Question about IJN Shinano Air Group.

[chuck]

Shiden's mid-wing configuration forced its landing gears to be very tall, complex and fragile. It's unlikely to make many successful carrier landings. Shiden Kai might make a better carrier plane. A jet Shinden would also make a very poor carrier plane because early jet engines lacked the standing start thrust to allow take off from carrier deck unassisted. The Japanese never developed flush deck catapults, and always relied on wind over deck and high standing start power of piston engines to take off.

[Sauragnmon]

I didn't know if they had a navalized version of the Shiden, since far as I know it was land based only... and as to the Shinden making carrier landings, if you forgo the hook, you could have made a decent possibility of a carrier landing with nosewind, full flaps, and low approach velocity, just enough to keep the plane flying without a stall. It'd be a ballsy move, but you could probably teach the pilots that threshold and bring it into operation. It's a matter of how you approach it. You come in barely over the deck and practically stall it right onto the deck. With enough work, you could develop a doctrine of use, barring the application of a hook into the design. It wouldn't be impossible to reinforce and render the gear struts and such more sturdy on the Shinden to prevent accidents.

[chuck]

Shinden's long nose would give its pilot poor over-the-nose visibility, which would discourage the sort of ambitious landing moves you describe. Once you factor in the fact that the remaining average Japanese pilot had less than 20 hours of cockpit time, it seem such moves would be exceedingly unlikely to succeed.

[Dan K]

Chuck is correct in that the low wing version was known as the Shiden-Kai. That's what I am referring to. see: http://en.wikipedia.org/wiki/Kawanishi_N1K-J

[ninjrk]

Les, I think this description of Shinano's planned employment (and I have read this version, too) is a misinterpretation of the actual plan. My understanding is she was to operate in the van 100-200 miles ahead of the main carrier force. The attack force would arm and launch from Amagi types in the rear and refuel during a stopover on Shinano before (or after) hitting the target. She would have used her size and strength to absorb punishment which the Amagis couldn't.

That's correct. The original idea that the Shinano would be an aircraft transport isn't backed up by the Japanese extant plans for her. It's not exactly an error, as by the time the design was completed there weren't enough carriers to use her as a protected forward base, so her actual use was pretty much as a transport. However, the intent was that she would be a refueling/rearming stop that could take a lot of punishment while other carriers (presumably Unryu's) lurked well behind her.

Matt

[chuck]

The strange theories about how Shinano would be used all sound to me like Crockpot excuses cooked up during the bureaucratic in-fighting within IJN by the fraction advocating her conversion. The conversion of Shinano is really a somewhat questionable proposition. She would have been 2.5 times larger than the Taiho and yet possess no clear additional merit over the smaller carrier. I suspect there would have been opposition within IJN to her conversion. So the conversion advocates would likely cook up strange excuses, totally unrelated to their real intentions, to justify the project. However, in reality, If Japan still had trained crews and air craft remaining when she was finished, I think it's almost 100% certain that she would be employed just like a normal fleet carrier.

[Lesforan]

Just speculating now, I suspect Chuck is right on this. Shinano would have way too much potential as an attack carrier to have any other primary role.

I don't think the concept of using her as a forward refueling stop would have worked out well in practice. Any carrier is at its most vulnerable when recovering planes, and to put her out ahead of the main carrier force would be an invitation to disaster.

The fact that she was loaded with Okha aircraft when sunk supports the idea of using her as an aircraft transport. This theory could have been developed after the fact, but for what purpose I can't see.

[Werner]

Yes, it's one thing to propose a major shift in doctrine around this ship, and quite another to implement it, especially without trying the process out in training.

I also don't much like the idea of landing all these armed attack planes on Shinano to refuel. A flight deck accident could potentially wipe out the ship and another ship's air wing.

[bengtsson]

Les, I think this description of Shinano's planned employment (and I have read this version, too) is a misinterpretation of the actual plan. My understanding is she was to operate in the van 100-200 miles ahead of the main carrier force. The attack force would arm and launch from Amagi types in the rear and refuel during a stopover on Shinano before (or after) hitting the target. She would have used her size and strength to absorb punishment which the Amagis couldn't.

Looks like the Japanese did love making plans didn't they ? If the ship ever did get a chance to operate in action, it's most likely it wouldn't have been in such a set piece type of operation. If you are superior, you can arrange set piece battles, is you are running for your life, it is catch as catch can.
On a side point, the Japaese did have very progressive ideas about using land based and carrier bases planes to stage in or out of action. All planes being carrier capable.
Shinano is a very interesting ship. Was she capable of holding large air groups or could she only stage large airgroups in and out???


Bob B.

[Lesforan]

I think if the Japanese really wanted to use Shinano as a refuelling station, it would have behooved them to do a little research into mid-air refuelling. This technology was first put to practical use before WWII, at Key Field in Meridian, MS.
While fuel was successfully transferred between planes in mid-air, the aircraft were civil craft. I don't think the military tried this until after WWII, but the technology did exist. Shinano used as a floating tanker station would have been more practical than landing loaded strike aircraft on their way to a target. Alternatively, the aircraft could have been flown from their home carriers with no weapons and only enough fuel to make a one-way flight to Shinano. Shinano could then arm them and refuel them.

The problem of a big, fat target out ahead of the fleet would remain.

Far better they use Shinano as a heavy strike carrier, replacing two or three conventional fleet carriers. Her huge flight deck would have allowed the use of twin-engine aircraft. Finish her sisters Yamato, Mushashi, and the unnamed hull as sister carriers, and Japan might have been able to launch Pearl-Harbor size attacks around the Pacific and Indian Oceans simultaneously, keeping the regular fleet carriers in reserve. Perhaps the Japanese could have developed a twin-engine ASW aircraft for use from these ships, something they sorely needed.

