GWR 811A21
View line GWR
Alerts for train 811A21
Alerts are saved per line, not per trip id, so they keep working when the operator changes the timetable. This train runs on line GWR.
The mini-map returns when the train runs
On-time · 30 days
33%
8/24 runs under 3 min
RT coverage: 24 full · 0 partial · 0 no data
On-time · 90 days
33%
26/79 runs under 3 min
RT coverage: 79 full · 0 partial · 0 no data
Typical delay
+4min
Median at arrival, 90 days
30 days: +5 min
P90
+18min
9 in 10 runs arrive with less than this
30 days: +15 min
Last 30 days
Delay at the end of each run, in minutes. One bar per run.
- On time (<3 min)
- 3–10 min
- 10–30 min
- 30+ min
- Partial coverage
- No data
Worst days
- Wed 23 Sept Max en route +36 min · last fix heading to 74331 +36 min
- Sun 20 Sept Max en route +28 min · last fix heading to 73251 +28 min
- Tue 27 Oct Max en route +27 min · last fix heading to Maidenhead +27 min
- Wed 19 Aug Max en route +27 min · last fix heading to 73251 +27 min
- Thu 13 Aug Max en route +24 min · last fix heading to 73251 +24 min
Distribution · 90 days
79 runs with a known final delay. On time = under 3 min, the same cut the map uses.
- Early 1% · 1
- On time 32% · 25
- 3–10 min 44% · 35
- 10–30 min 22% · 17
- 30+ min 1% · 1
On-time by weekday
- 20% M n=10
- 58% T n=12
- 25% W n=12
- 33% T n=12
- 36% F n=11
- 36% S n=11
- 18% S n=11
Recent runs
| Date | Last stop | Final | Max |
|---|---|---|---|
| Sat 7 Nov | Maidenhead 14:35 | 0 min | +4 min |
| Fri 6 Nov | Slough 14:37 | +2 min | +2 min |
| Thu 5 Nov | Slough 14:49 | +12 min | +13 min |
| Wed 4 Nov | Slough 14:44 | +9 min | +9 min |
| Tue 3 Nov | Slough 14:39 | +4 min | +4 min |
| Mon 2 Nov | Slough 14:34 | −2 min | — |
| Sun 1 Nov | Maidenhead 16:21 | +3 min | +3 min |
| Sat 31 Oct | Slough 14:48 | +5 min | +5 min |
| Fri 30 Oct | Slough 14:48 | +5 min | +5 min |
| Thu 29 Oct | Slough 14:47 | +4 min | +4 min |
| Wed 28 Oct | Slough 14:45 | +2 min | +2 min |
| Tue 27 Oct | Maidenhead 15:10 | +27 min | +27 min |
| Mon 26 Oct | Slough 15:01 | +18 min | +18 min |
| Sun 25 Oct | Maidenhead 16:18 | +3 min | +4 min |
| Sat 24 Oct | Slough 14:53 | +10 min | +12 min |
| Fri 23 Oct | Slough 15:00 | +17 min | +17 min |
| Thu 22 Oct | Maidenhead 14:48 | +5 min | +5 min |
| Wed 21 Oct | Maidenhead 14:51 | +8 min | +8 min |
| Tue 20 Oct | Maidenhead 14:45 | +1 min | +5 min |
| Mon 19 Oct | Slough 14:43 | 0 min | — |
| Sun 18 Oct | Maidenhead 16:23 | +5 min | +9 min |
| Sat 17 Oct | Slough 14:43 | 0 min | — |
| Sun 11 Oct | Slough 16:13 | 0 min | +1 min |
| Sat 10 Oct | Maidenhead 14:50 | +7 min | +8 min |
| Fri 9 Oct | Slough 14:46 | +3 min | +3 min |
| Thu 8 Oct | Maidenhead 14:44 | +1 min | +2 min |
| Wed 7 Oct | Slough 14:46 | +3 min | +3 min |
| Tue 6 Oct | Maidenhead 14:45 | +2 min | +4 min |
| Mon 5 Oct | Slough 14:47 | +4 min | +4 min |
| Sun 4 Oct | 73251 16:16 | +3 min | +5 min |
Each run is closed into train_runs (country, train number, service day) from the live positions. Final delay = last delay seen. Partial coverage: the feed stopped before the final stop (last value used, hatched in the chart). No data: a run without any valid delay; counts as neither on time nor late. Data collected since 11 July 2026.