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For a discussion about cycles go to the Cycles page
Transport systems may be classified into three main groups according to the load they normally carry: passenger, freight, and military. Some are shared by more than one of these groups; for example during the war some passenger ships were used for troop and weaponry transport, and trains carry both passengers and freight.
We have at our disposal a variety of transport systems for use over land, sea and air - and, although still in its infancy, into space.
Each of these has its advantages and disadvantages, depending on its application.
Aircraft can travel over both land and sea and access places that are difficult or impossible to reach by other means, very quickly.
Ships are much slower and are more limited in their access but can carry enormous loads.
Rail services can also handle heavy loads, but are limited to accessing places to which rail lines have been provided.
Road transport is very flexible and can handle reasonably heavy roads, but delivery at times may be slow or unreliable due to traffic and other conditions.
Each of these systems has undergone changes over the years, and some of these changes will be discusssed here.
Road transport vehicles have changed immensely since the '40s. Cars are much faster, more comfortable, safer, and have many features that were never dreamed of back then. Trucks and buses carry much greater
loads, and other forms, like cycles and scooters are barely recognizable as descendants of the older ones.
Even our stations and bus stops are unrecognizable from those of our youth.
Roads are the oldest and by far the largest of the transport systems, and allow personal travel (pedestrian, cycle and car), community travel (buses and coaches),
and service travel (emergency, commercial and heavy goods vehicles).
As roads became more numerous, and traffic speed and numbers increased, ways were invented to make road traffic safer and more convenient.
One of these was the prioritising of roads, with highway and super-highway traffic being allowed unimpeded access, while intercepting-road traffic was obliged to give them right-of-way. Lesser roads were controlled by various signs indicating their need to stop or slow down to allow major-road traffic to pass. Traffic lights were invented in 1912, using only red and green indicators. Since then, several systems have been used at various times. All allow for a "preparation time" when drivers are cautioned, usually by a yellow or amber light, that the lights are about to change from green to red or vice-versa. In some areas, a clock-face type of indicator was used, where a sweep-hand rotated over a face with red, yellow and green segments. Roundabouts, with a central unused area, are often used instead of traffic indicators where traffic is light. These allow traffic in all directions to pass unimpeded if no other traffic is present. Many other signs are used to warn of dangerous sections, and speed limits are imposed according to the area through which the road passes.
Road surfaces tend to become slippery at times from oil or chemical spills, loose gravel or sand, or rain or ice, causing braking problems for vehicles. Various methods have been used to reduce this problem. Salt is sometimes applied to icy road surfaces, to melt the ice. Road surfaces are given a "camber" or slope to the sides to allow water to drain away. Road surface materials that give better braking assistance are used.
For information about trains, goto the Trains page, or to see some famous old trains, go to the Steam Trains page. For explanations of some of the terminology related to trains, see the Train Terminology page.
Since mechanised railways first appeared in the early 20th century, there have been significant changes in their design, construction and function.
Rail tracks have both advantages and disadvantages over road tansport. The most obvious disadvantage is that the vehicles are confined to
points along the rail route, and other points must be serviced by alternative means - most often buses for passengers, trucks for freight.
Another, associated problem is that if there is a breakdown or accident on the track, the route is unusable for some time. This is often remedied by trains travelling from both directions to their nearest access point, swapping loads and returning along their own secion.
A big advantage is that much heavier loads can be transferred quickly and securely from point to point. Rails can be more readily examined and maintained than roads due to their structure and defined routes.
Some of the problems in designing and building railways are
- The immense weight of rail traffic being supported by the rails means their foundation must be extremely solid and stable.
- While travelling, a train is constantly adjusting its path, oscillating between the two rails. This, as well as curves in the track, places a huge lateral strain and wear on the rails, so the sleeper-system must control this.
- Rises and falls in the terrain may need to be dealt with by tunneling or bridging, as the impact of a train on the track at any rise places huge stress on the rails, and falls in levels increase the risk of "floating" and possible derailment.
- The length of rolling stock - for example passenger carriages - means that they need wide curves where changes in track direction occur. For this reason "bogeys" of four, or sometimes six or eight wheels, are placed at each end of the carriage. But this has the effect of concentrating the weight of the load at these points.
- Heat causes expansion in metals, and as the rails expand in hot weather their length increases, which could cause the rails to buckle. A small gap is left between lengths of rail to accommodate this. This gap is also a source for impact between the wheel and the rail.
Ships today are vastly different and there are many more types than in my younger days.
Modern warships are immensely powerful, with nuclear warheads, rockets that follow changes in a target's location, and aircraft that deploy to protect the ship or other items.
Cruise ships carry thousands of passsengers in absolute luxury, with shops, theatres and swimming pools now the norm, rather than the exception.
Dedicated Service vessels are used to lay and maintain undersea cables, transport oil and other cargo between countries, search for and rescue passengers and crew of other vessels, and perform many more functions.
To see more on this, go to the Ships page.
Recent Related News
Qantas will begin daily non-stop flights between Perth and London, a trip of 14498 km, on its new Boeing 787 Dreamliner from March 24, 2018. With its swept-back wings and unique motor shape, it looks impressively
streamlined and futuristic.
