1NEEDS2POST wrote: ↑Fri Apr 26, 2019 5:37 pm
Why do we bother with different stopping patterns on the Gawler line? In my opinion, all trains should be all stops, including North Adelaide. Let's see why.
All stops trains, including North Adelaide, take 56 minutes to travel from Gawler to Adelaide. During the day, most trains follow one of two stopping patterns. Pattern A trains will stop at half of the small stations, pattern B will stop at the other half. Travel times from Gawler to Adelaide are:
Pattern A: 52 minutes
Pattern B: 50 minutes
At 7:51 on Weekdays, there is a non-stop train from Adelaide to Salisbury. It takes 21 minutes. Compare to all-stops at 29 minutes. This a larger saving, but there are other big stations in between that this train skips.
My point is that there is not much time saving with skipping small stations. For people at the small stations, during the day, their frequency gets cut to once every half an hour. At the big stations, the frequency is once every 15 minutes.
So the average wait is 15 minutes at the small stations and 7.5 minutes at the big stations. Average journey time from Gawler to Adelaide during the day is:
(Pattern A + Pattern B)/2 + Average wait
(52 + 50)/2 + 7.5 = 58.5 minutes
But for say, Ovingham to Adelaide during the day is:
Pattern A + Average wait
6 + 15 = 21 minutes
If we make all trains all stops, the average journey time from Gawler to Adelaide during the day will be:
All stops + Average wait
56 + 7.5 = 63.5 minutes
But for say, Ovingham to Adelaide during the day will be:
All stops + Average wait
6 + 7.5 = 13.5 minutes
So average journey times increase slightly for Gawler, less for the other big stations. However, those passengers now have the option of getting off at more stations and the
average journey time for people at the small stations is much faster. Furthermore, making all trains all stops reduced confusion with passengers.
If we make all trains all stops and increase frequency to every five minutes, the average journey time from Gawler to Adelaide during the day is back to:
All stops + Average wait
56 + 2.5 = 58.5 minutes