IJNAF Rikkos- asset or resource waste?

[lancer21]

This is pertaining to the IJNAF land based bombers G3M, G4M and P1Y of which respectively about 1000, 2500 and respectively 1100 were built. Would the IJN been better of to just build single engine carrier planes instead of the rikkos? On one hand the rikkos had enormous range (combat radius with bombs or torpedoes at least 700nm, have i got that right?) and served IJNAF relatively well in China and early Pacific war, and i guess they remained valuable for reconnaissance tasks, but as the opposition got stronger they were slaughtered from 1942 onwards.

On the other hand building say 9000 single engine carrier planes (A6M, D3A, B5N/ B5M, D4Y, B6N, B7A etc etc., not to mention new fighters) instead of the 4600 rikkos would mean at least the IJN carriers would kinda overflow with planes earlier in the war, allowing all the carriers to carry their maximum rated number of planes for longer, and even have a decent reserve in the process, again at least for a while. The balance could still be used to create land based groups at least as numerous as the OTL rikko groups but equipped with kankos or kanbakus, on the other hand their combat radius is considerably less at about 300 nm, maybe a bit more of later war models (closer to 400nm, again have i got that right?)

Also, the design resources saved by not building rikkos could perhaps be used to bring forward the new generation of carrier planes, for instance no reason why a 1500HP Kasei powered B6M (instead of the OTL B6N Tenzan) can't be in service in 1941? Again new carrier fighters could appear earlier, like a 1942 Mitsubishi A7M (instead of the J2M), or even a Nakajima A7N instead of the G5N and J1N or a Yokosuka A8Y instead of P1Y etc. etc. The limitation being the power of the engines available.

And yeah since i touched the J1N, i would rather have 1000 A6Ms than 500 J1Ns, no need for twin engined fighters if there are no rikkos.

So what you guys make of all this?

 

[kaiserd]

There are always trade-offs in one class of aircraft versus another.

An there can sometimes be a debate (contemporary and/or retrospective) on if the balance of resource allocation across theses classes proved to be optimal (say, for the mosquito versus the Lancaster and other 4 engined bombers for the WW2 RAF).

However it is very important to note that different classes of aircraft have different roles and purposes. They are likely not as effective at doing each other’s roles.
The Japanese Navy’s medium bomber fleet had a wider bomber role than just going after an opponents naval fleet and the combination of payload and range can’t be substituted by more single engined carrier planes. And Japan can’t just produce more carriers for such extra planes to operate from, obtain more convenient land based for them to fly from, or magic out of air extra pilots to fly them.

So as a theoretical thought experiment; knock yourself out.

However as anything like a realistic realisable scenario; very much not.

 

[Archibald]

Big problem for the Japanese in WWII: they can't renew their elite pilotes fast enough - or at all.
The ones that attacked Pearl Harbor and until 1943 were a well trained elite... that was too small and could not be renewed.
Building more carrier-borne bombers may be useful but would ran head-on into that problem.

 

[lancer21]

Regarding the issues of pilots, actually given that a rikko has a crew of 7, it quite neatly work to have two kankos or kanbakus (crew of 2 or 3) for every rikko, without having to train any more aircrew than OTL. At least early in the war the rikko crews were very well trained, veterans of the war in China etc, in fact i have to recheck but i have read somewhere that before the war it was the rikko units who were seen as the top elite of IJNAF rather than the carrier squadrons!

As to the IJN carriers themselves there are various ATL timelines about them, imo it is possible to improve the situation even a little bit without diverting too much from the historical IJN aquisition process, but even small chages can have a huge effect in the critical year 1942 for IJN carrier fortunes.

I do agree that there is the problem of the shorter range of the single engine planes, and the airfield issue as well, in theory they would just to work the carriers even harder to take at least some of the missions historically performed, and work harder where in setting up airfields closer to their objectives in order to use the land based units.

For instance for the Phillipines campaign they could attack the airfields around Manilla from some carriers (the CVLs were intially planned to do this at first anyway), while acting to get control of the northern airstrips such as Aparri, Vigan etc to transfer the land based units there so they can be used against Manilla (this is what IJAAF had to do anyway because of their shorter ranged planes).

But i don't know what would happen (if anything) to Force Z though if there were no rikkos, unless of course there were some japanese CVLs assigned to that operation? Same goes for IJNAF air operations against Australia other than those undertaken by Kido Butai.

 

[EwenS]

Regarding the issues of pilots, actually given that a rikko has a crew of 7, it quite neatly work to have two kankos or kanbakus (crew of 2 or 3) for every rikko, without having to train any more aircrew than OTL. At least early in the war the rikko crews were very well trained, veterans of the war in China etc, in fact i have to recheck but i have read somewhere that before the war it was the rikko units who were seen as the top elite of IJNAF rather than the carrier squadrons!

Unfortunately it is not so simple. 1 Rikko = 2 pilots but only 1 trained navigator and 1 trained radio operator and 1 trained engine mechanic plus 2 gunners.