We need to remember the Shinano was pretty much a close match to the Forestall Class in size, with heavier armor protection.

[Werner]

Shinano's hangar space was limited compared with the other carriers. On the other hand, after Midway the Japanese recognized the fatal error of fueling and arming aircraft in a sealed, but unarmored hangar (as it turned out, Taiho would prove even an armored flight deck did not provide sufficient security) and began to move toward operating the wing strictly on the flight deck, like the Americans. My guess is in American practice, Shinano ought to be good for 100 aircraft. Unfortunately for the Japanese, first class airframes and pilots were not available in such quantities.

[Werner]

Shinano's hangar space was limited compared with the other carriers. On the other hand, after Midway the Japanese recognized the fatal error of fueling and arming aircraft in a sealed, but unarmored hangar (as it turned out, Taiho would prove even an armored flight deck did not provide sufficient security) and began to move toward operating the wing strictly on the flight deck, like the Americans. My guess is in American practice, Shinano ought to be good for 100 aircraft. Unfortunately for the Japanese, first class airframes and pilots were not available in such quantities.

[chuck]

We need to remember the Shinano was pretty much a close match to the Forestall Class in size, with heavier armor protection.

Not where it really counts. Shinano's deck was considerably shorter and much, much smaller. The conversion Shinano undertook was by no means as comprehensive as previous Japanese battleship to carrier conversions such as Akagi and Kaga. The net result is Shinano became a half-assed carrier built up by stacking the aviation facilities of the much smaller Taiho on top of the weather deck of an slightly modified Yamato hull. By no means is the full load carrying capacity of the Yamato hull fully and optimally utilized to enhance aviation capacity. If the Japanese had done it right, they would have:

1. Give the ship enclosed hurrican bow to facilitate a longer hanger deck and longer forward flight deck

2. Give the ship a Ark Royal type stern to facilitate a flight deck extension to the rear, and give the ship a 1000 foot flight deck she could easily support

3. Reworked the Yamato hull to move the armor deck down one deck level, so the hanger deck and the flight deck can be moved down one deck as well. This would reduce the top weight, enable the flight deck to be more heavily armored, and allow the flight deck to be extended beyond the width of the Yamato hull.

[Lesforan]

Yes, they failed to take full advantage of the potential the Shinano offered. They had the opportunity to build the most powerful aircraft carrier in the world. Good thing for us they didn't.

To do the conversion you described, they should have begun work earlier than they did. Aparently, Shinano was converted as an afterthought. Like the Germans, if the Japanese had waited only a few more years they would have been much better armed. We can only speculate on what weapons Japan and Germany would have had with a few more years' lead time, but from what we have been able to find, they would have been formidable against what the Allies actually had by then. Axis design and R&D kept moving forward, but the production capacity and access to strategic materials steadily declined.

I don't think it is beyond the realm of possibility that the Japanese would have developed a good catapult system. British and US flush-deck cat systems could have been copied. This would have been much better than the Rube Goldberg system the Germans tried to employ.

[bengtsson]

Shinano's hangar space was limited compared with the other carriers. On the other hand, after Midway the Japanese recognized the fatal error of fueling and arming aircraft in a sealed, but unarmored hangar (as it turned out, Taiho would prove even an armored flight deck did not provide sufficient security) and began to move toward operating the wing strictly on the flight deck, like the Americans. .

Werner,
I thought in 1942 the USN often armed and gases planes on the hanger deck. The open hanger design allowed good venting of fumes. When did the USN move away from arming, gasing and holding planes on the hanger deck? I admit, USN Carrier practice after 1942 is not a subject I've much knowledge of.
The japanese had vent systems for their hanger decks, but they were not really up to the job.

Bob B.

[chuck]

(as it turned out, Taiho would prove even an armored flight deck did not provide sufficient security).

Taiho's armored deck was never tested. Taiho's demise shows that ability to provide on-demand natural ventilation in the hanger is a good thing, and putting the hanger deck on the same mechanical ventilation system as the rest of the ship can be deadly.

[chuck]

Shinano suffers from the following drawback as a very large carrier: The Japanese deck launch practice relies on the deck crew pulling each aircraft onto a designated spot, arranged 3 abreast. The pilot than uses his own judgement to steer the aircraft onto the centerline of the ship and take off. Although Shinano's deck is considerably wider than Taiho's, it is unfortunately not really wide enough to spot aircraft 4 abreast. Thus a deckful of planes ready to launch on the Shinano would contain no more planes than a deck full of planes ready to launch on the Taiho. What is more is Taiho being a substantially faster ship can generate significantly higher wind over deck, and can thus spot aircraft closer to the front extremity of the deck. Shinano's deck is the same length as Taiho's, consequently Shinano must actually leave more deck space vacant in the front than Taiho during launch operation, and can spot airccraft over a shorter length than Taiho.

So the upshot is Shinano can not effectively operate more aircraft than Taiho, despite her size. When all is said and done, the Shinano conversion can not be judged successful. The potential of a 70,000 ton hull was not even close to being realized.

[HMAS]

AFAIK the Shinano operated 47 aircraft, & they were for her own defence.
other aircaft were onboard in crated form / spare parts etc
the removal of the 18" guns required several tons of concrete to be dumped into the hull to counter the weight loss, & also concrete fuel tanks for av-gas?
Tony

[Werner]

Let's remember, Shinano never became active; she was still being finished when she was sunk. One story said her material condition was very low owing to watertight fittings not being installed yet.

[Sean Hert]

Shinano was being used to ferry a/c at the time of her demise, right?