Ballast made Lamma IV 'sink like Titanic'
Naval architect also says life vests on boat were tied up in plastic bags like 'somebody's lunch'
Ballast that added 30 per cent to the weight of the Lamma IV made the vessel "sink like the Titanic" after its collision with the ferry Sea Smooth, an inquiry into the National Day sea tragedy heard yesterday.
Naval architect Dr Neville Armstrong also criticised storage of the boat's life jackets, which he said resembled "somebody's lunch". Armstrong, a commission-appointed expert, said the 8.25 tonnes of lead and seven tonnes of unspecified material were installed in the stern of the Lamma IV in 1998 to stabilise it.
But it substantially reduced the efficiency of the Hongkong Electric boat's sub-division - the segregation of hull compartments that enabled the vessel to remain afloat when damaged.
"It was not recognised at the time that the watertight subdivision had been compromised by the addition of weight," Armstrong said.
When the boat was built in 1995, it had "excellent" sub-division that would have allowed it to remain afloat when any two compartments were flooded.
But when it was damaged in the collision off Lamma on October 1 last year, it sank very much like the Titanic did in 1912 - upright by the stern without tipping to either side. Armstrong said earlier that the need for watertight partitions in ships was first recognised after the sinking of the Titanic that led to 1,502 deaths.