Could IJN Aviation Battleships Have Worked

[dy031101]

After the disaster at Midway, the Japanese were desperate to in some way make good of the loss suffered by their carrier forces.

Kongo class fast battleships were the only ones that could keep up with (and therefore escort) their surviving fleet carriers, and Nagato class and Yamato class were most definitely to be committed to "the decisive battle" that the IJN were still waiting for due to their main guns.  That left Ise class and Fuso class BBs to be considered.

As a full carrier conversion would have taken too much time, a plan was selected to give them a much increased capacity for seaplanes.  Since Ise class, unlike Fuso class, has two aft turrets on each ship that couldn't be upgraded with increased elevation (which TECHNICALLY made them less valuable as gun boats than Fuso class), Ise and Hyuga were selected for conversion.

Then came another problem- there weren't enough seaplanes to go around.



But look at the bewildering array of aircraft they came up with.  For every requirement, they built a totally new type of aircraft, often utilizing totally new components such as engines and armaments (for example, the USN use naval aircraft or adaptations of Army aircraft for shore-based units, while the IJN ran dedicated projects for land-based aircraft development).  That's not to mention that IJAAF and IJNAF had seemingly totally seperate logistic chains, with their own seperate projects doing the same thing (such as liscence-building DB-601)...... they even developed their own ordnances, which despite being of the same class and doing the same thing share no commonality at all.



So what if they instead consolidated the number of types in use down to a minimum, not developing a totally new aircraft when modifications of existing aircraft types can do?  What if they standardize as much as possible (perhaps even with the IJAAF a little)?  Would they then have had enough resource to field enough floatplanes to make the two battleships more worthwhile post-conversion?

[Son of Damian]

If the conversions had been completed as originally designed, and would allow to actually take off from the back of the ship*, then maybe.

*Remember the USN looked at converting the Iowa class battleships in a similar fashion. This entailed removing the rear turret, adding a hangar, and a flight deck with two ski jumps for harriers protruding forward along the sides of the ship.

If the Japanese had done something similar to Hyuga, Ise, and hadn't been soo squeemish about halving Fuso's and Yamashiro's main armament then they could have been more successful than they were.

But the vortexs created by the bridge would have precluded the aircraft returning to the Battle-Carrier so they would have to land on a friendly carrier. This isn't a bad idea if you think about it; have the aircraft placed on the Battle-Carrier while in port, launch them along with the carriers strike packages, and return to land on the carriers as "replacements" for lost aircraft.

You would really have to go with normal carrier based aircraft because of the poor performance of float planes in the face of carrier aircraft.

Japan's Battleship-Carriers

[dy031101]

If the conversions had been completed as originally designed, and would allow to actually take off from the back of the ship*, then maybe.

The idea was to have the floatplanes catapulted off the flight deck- there was one catapult rail on each side.

But the vortexs created by the bridge would have precluded the aircraft returning to the Battle-Carrier so they would have to land on a friendly carrier.

Seaplanes will have to be recovered from the sea anyway.

You would really have to go with normal carrier based aircraft because of the poor performance of float planes in the face of carrier aircraft.

I'd imagine it'd have been just an interim measure anyway- maybe they could've come up with a successor of Kyofu that could hold its own for a while, but I think we can all agree that conventional carrier-based aircraft development will overtake it in the long run.



Incidentally, the USN and Kriegsmarine did run some studies on flight deck cruisers operating conventional carrier-based aircraft.

[elmayerle]

So what if they instead consolidated the number of types in use down to a minimum, not developing a totally new aircraft when modifications of existing aircraft types can do?  What if they standardize as much as possible (perhaps even with the IJAAF a little)?  Would they then have had enough resource to field enough floatplanes to make the two battleships more worthwhile post-conversion?

Now that bit's really whiffy, expecting bureaucrats to give up their empires simply because something as important as the country's survival is at stake.  Can you tell I'm underwhelmed by government bureaucracies, at every level?

[jcf]

Then came another problem- there weren't enough seaplanes to go around.

