straus.
The Peoples Railway, The History of the Municipal Railway in San Francisco, San Francisco database / photo gallery and San Francisco trolleybus list at Urban Electric Transit – in various languages, including English
12.
Steering
Steering is the collection of components, etc. which allows any vehicle to follow the desired course. An exception is the case of transport by which rail tracks combined together with railroad switches provide the steering function. The primary purpose of the system is to allow the driver to guide the vehicle. Other arrangements are found on different types of vehicles, for example. The basic aim of steering is to ensure that the wheels are pointing in the desired directions and this is typically achieved by a series of linkages, rods and gears. The angle the wheels make with the plane influences steering dynamics as do the tires. The rack and pinion design has the advantages of a degree of feedback. A disadvantage is that it is not adjustable, so that when it does wear and develop lash, BMW began to use rack and pinion steering systems in the 1930s, and many other European manufacturers adopted the technology. American automakers adopted rack and pinion steering beginning with the 1974 Ford Pinto, older designs use two main principles, the worm and sector design and the screw and nut.
Both types were enhanced by reducing the friction, for screw and nut it is the ball mechanism. The steering column turns a large screw which meshes with nut by recirculating balls and this design is still in use in trucks and other large vehicles, where rapidity of steering and direct feel are less important than robustness and mechanical advantage. The worm and sector was a design, used for example in Willys and Chrysler vehicles. To reduce friction the sector is replaced by a roller or rotating pins on the rocker shaft arm, other systems for steering exist, but are uncommon on road vehicles. Power steering helps the driver of a vehicle to steer by directing some of its power to assist in swiveling the steered road wheels about their steering axes. To alleviate this auto makers have developed power steering systems, or more correctly power-assisted steering, there are two types of power steering systems and electric/electronic. A hydraulic-electric hybrid system is possible, a hydraulic power steering uses hydraulic pressure supplied by an engine-driven pump to assist the motion of turning the steering wheel.
In EPS, the amount of assistance is easily tunable to the type, road speed. An added benefit is the elimination of environmental hazard posed by leakage, an outgrowth of power steering is speed sensitive steering, where the steering is heavily assisted at low speed and lightly assisted at high speed
