Passengers on Australia's busiest railway system will be forced to endure even more delays in a bid to address the cascade of failures that brought the network to its knees.

More than one million people were affected when Sydney's rail system ground to a halt after an overhead wire fell onto the roof of a train in May, trapping 300 passengers.

But many aspects of the situation were preventable, an independent review of the incident released on Tuesday found.

The wiring issue had been detected in 2020 but was not followed up.

Sydney Trains' maintenance regime, incident management and communications also all failed during the network shutdown that affected nearly 1300 trains.

Passengers on the train hit by a live wire were trapped for hours with little information about how long their o

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