An expert is surprised at the extent of the LRT door issues
When passengers hold doors open for others, system at risk of shutting down
Door problems are common in a new LRT, says a professor who studies transit engineering — but they don’t usually stall the whole system in its tracks.
Doors “are historically the most problematic parts of the operation,” said Jeff Casello of the University of Waterloo. They are the only operating controls with which passengers interact.
And train builders must design doors to be “fail-safe. If there is an observation that there is something awry with the door, the doors will actually stop the operation of the train. That’s purposeful.”
But Casello said doors usually can be reset after a brief period. Sometimes this happens automatically: “You sit there for 20 seconds or 30 seconds and retest” and continue if the doors are now closed properly. “Or it could require a manual override” by the train operator.
“When I heard the situation in Ottawa I was surprised to learn that there wasn’t the capacity for the operator to manually reset the doors, and that it actually brought the system to a halt.
“The normal system would be that in the case when the system itself didn’t reset, the operator would be able to override the door delay. I was surprised to learn that that wasn’t possible. I’m not being critical of Alstom (the manufacturer) or Ottawa’s transit operator but the norm would be that it would be able to be managed, and it wouldn’t bring the system to a halt.
“They have paused the system for an extended period of time and that would be inconsistent with my expectations,” he said. “The sensitivity (of sensors) probably isn’t the problem. It’s the ability to reset.”
But he said door problems are not a surprise in a new system, even after months of testing.
“This is very difficult to test, because we don’t often test with fullcrush loads (of passengers.) And so the likelihood of someone bumping into the door or holding the door is much less until you really move into meaningful operation.”
There’s an unfortunate sideeffect, he said. With a new transit system, “there is a very small window (of time) to make a positive impression or a not-so-positive impression.
“If your first experience is one where you get delayed for 45 minutes and the doors don’t open … that’s obviously not what the transit agency wants to happen.”
His message to Ottawa commuters: “Be patient. This is not an unusual situation and it shouldn’t be a substantive or long-term fix.”
At the University of Ottawa, engineering professor Wail Gueaieb also suspects that testing failed to prepare for real-world conditions.
He used to work for a company that supplied parts to Ford, General Motors and Toyota, “and we used to run very, very rigorous tests in our systems” before delivering them. “An important part of this was repeating automated tests many thousands of times in all kinds of conditions,” he said.
“It can be tedious at times but it is very important.”
He believes the doors did not get enough testing, especially under real-life conditions where passengers push them open improperly.
“When I hear of these issues in the LRT, that is the first thing that comes to my mind — that the testing process hasn’t been done properly.” He said he has no direct knowledge of the testing, but said proper testing should ensure a system is reliable when it enters service.
The problem could be hardware or software or a combination of both, both professors said.
Alstom SA, the French company that built the train, sent a brief email refusing to discuss the issue.
OC Transpo has a pinned tweet asking people not to hold the doors open. It was getting a lot of responses Wednesday from frustrated passengers, including Allison Kerns: “I missed 4 separate trains this morning because the doors closed too quickly for everyone who wanted to get off. There was no time for people on the platform to get on. You need more trains, more buses, and for the doors to stay open longer.”
One passenger wrote: “This is most ridiculous thing I’ve ever seen. This is the first metro/subway/tram that ‘breaks’ when the doors are held open.”
And several noted that passengers without seats often cluster by the doors, reducing access to them, because they can’t reach the higher hand grips elsewhere.
A second emerging issue is the level of crowding. Transpo says the number of passengers taking buses downtown has ranged between a peak 10,000 an hour (in 2016) and 9,000 (in 2017). LRT is designed to take a maximum of 10,700 per hour — 700 more than the recent peak in 2016. That puts LRT near capacity as it enters service. tspears@postmedia.com