(27 Apr 2014, 9:51 am)Andreos Constantopolous wrote Granted there may be other factors, such as traffic and loadings that contribute to late running, but the vehicle allocation will play a part too.
I mentioned the alx400 that was on the x1/x2 the other day - that was 30mins late at one point and had the following Gemini on its tail end.
When Tyresmoke had seen it earlier in the day, it was late - but not that far behind schedule.
As the day had gone on, there was obviously a reason it was falling later and later behind time.
Problem is the later and later you get, the more and more passengers you start picking up. It happens all the time on our 15s as an example, get 2 minutes late and before you know it you can be 7-8 late with the other one right behind you as he's been picking nobody up! Then the two start fighting and eventually fall behind til the next one catches up. This is why we regularly end up with pairs and sometimes 3s and 4s running around together when it's really busy (Wednesdays for example!).
Of course this is less of an issue on less frequent services but the same applies just over a longer time period. It's also harder to drop one out and get it back on time when you only have a half hourly frequency.