Engineering

13 inches = 13/12 feet

area =pi(diameter)2 (1/4)

= pi(13/12)2(1/4)

= pi(169/144)(1/4)

=pi(42.25/144)

=.92175 square feet

Decalage on a fixed wing Biplane aircraft is the angle difference between the upper and lower wings of a fixed wing Biplane aircraft, i.e. the acute angle contained between the chords of the wings in question.

The decalage is said to be positive when the upper wing has a higher total angle-of incidence than the lower wing, and negative when its total angle of incidence is lower. Positive decalage results in greater lift from the upper wing than the lower wing, the difference increasing with the amount of decalage.

Uncle Fudd

British engineer George Stephenson (1781-1848) didn't invent the railway. Railways already existed, for transporting goods.

EARLY LIFE

It is interesting to note that George Stephenson's father was a steam engine keeper for the Wylam colliery in Northumbria. And the Stephenson's family home was right next door to the Wylam Wagonway, a five mile railway built in 1748. It had wooden rails on which horse-drawn wagons ran, transporting coal from the colliery to the River Tyne. Stationary steam engines were used to help pull loads up steep inclines.

Doubtless these accidents of birth had a major influence on what little George would do with his life.

THE COLLIERY

In 1804 someone at the Wylam colliery invented the STEAM LOCOMOTIVE, a form of engine that converted the pressure from a steaming boiler (a steam 'engine') into piston movement that made the whole engine move along, and thus becoming a steam 'locomotive.' But early attempts at using steam locomotives were fraught with difficulties, because the rails were still made of wood and couldn't successfully carry the weight of the steam locomotive.

RAILWAY SYSTEMS AND STEAM LOCOMOTIVES

At this time there were also only relatively short railway systems, laid to transport minerals in and from the mines. There was still no huge and interlinked networked railway system for steam locomotives. Furthermore, as wooden rails didn't seem such a good idea for carrying these heavy steam engines, George Stephenson was instrumental in designing and putting in place an IRON-RAIL SYSTEM. He also developed and improved on the idea of STEAM LOCOMOTIVES. In time, iron railway systems on which steam locomotives ran grew and became networked across the entire country.

STEPHENSON'S STEAM LOCOMOTIVES

George Stephenson built his first steam locomotive in 1813/1814. One of his later and much improved versions was called the Stephenson's Rocket. But it didn't go up, it went along. It could pull many more wagons of coal than a horse could, and was faster too!

THE PROBLEMS WITH HEAVY STEAM ENGINES

Meanwhile, Stephenson was still trying to improve the design of the iron rails, and how the engine sat on the rails, because the early iron rails were still breaking under the weight of the steam engines. But he worked out a way of spreading the load by (a) having the engine mounted on a series of wheels, and (b) creating strong springs for the wheels and axles, to cushion their impact on the rails.

By 1820 he had established the first stretch of rail that used no animal power whatsoever. It was 8 miles long, and went uphill and downhill and on the level. The steam locomotive was used for the uphill and level sections of the track, and the downhill sections worked by gravity.

STEAM ENGINES, NETWORKED RAILWAY SYSTEMS AND PASSENGER CARRIAGES

The following year (i.e. 1821) Stephenson was invited to look at Edward Pease's plans for a larger railway system, the Stockton and Darlington Railway. Stephenson suggested improvements to the plans, and went into business with Pease, making steam locomotives, the first one rolling off the production line in 1825. In due course they built a small PASSENGER CARRIAGE with train wheels so it could be pulled along the track behind their steam locomotive. They nicknamed the little carriage 'Experiment.' And it worked! And the inaugural trip became the first time that railway passengers had been pulled along solely by steam locomotive power on an iron rail track.

RAIL GAUGE

There were no standard widths for the distance between the pairs of railway lines. This made it very difficult to develop a wide area network of interlinking railway lines! George Stephenson gauged that a distance of 4 foot 8 1/2 inches (1435 mm) between the two lines would be ideal, and this became established as the national standard in the UK and has become widely adopted in many other countries.

AN UPHILL STRUGGLE

George Stephenson also noted that going uphill was harder for the steam locomotives than travelling downhill or on the level. In view of this he did his utmost to ensure that his trains ran on 'level' ground; achieving this by huge 'cuttings' and embankments along the routes where necessary. His signature 'Liverpool and Manchester Railway' (L&MR) system made its debut in 1830, and was hailed a 'resounding' success.

LIST OF STEPHENSON'S RAILWAY ACHIEVEMENTS

More efficient steam locomotives

e.g. (i) using multi-tube boilers, (ii) inclusion of a steam 'blast' jet into the engine to increase speed

'Level' and 'smooth' tracks

i.e. (i) tunnels, cuttings and embankments, + (ii) elimination of 'cog and pinion' tracks

More wheels on the locomotive

Linking the wheels, with driving rods directly connected to them, and coupling pairs of wheels to each other

Springed suspension

Improved iron rails

Flanged wheels

Standard gauge railway lines

Passenger carriages

The skew-arch bridge

Supplying the first steam locomotives to the United States

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