HMAS Collins (SSG 73) is the lead vessel of the six-submarine Collins class operated by the Royal Australian Navy (RAN).

Named for Vice Admiral Sir John Augustine Collins, Collins was laid down in February 1990, and was the only submarine of the class to be partially constructed by Kockums' Malmo shipyard. The boat was launched in August 1993, but was not completed until ten months later. Numerous problems with the class were exposed by the lengthy sea trials period undertaken by the boat; Collins was not commissioned into the RAN until mid-1996, eighteen months behind schedule, and the submarine was not cleared for operational deployments until 2000.

With the decommissioning of HMAS Anzac on 18 May 2024, Collins became the First Lady of the Fleet as the longest serving commissioned RAN vessel.

Construction Collins was laid down in February 1990.Jones, in The Royal Australian Navy, opp. p. 240 The two most complex sections of the first submarine were constructed by Kockums' shipyard in Malmö, Sweden,Yule & Woolner, The Collins Class Submarine Story, pp. 142–4 while the other four sections and complete assembly of the submarine occurred at Australian Submarine Corporation's facility in Port Adelaide, South Australia. It was originally planned to construct the first submarine completely overseas, but by the time the tender was awarded, it had been decided to build all six submarines in Australia; the increase in cost by not building the lead ship in the winning designer's home shipyard were believed to be offset by the additional experience provided to Australian industries.Woolner, Procuring Change, pgs. 4, 9

While the bow section of the first boat was being assembled in Sweden, multiple defects in the hull welding were discovered.Yule & Woolner, The Collins Class Submarine Story, pp. 144–6 Different reasons were given by different parties for the problems: the steel alloy used for the hull required different welding techniques to those normally used by Kockums; the Swedish navy always requested partial penetration welds for their submarines, while the RAN wanted full penetration welding but failed to make this clear; delays in delivering the steel plates to Kockums resulted in rushing the work and the resulting drop in quality. It was proposed that the section be kept by Kockums to repair the welds, but it was decided to accept the section as-is and repair the welds at ASC to minimise delays in the project.

The launch of Collins was originally planned for 1994, but was later set for August 1993.Yule & Woolner, The Collins Class Submarine Story, pp. 187–8 The submarine was launched by shiplift on 28 August 1993.‘Built in Australia’ Collins rolls out, Jane's Defence Weekly Although launched on schedule, she was not complete: the design of the submarine had not been finalised, important internal pipes and fittings had not been installed, the components of the combat system had not been delivered, and some sections of 'hull' were sheets of timber painted black so the submarine would appear complete in photographs of the launching ceremony.Yule & Woolner, The Collins Class Submarine Story, pgs. 188-9, 193 Within weeks of the launch, the boat was removed from the water, and it was not until June 1994 that she was completed.Yule & Woolner, The Collins Class Submarine Story, p. 193 Work on the other submarines in the class was delayed by the extra effort put in for Collins to meet her launching date, and by the subsequent work to complete her.Yule & Woolner, The Collins Class Submarine Story, p. 188 The submarines are covered in a skin of anechoic tiles to minimise detection by sonar: Collins was retrofitted with the tiles after the standard sonar signature of the submarine had been established, while the other five boats were covered during construction.

Collins was named for Vice Admiral Sir John Augustine Collins; famous for commanding during her Mediterranean deployment in 1940–41, and becoming the first Australian to command a naval squadron in 1944.Yule & Woolner, The Collins Class Submarine Story, p. 340

Characteristics

The Collins class is an enlarged version of the Västergötland-class submarine designed by Kockums.Woolner, Procuring Change, p. 7 At in length, with a beam of and a waterline depth of , displacing 3,051 tonnes when surfaced, and 3,353 tonnes when submerged, they are the largest conventionally powered submarines in the world.Jones, in The Royal Australian Navy, p. 244Wertheirm (ed.), Combat Fleets of the World, p. 18 The hull is constructed from high-tensile micro-alloy steel, and are covered in a skin of anechoic tiles to minimise detection by sonar.Yule & Woolner, The Collins Class Submarine Story, pp. 165–74 The depth that they can dive to is classified: most sources claim that it is over ,Wertheirm (ed.), Combat Fleets of the World, p. 19Grazebrook, RAN prepares for Collins class

The submarine is armed with six torpedo tubes, and carry a standard payload of 22 torpedoes: originally a mix of Gould Mark 48 Mod 4 torpedoes and UGM-84C Sub-Harpoon, with the Mark 48s later upgraded to the Mod 7 Common Broadband Advanced Sonar System (CBASS) version.SSK Collins Class (Type 471) Attack Submarine, naval-technology.comHeavyweight Torpedo – Mark 48, United States Navy Fact File

Each submarine is equipped with three Garden Island-Hedemora HV V18b/15Ub (VB210) 18-cylinder diesel engines, which are each connected to a 1,400 kW, 440-volt DC Jeumont-Schneider generator. The electricity generated is stored in batteries, then supplied to a single Jeumont-Schneider DC motor, which provides 7,200 shaft horsepower to a single, seven-bladed, diameter skewback propeller.Grazebrook, Collins class comes up Down Under The Collins class has a speed of when surfaced and at snorkel depth, and can reach underwater. The submarines have a range of at when surfaced, at at snorkel depth. When submerged completely, a Collins-class submarine can travel at maximum speed, or at . Each boat has an endurance of 70 days.

