The first of Queensland’s 75 trouble-prone new trains to be overhauled has been in the workshop for more than a year, blowing out the 2020 milestone for it to be back in service.

But transport bureaucrats overseeing the $335 million New Generation Rollingstock patch-up project insist the overall project to fix disability access issues will be finished as planned sometime in 2024.

The Transport Department’s website shows the first of the NGR trains was to have entered the workshop for repairs in October 2019 and would be back in service by 2020.

But a spokesman this week confirmed it was now looking at early 2021 as “minor finishing works” were needed.

He said the second and third trains were “on track to be upgraded ahead of schedule” and the overall project was on budget and on schedule, with all 75 trains to be back in service by 2024. The department did not say when in 2024 the upgraded NGR trains would be running.

A New Generation Rollingstock train.

The NGR project has been plagued by problems that triggered a Commission of Inquiry in 2018 into how they were rolled off the production line with a design that breached disability access laws.

Former Labor Deputy Premier Jackie Trad in 2017 blamed the bungle on the former Liberal National Party administration for ordering “half-price trains from India.”

But the Commission of Inquiry instead found the fault was with project managers ordering non-compliant trains and awarding the contract “on the basis of non-compliant designs”.

Inquiry head Michael Forde found in December 2018 that there was a “general acquiescence to noncompliance,” along with “lack of rigour, continual slippages and missed milestones”.

The NGR project was launched 12 years ago and spanned five elections, covering both Labor and Liberal National Party administrations.

Canadian-based train builder Bombardier was chosen in 2013 to build the trains in India, but the project was plagued by delays, including over non-compliant toilets and aisles widths. There were also teething problems after their rollout, such as malfunctioning doors.

All 75 of the trains are being rectified at Downer EDI’s Maryborough workshops as part of a 2017 election commitment by Premier Annastacia Palaszczuk.

Ms Palaszczuk, wearing a pink hard hat, promised a further $600 million work for Maryborough building 20 trains for the Cross River Rail project during an election campaign announcement at Downer’s Maryborough plant last month.

Members of the disability community inspected the first NGR train to enter the rectification program several weeks ago in Brisbane and identified only minor issues, raising questions about the length of time before it is returned to service.

“The disabled community has entered into this process transparently and any extensions or blowouts in timelines should be communicated in the same transparent manner..” Disability advocate Geoff Trappett said yesterday.

A Transport Department spokesman indicated the first stage of the upgrade project was the most cumbersome as it was then that issues were resolved before full production could start.

Transport Minister Mark Bailey said the project was on track and would ramp up next year.