Some interesting observations

[BrizCommuter]

BrizCommuter has 30 minutes up his sleeve on Friday morning, so decided to have a look at actual service frequencies through Fortitude Valley station in the am peak, between 7:54ish and 07:25ish. Average headway are between observed trains, rather than whole time period.

Platform 1/Up Sub (ex-Ferny Grove, Airport, Doomben, Shorncliffe)
2:50
2:30
5:42
5:57
4:04
2:44
2:57
3:19
Av recorded headway 3:45

Platform 2/Down Sub (ex-Gold Coast, Beenleigh, Cleveland)
(No trains for 1st 5 mins!)
2:21
2:36
3:26
5:06
2:52
2:22
4:00
2:26
Av recorded headway 3:09

Platform 3/Up Main (ex-Petrie, Caboolture, Nambour)
2:32
5:39
3:42
3:12
3:05
3:04
4:42
Av recorded headway 3:47

Platform 4 not recorded.

Some notes

• Platform 1 - It seems to be possible that trains can be realistically timetabled through platform 1 using 3 minute slots in phase 2 timetables with maybe a few gaps for delay mitigation. The current timetable has multiple huge gaps and is not making effective use of the available track capacity.
• Platform 2 - There were some large service gaps, followed by multiple services running very close together. If phase 2 can get the merges right at Park Road and South Brisbane then 20tph could be run reliably through the CBD. 23-25tph as per ICRCS would leave very little operating margin.
• Platform 3 - Services are timetabled every 3 minutes during this period, but the average recorded headway was 3:47. At least one more service should have been run through during the observation period. Problems further up the line? Can the phase 1 timetable reliably run 3 minute headways through the CBD between 7:36 and 8:24am (at Fortitude Valley)?
• The highest train loadings observed on services from the North were all on ex-Ferny Grove Line services