I don't know how official that one was (looked like an artists impression, in pencil?).
The idea would be for minimal changes from the current JC1/Canberra design, just a 20 m lengthening (and Perhaps an enlargement of the front elevator to take 2 aircraft). Lengthening the hanger by ~20m, the vehicle deck by 20m, accommodation etc as well (additional crew space). Food and weapon bunkerage could also be enlarged and there could be additional JP-5 storage.
However, I would imagine there would be issues with a longer build, I don't imagine it would sit on Blue Marlin. Slower top speed etc. The idea would be JC1 operating costs/crewing, but closer to US LHD levels of capability (Well either greater amphibious capability or amphibious and Fix air wing, or superior pure carrier capability.
There are a number of issues in the pervious post that deserve comment:
Jumboising the LHD - possible and best done in the centre transverse section at its widest point on very fine hull forms. If the centre body of a ship is a 'regular' shape then it can be plugged anywhere along this length. The LHD design has a arc running along the curve of the bilge (look at the image on the Blue Marlin) that appears to suggests there is only one point to cut
The issue with plugging ships is the carry throught structure and catering for the additional hull stress of the added length. If you look at the three FFG7 that were extended aft this resulted in additional strengtherning along the hull.
All wasy best to build new where practical.
Revised design - Even if you build new and revise the design it is not as simple as you may think. This will have implications for the longtitudinal strength of the ship and, as noted, may impact performance. Not always in a bad way, I was associated with a company that plugged some small box boats that were short and stout and increased their speed for the same installed power as longtitudinal stablity was improved as was water flow through the prop and over the rudder.
However, in the case of the LHD this may necesitate a significant redesign as adding 20m to a 32m beam may cause some flexing. Just speculation at this stage. Noting the vessel is 230.82m long but the flight deck is only 202m then a simpler option may be to extend the flight and elvator further aft (not that the latter may be able to go too far further aft) to provide additional length without changing the hydronamic perforamce of the hull. It is worth noting that removal of the dock and associated pumps, gate and structure will free up weight, space (including hanger space if you use the lower vehicle deck) and tankage and would allow a continous structure across the stern (same strength for less weight).
Speed - I do not know what the limiting hull speed of the LHD is but given the hull form the block cooefficient is not high compared to some containerships. Moderate additional speed (not talking 30 knots but 22 to 24 may be acheivable) with more powerful gensets and higher rated pods may be an option. As an air capaable ship additional generator capcity may be required but the removal of the well structure may allow some fiddling with spaces to allow some auxillary machinery to be move to provide more space in the main machiery spaces (mucking about with exhaust routes and air intakes can really complicate your life) for bigger units. Again just speculation.
Bigger lifts - When you cur holes in strength decks this gets really interesting. Doubling the size of the fwd lift would reduce hanger area, intrude into the launch landing area and would result in a weight penalty for the structure required to reinforce the deck. You would ahve to wonder if was worth it.
Adding a ski jump to an existing ship - Doable as has been proven by the RN but not as simple as it seems. Adding quite a few hundred tonnes on the bow will impact:
- Bending mements
- Longitudinal stability (heavier by the bow, do you need to compensate with weight aft)
- Torsion forces (as it is offset)
- Transverse stability (increase in CoG and off set)
- Uplift capacity unless you increase the allow a deeper draft ......... which may impact performance
As I said all doable but not simple
