1946 Renumbering
The downside of the numbering system used by the LNER - and which had not been tackled by the 1942 renumbering - was that locomotives were carrying scattered numbers without reference to class, let alone type of locomotive. In 1943, a scheme was drawn up that would see a complete renumbering of the LNER stock, so that locomotives of the same class would be numbered together and placed in a series with classes of the same type. Due to the pressures of World War II, the scheme was not actually implemented until 1946, but the basic principles remained the same, as set out in the table below:
| Number Series | Locomotive Type | Principal Wheel Arrangements |
|---|---|---|
| 1-999 | Express passenger tender locomotives | 4-6-2, 2-8-2 and large 2-6-2 |
| 1000-1999 | Six-coupled passenger and mixed traffic tender locomotives | 4-6-0, 2-6-0 and small 2-6-2 |
| 2000-2999 | Four-coupled passenger tender locomotives | 4-4-0, 4-4-2 and 2-4-0 |
| 3000-3999 | Eight-coupled freight tender locomotives | 0-8-0, 2-8-0 and 2-8-2 |
| 4000-5999 | Six-coupled freight tender locomotives | 0-6-0 |
| 6000-6999 | Electric locomotives | Various types |
| 7000-7999 | Passenger tank locomotives | 2-4-2, 0-4-4, 4-4-2, 4-4-4 and 2-6-2 |
| 8000-8999 | Shunting tank locomotives (steam and diesel) | 0-4-0, 0-4-2 and 0-6-0 |
| 9000-9999 | Mixed traffic and freight tank locomotives | 0-6-2, 4-6-2 and other miscellaneous types |
| 10000 | Experimental Class W1 locomotive (retained 1923 number) | 4-6-4 |
In each class, individual engines were numbered in order of construction (with a small number of exceptions, most notably the 'A4' class where locomotives carrying the names of the LNER's directors were given 'significant numbers' 1-4).
Self-evidently the renumbering process was very complicated as the LNER was keen not to have two locomotives running in service with the same number. This meant renumbering engines whose new numbers were already vacant first and then following through the chain of renumberings.
There was a further complication in that part-way through the renumbering, there was a change of plan in terms of the numbers allocated in the 1-999 series (for reasons that are mostly unclear), the 1xxx series (to allow more space for new 'B1' class engines), and the 3xxx series (to allow more space for engines purchased from the War Department). This meant some of these engines were renumbered twice (106 in total - 59 of which were 'O1' or 'O4' engines). The changes were as follows:
| Class | Original Allocation | Revised Allocation |
|---|---|---|
| A1 | 500 | 113 |
| A3 | 501-578 | 35-112 (in order of original number, not age) |
| A4 | 580-613 (already changed so that 596/608/609/611 would be 1-4) | 1-4 (unchanged), 5-8 (prestigious people names), 9-13 (dominion names) and 14-34 (order of age) |
| V2 | 700-883 | 800-983 |
| A2 | 990-995 | 501-506 (plus new engines from 507 onwards) |
| B5 | 1300–1312 | 1678–1690 |
| B15 | 1313-1327 (8 survivors only) | 1691–1698 |
| B6 | 1328–1330 | 1346–1348 |
| B8 | 1331–1341 | 1349–1359 |
| B9 | 1342–1351 | 1469–1478 |
| B18 | 1470–1471 | 1479–1480 |
| B19 | 1472-1477 (4 survivors only) | 1490–1493 |
| B3 | 1480–1485 | 1494–1499 |
| B4 | 1490–1499 | 1481–1489 |
| O6 | 3100-3167 | 3500-3567 |
| O1 & O4 | 3500-3569 | Blanks between 3572-3809 (left vacant for engines loaned to the War Department but not returned) |
In addition, there were a number of other minor changes from the original plan where engines had since been withdrawn, but in these cases the numbers allocated under the new plan were carried from the start and no additional renumbering was required.
Read more about this topic: LNER Locomotive Numbering And Classification, Numbering