The Australian government in an official announcement on June 5 declared their intention to proceed with the next phase of the life extension for Collins-class submarines dubbed “Life Of Type Extension” (LOTE). The Collins-class comprising six boats represents the current submarine capability of the Royal Australian Navy.
Life extension to keep Collins operational for two more decades
Collins originally commissioned with RAN, after significant development troubles, in the late 1990s and early 2000s. Australia then pursued a successor dubbed Attack-class under its SEA 1000 program. That effort however saw cancellation in 2021. Instead Canberra is now determined to introduce nuclear powered submarines in cooperation with the USA and UK under AUKUS. Due to the resulting significant gap for a timely replacement Collins will now have to serve throughout the 2030s and possibly into the 2040s. To enable this plan, the design requires significant life extension measures keeping the boats operational exceeding 40 years of service.
In this context all six boats are to undergo a package of modernization including propulsion, weapons and sensors. However the new announcement now shelves the previous plan of integrating Tomahawk land attack cruise missiles (TLAM) and a new optronic mast produced by French supplier Safran.
Torpedo tube launched Tomahawk unfeasible
RAN intended to equip Collins with the Tomahawk missile for providing additional “strike and deterrence capability”. The phrase is ironically again used in the June 5 statement dropping the capability. Australia took this decision based on “advice from Defence, in consultation with the United States, that adding Tomahawk cruise missile capability to the Collins class submarines is not viable and does not represent value for money.” Collins would have to use the torpedo-tube launched variant of TLAM, which, as Naval News understands, has been out of production for over 12 years.
Pursuing this plan therefore therefore necessitates renewed production through a meaningful bulk order. Alternatively Australia would need to buy suitable weapons from remaining stock, if any, of the US Navy. The USN only operates three Seawolf-class SSN equipped to use TTL Tomahawk. The current status of the remaining USN stockpile of weapons remains unclear. The UK is another existing user, operating the type on Astute SSN. The Netherlands previously intended to modify its old Walrus-class SSK for use of TLAM. The Dutch Navy was furthermore planning to use the tube-launched TLAM also on their Walrus-successor dubbed Orka. Recent Dutch media reports suggest this plan is in trouble over American unwillingness to approve integration on the French-designed Orka-class. Dutch officials have dismissed related problems in response.
Modern optronics dropped from LOTE
In addition the announcement clarified that the Safran-developed optronic mast system will not be part of LOTE. Safran originally developed the Australian variant for use on the cancelled Attack-class submarines. The shifting Australian attitude on using the optronic mast for Collins was apparent already in a Senates Estimates exchange with ADF officials back in February. At the time senator Jacqui Lambie grilled Defence-officials including the Chief of Navy Vice Admiral Hammond on expenses incurred for the mast. According to the estimates hearings in February and June, Defence has already spend AU$33 millions on the optronic mast before deciding to abandon the effort integrating it in the Collins.
Other aspects of LOTE continue to be more obscure. As indicated above, the total package also includes modernisation of the diesel engines, considered the top priority for LOTE. In addition work on the electric motor, sonar and hull regeneration measures are also key aspects. The first boat to undergo LOTE is HMAS Farncomb, second of the class. Recent media reports highlighted the discovery of “unprecedented levels of corrosion” on both Farncomb and her sistership HMAS Sheean. Government officials have yet to clarify how these issues will impact the overall timeframe and scope of the life-extension for Collins going forward.