Keep in mind that the RAN has released a factsheet for the
Hunter-class FFG which does address some of these questions, and others have also likely been addressed by the RAN releasing CG renderings for the Type 26 for Australia. I also noted that someone else linked to the Factsheet again as well. Those who have not seen it, take a look as it is well worth considering.
With respect to seeing the Sea Ceptor in RAN service... while I do not consider it out of the question, I also do not consider it very likely. Both the current Sea Ceptor and ESSM (block I) are short to medium-ranged SAM systems, albeit currently at opposite ends of what might be considered the short to medium-ranged spectrum, with est. ranges for Sea Ceptor being ~25 km vs. ~50 km for ESSM. Assuming spiral development goes well for both missile families, their future capabilities in a number of areas should end up getting much closer to each other. Examples being the CAMM-ER version (CAMM being the base for current Sea Ceptor missiles) having a range projected out to ~45 km, and ESSM block II having a dual-mode seeker which can use an illuminator like the current ESSM, or an active radar homing seeker like is currently found in the CAMM/Sea Ceptor missiles amongst others.
From my POV, the Sea Ceptor currently has a couple of capability advantages over the ESSM, but these 'advantages' are fairly narrow and specific in scope. Specifically, they are the fact that a launching ship or vessel does not require an illuminator to guide the missile since it uses an active radar homing seeker, and that Sea Ceptor is a cold-launch (as opposed to hot launch like ESSM) missile, so a smaller VLS which does not necessarily need to be a permanent fixture aboard a vessel could be used.
Given that at present and for the foreseeable future all RAN frigates and destroyers will have permanently fitted VLS cells and radar illuminators, bringing the Sea Ceptor missile into RAN service would not provide such vessels with any particular capability boost, since such vessels can (or will be) able to utilize the ESSM which approximately twice the max range.
The areas where Sea Ceptor might (emphasis MIGHT) provide a capability boost within the RAN, would be if Sea Ceptor could be fitted aboard support vessels and minor warships which lack the space/weight to install either/both a radar illuminator and/or an appropriate VLS like Mk 41, Mk 48 or Mk 56. IMO it would be in these vessels which currently lack a missile for self-defence purposes that adding Sea Ceptor to the RAN inventory would make the most sense. I tend to agree with Alexsa though, in that if the RAN were to add another air defence missile to the inventory which was not a part of an existing missile family, it would most likely be the RIM-116 Rolling Airframe Missile usually referred to as RAM.
An area I tend to agree with others on though is the though that it would have been better if both the planned CIWS and small calibre guns to be fitted aboard the Hunter-class FFG were the 35 mm Rheinmetall Oerlikon Millennium Gun or Rheinmetall GDM-008, or failing that, the small calibre guns to be fitted be the same as will be fitted aboard the upcoming SEA 1180 vessels. I acknowledge that lacking the specific details about the small calibre guns selected for both vessels, it is possible that the desired mounting locations aboard the two classes might not have permitted the required space and weight for the mountings, but I do feel that some degree of rationalization needs to be done with regards to small calibre guns across the RAN fleet.
At present or in the expected future the RAN expects to operate the following small calibre guns/CIWS;
- 25 mm M242 Bushmaster gun in a Rafael Typhoon mounting
- 20 mm Vulcan Phalanx Mk 15 CIWS
- 30 mm/75 Oerlikon KCB gun in an MSI DS 30B mounting
- 30 mm gun and mounting for the upcoming Hunter-class FFG
- 40 mm gun and mounting for the upcoming SEA 1180 vessels
As it stands now, that is at least four different planned sizes for ammunition (depending on whether the the 30 mm ammunition for the
Hunter-class FFG is the same as the 30 mm ammunition for the
Huon-class MHC) and a minimum of at least three different types of gun mountings and perhaps as many as five. What I would like to start seeing is both a bit more standardization across the fleet to permit operating a 'pool' of small calibre guns to ease logistical, support and training, as well as selecting small calibre guns that are suitable for engaging both fast surface craft and inbound sub/supersonic AShM at useful ranges.
