Shipwrecks | Australian Diving Instruction

Shipwrecks


Dive Site Depth Certification Level
J Class Submarines    

When they were built in 1917, the J Class Submarines were the fastest in the world. They boasted a surface speed of 19 knots, and a submerged speed of 10 knots. They were 85m long, with a displacement of 1260 tons, and carried a crew of 44. Seven vessels were built. The J6 was lost during the war.
The remaining 6 submarines were a gift from the British Government to the Royal Australian Navy in 1919. However due to their high operating costs, and subsequent budget cuts, they saw little service. In 1924 four vessels, designated as JI, J2, J4, and J5 were sold to a salvage company which stripped them of valuable fittings. The submarines were then scuttled outside the Heads in 1926.
Some confusion exists among different organisations as to the naming of the submarines. We have referred to them by the names they are commonly known. A dive on any of the four scuttled submarines is both challenging and rewarding. They play host to a huge variety of marine life, and are sufficiently large to require more than one visit if the diver is to fully explore them. Divers should approach them with caution, however, owing to their depth.
Penetration inside these vessels should only be attempted by experienced and competent buddy pairs, who are both properly equipped for this type of diving. The submarines offer spectacular diving in good conditions, and many interstate divers visit our region specifically to dive them. For competent and experienced divers, they are highly recommended.

Broken Submarine 39m Deep (4)

The Broken Sub is probably the most infrequently dived of the four. It is the deepest, and it is also the closest to the Heads. It can therefore be uncomfortably close to the path taken by ships entering and leaving Port Phillip Bay. Boat operators must be aware of the shipping traffic during the dive period.
During the Broken Sub's scuttling, explosive charges caused the vessel to break in two sections. The break occurs just behind the conning tower, which tilts at a 45 degree angle. The wreck is in 39m and is surrounded by many schools of fish. These along with the extensive marine growth covering the hull, make this an interesting dive for photographers as well as wreck enthusiasts.
Being such a deep dive, we recommend that divers spend the last few minutes of their limited bottom time at a slightly shallower depth around the conning tower before beginning the final ascent. This area is usually inhabited by large numbers of fish, so there is plenty to look at before returning to the surface.
The Broken Sub is a marvellous venue for the experienced diver. Obviously more than one dive is required to fully explore it. With good visibility it is an outstanding dive.
Hazards and Precautions
The 39m depth calls for experience and training, correct equipment and very careful planning. Begin your ascent with plenty of air remaining for the inevitable decompression stops. Even at this depth surge can be a problem, especially when penetrating inside the wreck. If surge is present remain on the outside.
Penetration into the wreck is possible, at the point where the ship has been broken, but the need for extreme caution cannot be overemphasised. In addition to the normal dangers involved in penetration diving at this depth, the Broken Submarine has the additional hazard of extensive jagged and twisted metal around the break.
Once inside the wreck, it can become very dark, so good torches are essential. Care must be taken to avoid stirring up silt on the bottom, thus further reducing visibility.
One of the web developer's favourite dives!

Intact (36m) Submarine 36m Deep (4)

The 36m Sub was probably the first of the J Class submarines to be regularly dived. It lies in 36m and has been referred to as the Yellow Submarine, a reference to the yellow zoanthids that decorate a large portion of the hull. The submarine sits upright on a sandy bottom, and is virtually intact. An interesting dive can be had swimming along the outside, due to the proliferation of marine growth, and the numerous fish present.Penetration inside the wreck is possible at several points, where large plates were removed from the hull prior to scuttling. However , caution must always be exercised, and octopus regulators, good torches and a reliable buddy are all obvious pre-requisites. While swimming through the interior of these submarines, one cannot help admiring the courage of the forty-four crewmen, who lived in such confined quarters for extended periods. Due to the limited bottom time at 36m, this submarine cannot be fully explored in the dive. However it represents an exciting and challenging location to which the experienced diver will want to return , time and time again.

26m Sub 26m Advanced Open Water (3)

Scuttled in the 1920s, this submarine was rediscovered by divers in 1982. The Melbourne Bottom Scratchers Dive Club has placed a plaque at the conning tower base commemorating their find.
Known as the 26m, 27m and 90 foot sub, the wreck lies with its bow pointing out to sea. During its scuttling the bow section broke off, exposing the forward torpedoes tubes and bow modifications. Depths of up to 30m can be gained around and under the broken bow section.
As with the other Subs, the 26m sub is host to a variety of plant and animal life. Good conditions for photography are often found near the conning tower, which is usually surrounded by many fish. For the experienced diver penetration of the wreck is possible via several large openings in the hull. Such penetration should not be taken lightly, as being shallower than the other subs, this wreck is particularly susceptible to surge. Unwary divers can be literally sucked in and catapulted through the wreck's interior. However, the surge prevents any silting, and under suitable conditions this makes for one of Melbourne's top dives.

New Deep Submarine 38m Deep (4)

This is the most recently discovered of the four submarines scuttled outside Port Phillip Heads. While it makes for an exhilarating dive, it should only be attempted by experienced and properly trained divers. The vessel sits upright on a sandy bottom in 38m, with a slight list to port. Its hull is covered by a variety of marine growth, including sea tulips, soft corals and zoanthids. Its stern faces seaward, and the stabilising fins and propeller shaft are clearly visible.
Near the bow, a depression in the sea floor, makes it possible for the diver to swim under the hull and emerge on the other side. The torpedo tubes are also visible at the bow.
Hazards and Precautions
The 38m depth calls for experience and training, correct equipment and very careful planning. Begin your ascent with plenty of air remaining for the inevitable decompression stops. Even at this depth surge can be a problem, especially when penetrating inside the wreck. If surge is present remain on the outside.
Penetration into the wreck is possible, but extreme care must be taken. A cave diving reel is essential if penetration is attempted. Once inside the wreck, it can become very dark, so good torches are essential. Care must be taken to avoid stirring up silt on the bottom, thus further reducing visibility.