Shipbucket

That was the general idea Tobius, land one side launch the other. Separation of duties. Which would cure the landing/launching problems with CV's through to the angled decks arrive. Deck flex/cracking will certainly be the biggest problem, and if this had been feasible I am sure somebody would have tried it before now. I have tried to think of as many of the problems with 'joining' the hulls and essentially came up with 3 layers. Flight deck join, hangar join, and what I call stabiliser join below water. Also have the bridge structure overlap the hulls to create another join point.

Hi K,

A bit of a late thought ... if you're going for structural stability, rather than having the underwater join go straight across, forming an almost parallelogram, why not secure the bottom of one hull to the point where the hangar structure meets the hull on the other side? This'll form a series of triangles (you may have to offset the struts to get them to clear each other) and should therefore be stronger, no? Presumably, you could also build some mounting points out from the bridge structure, which would be one of the stronger parts of the frame, I think?

Regards,
Ad

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Then get rid of the island (wind baffle and collision hazard) and use a navigation bridge about 1/3 back from the prow to PORT.

Also be prepared to lose that carrier when she's torpedoed. You can't counterflood a catamaran to remove a list, nor can you correct for wave roll in yaw and you sure don't want to launch crosswind on that broad deck.

How do you cross feed from port trap to starboard cat shot? On the flight deck or underneath it? Underneath means you don't foul traps or takeoff runs. Do you know what an aircraft carrier deck crew means by aircraft roller skating or a bolter?

A bolter is a trap that fails to catch the wire and that means the lander plows into planes parked forward. KABOOM.

Roller skating is when an aircraft being moved by men or a tractor breaks loose from grip and rolls away from the plane handlers. Since catamaran hulls pitch sideways as well as back and forth, that roller skating plane will not only roll but SKID into parked planes. Again with the KABOOM.

These things/problems are possibly why nobody ever built catamaran carriers.

But that sure is a beautiful concept as drawn. If you can make it work. It solves a host of current problems, like how to build hulls without side sponsons and deck overhang. This tends to make current angled flight deck carriers topheavy and turn turtle when they sink, if you design them wrong on the hulls like the Russians and apparently the British do.

I still like it a lot as a drawing and assuming you can cross feed and handle the deck fouling problems I think it is a dandy solution for the dockyard problem you described. It actually would make sense.

Were one to actually try to build something like a catamaran carrier, one would surely not expect the hulls to be symmetrical as you draw them. You could move all shafts inboard to hopefully prevent PoW-style torpedo damage to shaft alleys, and obviously there is no need whatsoever for bilge keels.

What about lines of thrust?

Hi Tobius,

Can you help with some bits of your post that I'm not understanding?
I'd thought you'd flood voids on the other hull. Is this impossible or unworkable on a catamaran?
I'd thought K showed the under-flight-deck hangar? Presumably this would be used for transfer of aircraft? With regards the bolter, surely this is why the crash barrier is present? Or am I misunderstanding and we're referring to a returning plane coming down onto the wrong hull and ploughing into the deck park aircraft there? Regards aircraft sliding to the side, perhaps a similar sort of crash barrier running longitudinally (not stressed to the same sort of strength, of course, as it's hopefully stopping aircraft at a substantially slower speed than those failing to land correctly) would do the trick there - you wouldn't want it to be the sort of thing that would impede transferring aircraft across the flight deck if necessary in an emergency, so I suspect a permanent barrier would be detrimental.

Regards,
Adam

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I've seen a couple of naval disasters involving catamaran ferries (the closest thing to what is illustrated above.)

It's possible to counter-flood, but you have to be quick. The problem is that you have two much smaller float bubbles and too much top weight. The cant action comes quicker and you have to calculate the imaginary incline line between the two float bubbles. It could be a quadratic rather than a linear progression as a problem.
His illustration did not show me clearly that he had allowed enough turn room or wide enough tunneling to cross the plane, I would have preferred continuous width open bay hangers (more garage space) instead of the illustrated British pattern box integrated into the hull frame. One explosion in that box and the carrier hull is swanged out of frame and you might as well write her off as a total loss.

1. You don't ever stop a bolter if you can avoid it... EVER. You want him to touch and go through a clear run across the clear deck path and back into the air for another go around if he's lucky or into the drink if he's not. The carrier comes first. Same for a roller skater. Steer over the side if it can't be stopped. Curbs on a flight deck are impractical for the very good reason you mentioned.

2. The Japanese (and now apparently the British will try with the Queen Elizabeths) tried to cross feed aircraft under the flight deck. A bomb into the hanger full of explosives and fuel and loaded planes=loss of carrier. You want explosions and fires outside the hanger, not inside it. Cross-feed on the flight deck, fuel on the flight deck, arm on the flight deck, move on the flight deck so that the explosions are outside the armor and the hull, not inside.

3. The flight deck should be as clear of wind breaks and physical obstructions as possible. The carrier operating tempo and its defense depend on the speediness of how fast it can launch and recover aircraft. There are three ways to do this currently, one called CATOBAR (catapult assisted take off back arrested recovery) and RTOBAR (rolling [ski jump] take off barrier arrested recovery) and vertical take off arrested or vertical landing. All of them require unimpeded and open recovery runs with vertical landing being the most dangerous on a cluttered deck because of the downdraft and downwash. Vertical landings are uniquely dangerous in that there is a sideways slip component as the helicopter or the jump-jet tries to slip into its assigned landing spot on a moving ship. That is why many vertical landers (helicopters) use a cable winch recovery assist to haul down onto their deck spots. Jump-jets can't do that, which is why you don't see jump jets operate off the back of frigates.

Anything that clutters a take off/trap run, even if it is a man standing in the wrong place at the wrong time is a giant error in judgment that leads to at best a delay in the operating tempo or to assorted disasters like plane on plane collisions or roller-skating or a crashed bolter or just a warmed up plane sucking that man into its engine (or setting him or something else) on fire. All of this has happened. The result is that there are rather firm and hard rules for how you design (CATOBAR) aircraft carriers. If you look at the French Charles de Gaulle or an American Nimitz, those rules are very plain to see.

The heck of it, is that most of the rules were invented by the British, who seemed to have ignored every one of them in their current aircraft carrier designs.

Regards,

Tobius

Tobius, while I have used a drawing of Illustrious as the base unit for the cat-a-carrier, I have not carried over the armour schemes. I figured that would be far too much weight at that level. The main armoured deck is at the Hangar floor level (main deck of the ship).

There is not much I can do about battle damage, except to avoid as much of it as possible. Unfortunately the early carriers of the British 1939-42 and the US in 1942 took a lot of damage. So I would fully expect to lose the Condor probably in 1940-41 to a U-Boat in the North Atlantic. While it could operate in the Med its chances of survival would go down a lot.

I have put a few aircraft aboard to show the sizes of the areas with a few aircraft in them.



Ideally I would like to have deck edge lifts/elevators to clear the take-off and landing areas. Of course the best place for those would be in the join area, which I think would weaken the join structure a bit much.

Good points.

You should look at the Essexes or the Wasp as to how to handle deck edge lifts and an open hanger architecture. Don't be afraid of it. Those four deck edge lifts, one placed at each hull quarter would (and did) serve loading points and ventilation alleys.

I'm confused as to why you have some of your planes oriented the wrong way. Is there a reason why you want them pointed backwards on the trap run and your catapults??

Sorry all the aircraft aboard are of Canard design.