The group that built Ottawa's Confederation Line didn't do a great job meshing Ottawa's new light rail trains with the computer system that controls them, a public inquiry has heard.

That lack of integration could even have led to the door problems riders experienced after the train system launched, one witness suggested on Monday at the commission investigating breakdowns on Ottawa's LRT.

Alstom manufactured the trains for Ottawa's LRT, while Thales Canada Inc. provided the computerized signalling system that controls braking and propulsion, doors, sensors along the tracks and more.

It was up to Rideau Transit Group's construction arm, OLRT Constructors, to do the critical job of merging the two companies' systems. The Confederation Line was the first time that a Thales communications-based train control system was being integrated with a low-floor light rail vehicle, commission lawyers pointed out. 

At the public hearings into the breakdowns on Ottawa's light rail system, however, Thales project manager Michael Burns testified that he tried to draw the train builder's attention early on to how his company and Alstom were having to sort out issues in silos rather than collaboratively. 

"They had challenges in fulfilling that role," he said of OLRT Constructors.

The commission investigating Ottawa's light rail system heard a similar conclusion last Friday from Rupert Holloway, a SNC-Lavalin vice-president and civil engineer who took on oversight of building the train system at OLRT Constructors from May 2018 to May 2019. 

He testified that Ottawa's train system involves thousands of complicated digital devices, and integrating the Confederation Line's systems was "crucial."

Holloway gave the example of how several systems would need to work together if there were a fire on a train in the tunnel. The train's computers would need to detect the fire and tell the control room at Belfast Road, fresh air would need to flow to riders as they evacuated, and elevators would need to turn off to prevent other riders from descending to the tunnel. 

In hindsight, Holloway said RTG's construction arm spent a lot of time focusing on building the tunnel — "a world-class piece of civil engineering" — but lost focus when it came to "the integration challenge."

"We certainly failed in regards of tackling that challenge as effectively as we could have done," Holloway told the commission.

Ottawa's LRT even received a bad grade six months before the original date in 2018 when the system was to be handed over to the City of Ottawa. 

OLRT Constructors had hired consultant SEMP Ltd. to do a "health check" on whether Ottawa's system was on track to be up-and-running and safe. 

"The level of system engineering on the project to date is considered to be substantially below the minimum acceptable level for a project of this size and complexity," the consultant summarized in November 2017.

"This was a real catalytic moment for us," Holloway said. OLRT Constructors then spent more than $20 million to fly in experts from the United Kingdom to help fix the gaps, he said.

Burns described a couple of instances in which Alstom had made changes to the way the trains would behave, unbeknownst to Thales.

During pre-launch testing, he said Thales discovered Alstom had changed software so that a train would stop if the emergency brake was applied too many times, for safety reasons. Meanwhile, Thales had its own test for the emergency brakes.

Then, after residents began riding the train in 2019, Burns said there was an instance when a woman was caught when a train door closed prematurely.

Malfunctioning doors continue to cause headaches for LRT riders

Burns explained Thales would have expected the door to re-open if something blocked it from closing. After investigating, it found Alstom had assigned a different command to that signal. Thales then had to modify the software to prevent that door issue.

The inquiry also heard that Thales has still not completed its work on the first stage of the Confederation Line. Under the contract, Thales was supposed to install its control system at the the maintenance and storage facility on Belfast Road, but hasn't finished.

Burns said the non-automated system in the rail yard slows down the launch of LRT system in the mornings. 

The issue of integrating various systems is expected to be discussed further Tuesday morning, when Alstom's Lowell Goudge is scheduled to testify. Goudge oversaw the train system integration and was the safety certifier for Alstom.

In the afternoon, the commission will hear from Jacques Bergeron, who was responsible for integrating the Thales and Alstom systems from 2014 to 2018.

Kate Porter covers municipal affairs for CBC Ottawa. Over the past two decades, she has also produced in-depth reports for radio, web and TV, regularly presented the radio news, and covered the arts beat.

With files from Joanne Chianello

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