Flat-Top Bommie is a Silverswift site on Norman Reef, and Silverseries describes it as a large coral outcrop separated from the main reef by a deep channel, with swim-throughs and coral canyons, depths of 3-18 m and visibility of 10-20 m. The operator notes that it suits all skill levels and offers undulating reefscapes with a diverse underwater landscape. The name describes the outcrop's top, a broad, flat surface of coral a few metres below the surface that makes an excellent place for snorkellers and for a long safety stop.

From that top, the sides of the bommie drop into deeper water, cut by canyons and pierced by swim-throughs. The channel separating it from the main reef adds interest: channels concentrate water flow and fish, so schools of fusiliers and snapper, trevally and reef sharks are often seen in and around it. The coral canyons are sheltered corridors where hard and soft corals grow densely, with anemonefish, damsels, parrotfish and angelfish, and the swim-throughs host cardinalfish, soldierfish and sometimes sleeping whitetip sharks.

Turtles, giant clams and moray eels are common on Norman. Depths are moderate and the layout, circling a single outcrop, is easy to navigate, which makes it a good site for Open Water divers and for divers who want to practise buoyancy in swim-throughs. The channel should be crossed only when the current is slack, following the guide's lead.

It is a pleasant contrast to the walls and bays elsewhere on Norman, and is also a good site for a relaxed final dive of the day.

Boat access only. Cairns day boats leave from the Reef Fleet Terminal (1 Spence Street) and the neighbouring Marlin Marina on the city waterfront, with check-in between about 7:00 and 8:00 am; most operators run transfers from city and northern-beaches accommodation, and there is paid parking near the terminal. The run of about 58 km out through Trinity Inlet and across the lagoon to Norman Reef takes around 82 minutes on a fast catamaran and noticeably longer on slower dive boats or into a south-easterly chop.

Flat-Top Bommie is a Silverswift site; Cairns Dive Adventures lists it among Norman sites. Enter from the stern platform.

The prevailing south-east trade winds (typically 15-25 knots from April to September) are what limit Cairns outer-reef diving: above about 25 knots trips may be cancelled, and exposed eastern moorings are used only in light winds. Summer northerlies are gentler but make north-facing moorings choppy. Box jellyfish and Irukandji are present from about November to May (stinger suits on every dive), and the cyclone season runs November to April, when a system in the Coral Sea can close the reef for days.

Visibility drops after heavy rain and strong winds; spring is usually calmest and clearest. Most Norman moorings lie on its protected western side. The channel between the bommie and the main reef can carry current on a running tide; the outcrop's top is shallow enough to feel surge in strong winds.

Descend beside the bommie, circle it at 12-18 m, cross into the channel only if the current is slack, then work through the swim-throughs and coral canyons on the outcrop, rising gradually to its flat top at 3-5 m for the safety stop.

Silverswift – occasional Norman Reef day trips; Reef Experience and other Norman operators occasionally; Norman is also worked by Divers Den (Ocean Quest liveaboard), Reef Experience, Aqua Quest, Down Under Cruise & Dive, Reef Encounter and Passions of Paradise; the mooring used on any day is chosen by the skipper according to wind, tide and other boats