In 1947, the trip took four days, with nine stops on the way. With the 787 it will take 17 hours - average speed 852kph - with no intermediate stops, due largely to its using 20 per cent less fuel than similarly sized aircraft.
Cost of the trip (one way, economy, on March 25 2018) ) will be $1782.39, but cost will fluctuate with market changes. Today, the trip on a "normal" plane would cost $1886, so it's quite comparable.
Passenger comfort has obviously been a priority with Qantas in designing these flights: The Dreamliner will feature 236 seats - less than most other aircraft of its type; windows are 65 per cent larger than comparable aircraft windows; and there is a huge amount of on-board entertainment and larger luggage space.
Not only will Dreamliner provide convenient transport between Perth and the UK, but it will greatly increase tourism between Perth and Europe and Australia's Eastern states.
The Wright brothers made the first powered flight in 1903. They could never have dreamed of the technology applied to flight now.
The first practical radar was built in 1935, but at the time it was used in meteorological, not aircraft applications.
Jet engines were invented in 1937, and the first jet-propelled flight was made in 1939 in the Heinkel HE178. This was the same year that the first helicopter, the VS300 was built.
Although aircraft had been used for some time in warfare situations, the 1945 invention of nuclear bombs increased the strategic importance of military aircraft. Even a moderate fleet of long-range bombers could deliver a deadly blow to the enemy.
During World War 2, Radio Detection and Ranging (RADAR) and Instrument Landing Systems (ILS) were both used in aircraft for the first time, and the Messerschmitt ME262 jet fighter, the Flying Fortress and Superfortress high altitude heavy bombers were made and played a very important part in the war.
The sound barrier (mach 1, approx 767 MPH) was broken for the first time in 1947.
The Boeing 377 Stratocruiser was a large long-range airliner, first flown on July 8, 1947. Its design included two passenger decks and a pressurized cabin, a relatively new feature on transport aircraft. It could carry up to 100 passengers on the main deck plus 14 in the lower deck lounge.
In 1949 the De Haviland Comet, the first commercial jet aircraft, appeared. It had four turbojet engines, a pressurised fuselage, and large square windows. For the era, it offered a relatively quiet, comfortable passenger cabin, and in 1952 it was used for regular passenger flights between London and South Africa.
In 1953 the Learjet 23 became the first small jet aircraft to enter mass production, powered by 2 turbojet engines and capable of carrying 5 passengers plus 2 crew.
In 1969, the Boeing 747 became the first wide-bodied passenger plane. It used turbofan combustion".
The Concorde jet arrived in 1976, and was capable of carrying 100 passengers at over 1500 MPH, or mach 2. But a serious accident in 2000 and its subsequent grounding for about a year, coupled with high maintenance costs, led to its decommissioning in 2003.
The F117 Nighthawk Stealth fighter, at right, was introduced in 1983, and retired in 2008. It has a top speed of 993 km/h (mach 0.92) and a range of 1720 km. The B2 Flying Wing bomber was built in the '90s. Pictured at left the B-2 Spirit (1997) has a top speed of 1,010 km/h and a range of over 11000 km. Both were designed to be invisible to radar and other systems, using a system called Stealth Technology. Changes to aircraft shape and surface composition are a major part of stealth technology, and both are used extensively by several countries now.
Supersonic interceptor aircraft were used for a time, but by 1955 attention shifted to guided surface-to-air missiles. Then once again, a new technology was needed when a new type of nuclear-carrying platform, the intercontinental ballistic missile (ICBM) appeared. This signalled the start of the Space Race between the nations.
Aeroflot, of The USSR, was the first airline in the world to operate sustained regular jet services in 1956 with the Tupolev Tu-104 (81 passengers). The American Boeing 707 and DC-8 (both from 140 to 219 passengers) followed in 1958, establishing new levels of comfort and safety. This ushered in the age of mass commercial air travel, the Jet Age.
The Boeing 747 ("Jumbo"), first flown in 1970, was at the time the largest commercial passenger aircraft ever to fly, capable of carrrying 660 passengers, but was superseded by the Airbus A380, which is capable of carrying up to 853 passengers.
In 1975 Aeroflot introduced the first supersonic passenger plane, the Tu-144, and in 1976 British Airways and Air France began supersonic service across the Atlantic with Concorde.
The last quarter of the 20th century saw a change of emphasis, from flight speeds, distances and materials technology to digital applications in both flight avionics, and aircraft design and manufacturing techniques.
Digital "fly-by-wire" systems use computer-techmology to interpret the commands given by the pilot, and apply them to the controls. They are also capable of checking to ensure that the commands will not cause unrecoverable state of flight for the plane, and of initiating control commands without the need for pilot action. Digital technology also allowed subsonic military aviation to begin eliminating the pilot in favor of remotely operated or completely autonomous unmanned aerial vehicles (UAVs).
In October 2003 the first totally autonomous flight across the Atlantic by a computer-controlled model aircraft was performed. UAVs are now an established feature of modern warfare.