Route availability
From Wikipedia, the free encyclopedia
Route Availability is a system by which railway lines in the United Kingdom are graded. The system works on the principle of axle loads (and occasionally other factors), and is designed to stop locomotives with too high an axle load travelling over track which may be damaged by them.
In this system, each class of locomotive is allocated a route availability between one and ten, based primarily on the weight per axle. Each route is similarly allocated an RA number between 1 and 10. The rule is that no locomotive may work on track that has a lower route availability (RA) than it's own.
Contents |
[edit] Network Rail
Network Rail currently gives the allowed axle loadings as follows:[1]
| Route Availability | Axle Load |
|---|---|
| RA1–RA6 | ≤20.3 tonne |
| RA7-RA9 | ≤24.1 tonne |
| RA10 | ≤25.4 tonne |
| EU average | ≈22.5 tonne |
The information regarding route availability (RA) on this page comes from the British Rail (London Midland Region) Route Availability Guide, and the Freight Train Loads Book, both issued in 1969. It should be noted that several routes will have had their RA numbers changed since that time.
| Group Number | Mainline Classes | Shunters |
|---|---|---|
| 1 | Y14 | 01, 03, 04*, 11104, 15097 |
| 2 | 158 | 02$, 04*, 05 |
| 3 | ||
| 4 | 15, 16, 17, 22, 10800 | |
| 5 | 20, 23, 25, 27, 29, 31*, 37, 43, 55, 185 | 06, 08*, 09, 10, 11, 12 |
| 6 | 8K, D16/2, 24, 26, 31*, 33, 35, 40, 42, 47*, 48, 50, 52*, 53, 57, 71, 73, 81, 82, 83, 84, 85, 86, 87, 89 | 07, 08* |
| 7 | 44, 45, 46, 47*, 52*, 57, 58, 59, 66, 74, 91 | |
| 8 | 67, 76 | 13 |
| 9 | ||
| 10 |
* Depending on sub-class, see individual article for details. $ Discrepancy with original data.
[edit] Historical notes
Before nationalisation the Big Four railway companies had their own classification systems:
[edit] Great Western Railway
Each locomotive had a coloured disc painted on the cab side to indicate its route availability:
- uncoloured, lightest locomotives
- yellow disc
- blue disc
- red disc
- two red discs, heaviest locomotives
