First Look - Jervis Bay Class Inshore Support Vessel

[LEUT_East]

Hello fellow Shipbucketeers,

As promised, here is the first look at the WIP of my Jervis Bay Class Inshore Support Vessel.

First of class is HMAS Jervis Bay:

Australia, Jervis Bay Class L22 HMAS Jervis Bay (1725 30-03-2012).png

Specifications to follow.

[klagldsf]

That forward Phalanx is going to get swamped in heavy seas, or even during normal operational cruising. Other than that...well, this design is so far beyond my limited amateur-tise that I honestly can't really comment on it.

[heuhen]

Hm.... You need a bit more hull in the front on those two hulls, and lest aft. because the most of the weight in the boat is laying in front of the boat center of gravity.

[Rowdy36]

I like it, and I'm looking forward to the specifications - is it kind-of a larger more capable version of the RL Jervis Bay? (and I'm glad my MRV80 drawing was helpful )

[LEUT_East]

Done a few tweaks to the outriggers to aid in the seakeeping characteristics.

Australia, Jervis Bay Class L22 HMAS Jervis Bay (1554 01-04-2012).png

I have also replaced the forecastle mounted Phalanx with an Oto Melara 76mm SR stealth mount. There are some minor detail changes as well.

Second of class L23 HMAS Shoalwater Bay is soon to follow.

[Rodondo]

Argh! Why doesn't the ADF employ you to draw these beauties for them! I really think they should!

[acelanceloet]

I have doubts for 4 things:
- would the oto 76 not be sweeped off just as easy as the phalanx? the fact that that is an dangerous position remains
- I do not know if the THALES HERAKLES can guide the (semi active) ESSM. IIRC, it has been designed to guide the (active) ASTER 15 en ASTER 30. ESSM is not mentioned in it's specs.
- what heuhen says: center of gravity. you have engines around/before midships, accomodation and systems before it, and the relatively low weight hangar and vehicle decks aft. this might cause your ship to have so much forward trim that your waterjets will be more out then in the water in all but the lowest sea states.

[LEUT_East]

- what heuhen says: center of gravity. you have engines around/before midships, accomodation and systems before it, and the relatively low weight hangar and vehicle decks aft. this might cause your ship to have so much forward trim that your waterjets will be more out then in the water in all but the lowest sea states.

That has been a concern of mine as well. My logic was that the vehicle deck would be forward of the side loading door up to just aft of the forward APU. Added to this the 4 landing craft bays (2 x port/2 x starboard) and the weight should then be balanced amidships. Then under the rear of the flightdeck I would place the mission modules, auxilliary machinery, refuelling bays (1 x port/1 x starboard), aviation fuel tanks, overload messing (ie for aircrew and embarked army personnel) and naval victualling/stores - adding significant weight aft to balance out the vessel. I am even considering moving the vehicle loading door forward of the landing craft bays so the vehicles are embarked/disembarked forward but will be stored aft. I have used Chinese trimarans as a guide for waterjet placement and I have also thought about electric propulsors instead of waterjets. She is still very much work in progress and I still have some research to do to get the design right.

- I do not know if the THALES HERAKLES can guide the (semi active) ESSM. IIRC, it has been designed to guide the (active) ASTER 15 en ASTER 30. ESSM is not mentioned in it's specs.

Yeh, I agree but again more research is required on this. I am thinking of putting a phased array in its place capable of terminal velocity tracking so I can omit the director

- would the oto 76 not be sweeped off just as easy as the phalanx? the fact that that is an dangerous position remains

I have moved the mount much higher in the superstructure and out of the "wet zone". This required some tweaking of the forecastle and forward superstructure (pics to follow soon).

[acelanceloet]

the chinese ones are a lot smaller, aren't they? those are inshore craft, lot less wave problems and all.... you'd better look at ferrys and the LCS 2 the landing craft bays are also empty space, unless of course you keep them permanently full of water (which is an bed idea, free liquid surface problems and all..) the fact is that you have to keep both the weights of an empty and an full ship in mind with a ship like this.... full it will work, empty...... that is gonna be an problem, you would have to take tons of ballast to keep the waterjets in the water. an good idea to balance out is to move the engines aft of midships, on both sides, with the cargo space and hangar between the uptakes and intakes.

ow and I forgot point 4: why mk 41 on that position, why not mk 48?

[LEUT_East]

Some changes.

Australia, Jervis Bay Class L22 HMAS Jervis Bay (2028 01-04-2012).png

Specifications are being put together currently.