Every 90 seconds isn't unusual for a modern system. Even the existing lines with the old signalling system can easily sustain every 140 seconds. Didn't they achieve 31 trains an hour through Bloor with their gap trains stored at Davisville - which is the bottleneck - pre-Covid.
The 90 seconds is achievable yes. I just mean it's a number given by on paper crush loads and very tight headways. It's also higher than Line 1 which runs trains 33% longer and a 0.2m wider at a still quite respectable design limit of 128 seconds. It's also a fair bit higher than the theoretical max capacity of the Expo line running 5 car Mark V trains at 98 seconds.
It has nothing to do with the length or width of the car; it has everything to do with the door spacing and size. And what the percent/volume of passenger changeover is.
How does it not have anything to do with the length & width of the car? Assuming equal number of doors & equal volume of people passing through them, and equal % passenger changeover, if the total number of people on the train is different, how would that not affect things?
In a modern system built from the ground-up for it? It can happen, but it's uncommon enough that I wouldn't call it "not unusual".
Only on one line that has had massive investments to the track configuration, power and signals - the Victoria Line. All the rest of the deep-tube and sub-surface lines are running far less frequently than that, with upgrades scheduled to try and get them to 120 second headways.
Vancouver has only run that kind of headway for very short spurts, such as after special events. The current headways at rush hour are more like every 135 seconds on the joint section of the Expo Line.
Are these doors big enough (the absolute maximum possible size (Ultra Pro Max™) vs. that of the T1)? They might as well do this then.
Fair enough - with can be an issue. But if there's a 4-car train or 6-car train with peak capacity, and a 50% change-over, then it's not going to make a difference. The doors are the bottleneck, and the egress time doesn't change.
I've waited a lot longer than that for the Canada Line after special events. However that's probably a different issue.
Pre-COVID, they were very close. That's why they're currently undergoing the whole ordeal of having purchased a brand new train fleet that is longer than any of the existing configurations - and all of the resultant changes elsewhere through their system to handle them.