Sea trials

Training Assembly of the crew for Collins began in 1992.Yule & Woolner, The Collins Class Submarine Story, p. 206 Problems with the Collins trials began in mid-1992, when it was discovered that appropriate training materials and courses in the operation of the new submarine design had been poorly prepared, was inadequate, and often did not reflect the reality of operating the boats.Yule & Woolner, The Collins Class Submarine Story, pp. 206–7

Several causes were identified: the late completion of the design made preparing training materials difficult, subcontractors did not always provide detailed information on the operation of their equipment, the combat system training was based on the completed version of the software and not the partial system installed in Collins, and the training assumed that none of the systems would break down. The last problem was part of an overall attitude that the first boat would be perfect off the production line and that no breakdowns would occur, and as a result, early equipment manuals tended to be light on content, and Collins would be sent to sea with few spare parts.Yule & Woolner, The Collins Class Submarine Story, pp. 214–5

During sea trials, the submarine was often forced back to port because of equipment problems, where the Navy personnel found that ASC engineers would diagnose and repair systems using a combination of supplier data and diagnostic tools not available to the sailors.Yule & Woolner, The Collins Class Submarine Story, pp. 215 Problems with the training were compounded by an attitude from ASC that problems were always the fault of the Navy operators.Yule & Woolner, The Collins Class Submarine Story, p. 214 However, most were the result of equipment failure, and the problems caused by operator error could be attributed to poor training or a lack of training, both of which were the responsibility of ASC.

To supplement this training, several officers and sailors assigned to Collins were sent to Sweden to train with the Swedish Navy aboard the Västergötland-class submarines; the class on which the Collins-class design was based.Yule & Woolner, The Collins Class Submarine Story, p. 208

Trials Evaluation of the submarine was based on attaining a series of licenses, gradually testing the capabilities of Collins and those operating her from surface sailing to deep, unaccompanied dives.Yule & Woolner, The Collins Class Submarine Story, p. 211 The main motor was started for the first time on 8 August 1994, as part of a series of 'basin trials'.Yule & Woolner, The Collins Class Submarine Story, p. 212 Collins officially commenced sea trials at when she departed the ASC wharf at 10:00 on 31 October 1994. By the time the submarine had exited Port Adelaide, two of the three diesel generators had broken down. The submarine submerged for the first time on 9 November, remaining underwater for twelve hours.

The submarine was removed from the water at the end of 1994 to allow ASC to further complete the fitting out of the boat and perform repairs to the hull. Although sea trials resumed in early 1995, Collins did not dive again until 9 June, when it was decided that the status of the combat system drop was sufficient to allow further underwater tests of the submarine.Yule & Woolner, The Collins Class Submarine Story, p. 213 The tests went without difficulty until the next day, when the anchor cable snapped in poor weather, forcing Collins to return to port. When approaching the ASC wharf, a programming problem with the propulsion switchboard caused the main motor to cut out. Collins drifted into the wharf, hitting the construction facility's shiplift at . The backup motor then belatedly engaged, causing the submarine to collide with , the ship assigned to assist in the submarine's sea trials. Repairs to the sonar dome cost A$250,000.

Deep diving tests were delayed until the acquisition of the submarine rescue vessel Remora in December 1995. Collins performed her first deep dive on 19 January 1996 without any problems. However, during a later deep dive trial, the propeller shaft seal began to leak excessively.Yule & Woolner, The Collins Class Submarine Story, p. 233 Although designed to leak at an hour, the seal had previously shown itself to be faulty, with an hourly leak rate in the hundreds of litres. On this occasion, the water pressure meant the flow rate was significantly greater, to the point where the aft bilge pump was barely keeping up. When the senior engineer entered the compartment, he found personnel trying to stem the flow, including one sailor who was underneath the shaft, attempting to tighten the seal manually. The engineer instructed the commander to take the submarine to the surface as quickly as possible, but keep the boat level—had the engineer instead informed the commander that the submarine was flooding, Collins would have blown all ballast and driven for the surface at a steep angle, likely drowning the sailor under the shaft. Collins reached the surface without further incident. Modified seals were fitted to all submarines to bring the leak back to the accepted rate. It was later calculated that the submarine was taking on water at over a minute.