The Marina Bay floating platform was awash in red and white yesterday, as the last public rehearsal for the nation's biggest bash kicked off amid tighter security measures.
Speaker of Parliament Halimah Yacob observed the parade as reviewing officer, reprising a role she has played at every National Day Parade (NDP) preview since 2013.
The Speaker of Parliament and Defence Minister traditionally take on the role of reviewing officer during NDP previews, to inspect the military parade.
President Tony Tan Keng Yam will inspect the military parade at the Aug 9 NDP.
The security measures yesterday were tighter than those taken at the first preview on July 22. Spectators had their bags checked and walked through metal detectors before entering the floating platform.
But the crowd was rewarded for their patience with a visual feast at yesterday's preview. This included a display of Singapore's military might on land, air and sea.
The Sunday Times also went behind the scenes for a look at the underwater security sweeps performed by naval divers.
A team of 10 divers from the elite Naval Diving Unit (NDU) scoped out the waters surrounding the platform ahead of the preview to ensure that there were no suspicious objects in the water.
Underwater visibility typically does not go beyond an outstretched arm, but the divers were equipped with devices that use sonar to track changes to the sea floor.
Captain (NS) Marcus Teo, 33, an operationally ready serviceman who is part of the NDU team, said: "While it is not part of the main show, NDU operations in NDP 2017 are significant and relevant, as we ensure that waters surrounding the platform are safe."