Todjaeger
Potstirrer
The above is why I suspect topweight was such an issue for the RNZN's frigate configuration. The RAN first starting ANZAC-class frigates quad-packed with ESSM with the entry of HMAS Warramunga back in 2001, well before the ASMD upgrades which changed the RAN frigate's profile and required ballasting, etc.One CAMM weighs about 100 kg, so 20 would only be 2 tons.
There's also a gas generator for cold launch, but I'd be surprised if that & any other bits & pieces weigh 500kg, though.
Quad-packed CAMM has been integrated into Mk 41 & was test fired some years ago. The Swedes have bought CAMM together with ExLS, & acording to LM the host version of ExLS slots into Mk 41. That appears to have been how CAMM was fitted into Mk41.
By my calculations, the increased displacement due to quad-packing ESSM vs. eight cells loaded with a single RIM-7 Sea Sparrow is some 7,120 kg not including any extra displacement due to cannisters, etc. With the RNZN frigates having a Mk 15 Phalanx atop the hangar, they were already using up some 5,700 kg of topweight displacement so I suspect there were inadequate margins to add a further 7 tonnes topweight.
Had topweight not been such an issue, then I would think that NZ would have kept the Mk 41 VLS and just quad-packed Sea Ceptor rather than going to the expense of removing the Mk 41 VLS to install a different, smaller and lighter VLS system for Sea Ceptor. If cost was the primary driver, it would likely have cost less to just keep the VLS which was already installed and integrated.
It also might very well be/have been that the ballasting aboard the RAN frigates reduced the freeboard more than the RNZN felt was acceptable, but that would still have been a topweight issue