The commission's investigation will focus on the causes and circumstances of the incident and the Maritime NZ investigation will focus on whether the rules were followed correctly.
Maritime New Zealand's deputy director of safety response systems, Nigel Clifford, said the vessel would be able to continue on to China, if it is "safe to sail without repairs".
"If the vessel requires repairs a repair plan will be established by the owners. Authorities would overview any such proposals."
Commission spokesman Simon Pleasants said a team of three investigators left Wellington for Tauranga mid-morning.
He was not sure whether they would board the ship this afternoon as the interviews could take some time and, for safety reasons, they would not want to be disembarking at night.
The log carrier that lost power at the entrance to Port of Tauranga this morning is now safely anchored in deep water outside Tauranga Harbour. The final update from @Portoftauranga can be found here: https://t.co/kT4TwHuNOm
— Maritime New Zealand (Nō te rere moana Aotearoa) (@MaritimeNZ) July 5, 2020
A Port of Tauranga spokeswoman said the ship was being piloted out of the harbour "as normal" when the engine failure happened.
"A second pilot was transferred on to the vessel several hours after ... to relieve/assist the first pilot." Both pilots had since been taken off the ship.
Tug boats were also requested to help the vessel.
"Our marine teams did an amazing job in keeping the stricken vessel steady and then towing it to safety."
"The wind and swell was challenging for all vessels involved but the conditions eased throughout the morning," she said.