But look at the bewildering array of aircraft they came up with.  For every requirement, they built a totally new type of aircraft, often utilizing totally new components such as engines and armaments (for example, the USN use naval aircraft or adaptations of Army aircraft for shore-based units, while the IJN ran dedicated projects for land-based aircraft development).  That's not to mention that IJAAF and IJNAF had seemingly totally seperate logistic chains, with their own seperate projects doing the same thing (such as liscence-building DB-601)...... they even developed their own ordnances, which despite being of the same class and doing the same thing share no commonality at all.

Because the IJN's aircraft requirements and usage were almost completely different from those of the IJA. The reasons are very simple, the IJA was equipping for a land war in China, the IJN for a mostly waterborne war throughout the South-East Asia and the Pacific Ocean.

Compare the specifications and mission profiles, no IJA bomber of 1941 could have carried out the long range missions accomplished by the Mitsubishi G3M and G4M. Even with later bombers the range requirement of the IJN aircraft is greater than that of the equivalent IJA aircraft.

In the single engined fighter realm the IJN only commissioned one solely land-based design, the Mitsubishi J2M, only 476 of all types were built. it was the preferred Japanese bomber interceptor.
The Kawanishi N1K()-J series of land based fighters originated as a private venture and turned out to be the IJN's best fighter of the war. The most common land-based fighter was the ubiquitous A6M. Land based attack units used carrier aircraft designs, the IJA had no equivalent aircraft.
The IJN's J1N1 was the only somewhat effective nightfighter fielded by either service, it originated from a shortlived requirement for a long-range escort fighter.
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
A close examination of Japanese aircraft types by service actually reveals surprisingly little overlap in requirements or duplication of effort.

Anyhow the battleship-carrier concept was unwieldy and by the time the conversions were ready to enter service it wouldn't have mattered if they had been able to produce the 'special' aircraft, they were out of pilots. Also the intended seaplane bombers, which were never built, would have been easy meat for Hellcats and Corsairs.

As to modifying standard types rather than new designs, thats what the IJN did with the Zero, interminably.

The other thing to bear in mind is that the Japanese aircraft industry never had the manufacturing capacity or capability of the US and their allies, standardizing on a few given types would not have automatically translated into dramatically increased production, more likely it would have led to decreased production rates from the inevitable delays in transferring engineering data and creating/setting up tooling and production lines. Such a scheme would, very likely, also have put increased pressure on the hundreds of small sub-contractors. The Japanese aircraft industry relied heavily on back-alley cottage industry, and had since its inception post-WWI.
Total Japanese production of all combat types between 1941 and 1945 was 52,242, the US produced 53,183 in 1943 alone.

Jon

[RLBH]

The US Navy, Royal Navy, Kriegsmarine and Soviet Navy all looked at hybrid battleship/aircraft carriers or cruiser/aircraft carriers. They all rejected the idea. The only ones ever to see service were the GOTLAND, designed for a very small navy to fulfil a very specific role, and the ISE and FUSO, out of sheer necessity. What does that say to you?

The Royal Navy's brief study concluded that five hybrid battleship/aircraft carriers could carry thirty 15" guns and 72 aircraft, and require 225,000 tons of shipping. For 200,000 tons, one could get three LIONs, with twenty-seven 16" guns, and three INDOMITABLES, with 144 aircraft. And that was the end of that idea.

Also, ISE and FUSO were intended to carry eight D4Y2 "Judy" wheeled divebombers, and fourteen E16A "Paul" floatplane divebombers. It was an idea which might have had some value in terms of getting aircraft to sea, but the ships would be ineffective as aircraft carriers and too vulnerable as battleships.

[Joe C-P]

Another problem was take-offs. Aircraft couldn't be catapulted straight forward, and they need to be launched into the wind for best results, especially as Ise and Hyuga weren't especially fast. Therefore, the ships would have to turn to port to launch from the starboard catapult, and to starboard to launch from the port side. The whole crew would be green by the time they finished launching the aircraft.

JoeP