Route Availability (RA) is the system by which the permanent way and supporting works (bridges, embankments, etc.) of the National Rail network of Great Britain are graded. All routes are allocated an RA number between 1 and 10.
Rolling stock is also allocated an RA (again between 1 and 10) and the RA of a train is the highest RA of any of its elements. The RA is primarily related to the axle load of the vehicle, although axle spacing is also taken into consideration. In practice it is the locomotive which governs where trains may operate, although many high capacity 4 axle wagons have high RAs when fully loaded. (When considering the operation of trains the loading gauge must also be considered.)
Route Availability as a system was first devised by the London and North Eastern Railway, and perpetuated by British Rail to ascertain which locomotives can work on which lines throughout the rail network in Great Britain. The system uses numbers from 1 to 10 and a locomotive must have a route availability (RA) lower than or equal to the RA of a line to be allowed to work on the line.
Exemptions may be obtained to allow locomotives to operate on lines from which they may otherwise be banned. An exemption might be granted by placing a speed restriction over a weak bridge, for example.
Other articles related to "route availability, route":
... trials made by the Southern Railway on the prototype ascertained the eventual route availability of the class, so that they became a regular fixture on the restricted Tonbridge to ... Their route availability also meant that they were used on Central section trains to Portsmouth and Southampton until replaced by V class locomotives ... The U1 class worked troop trains along this route during the Second World War, proving their worth as rugged locomotives ...
Famous quotes containing the words availability and/or route:
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—Rutherford Birchard Hayes (18221893)
“A Route of Evanescence
With a revolving Wheel”
—Emily Dickinson (18301886)