A fourth government ship inspector has said he cannot remember whether there was a watertight door in the aft bulkhead of the Lamma IV that might have slowed its sinking after a collision that claimed 39 lives.
The evidence from retired senior inspector Mak Yat-wai came on a day when counsel for a commission of inquiry into the tragedy, Roger Beresford, asked another witness: "Where does the buck stop?"
Mak, who approved the inclining tests designed to test the vessel's stability - conducted in 1998 and later found to be based on wrong information - said he had no recollection of seeing an opening in the bulkhead.
A naval architect earlier said in an expert report presented to the inquiry that a missing watertight door in the bulkhead had led to the flooding of three compartments, contributing to the speedy sinking of the boat after the October 1 collision with the Sea Smooth off Lamma Island.
Beresford's question came during the testimony of senior ship surveyor Leung Wai-hok yesterday. "We have had one surveyor at the beginning saying he was only required to check the hull, and the watertight door might not have been submitted [for inspection] yet," the lawyer said. "And we have had another surveyor at the end saying that he was only required to check certain things and he was not required to check the hull. So where does the buck stop?"
Leung said: "I have nothing to add on this matter."
The commission heard that Mak in 1998 approved damage-stability calculation on Lamma IV, after an 8.52-tonne ballast was installed, that carried mistakes.
The naval architect of Cheoy Lee Shipyards, which built the vessel in 1995, had mistakenly assumed there was a watertight door at the aft bulkhead, and calculated the data based on the fact that there were six compartments, instead of five, in 1996. The commission was told the length of the steering gear compartment was also wrong.
The mistakes were carried over into two subsequent calculations in 1998 and 2005.
Asked by Beresford if he agreed the compartment length was only 0.87 of a metre, Mak said: "This is not reasonable."
Told that the length on the ship drawings read 1.625 metres, he could not explain the discrepancy. "This is from computer software, and I do not understand what the convention was."
Cross-examined by Felix Pao, for Cheoy Lee, Mak said he was aware that the six compartments should be considered as five when he fed in the data to the computer.
When presented with the same discrepancy, Leung, who approved the 1996 calculations, said: "This is only basic data and it is not for me to check against this data at the final stage ... It should have been checked by my colleagues."
The hearing continues today.