Naval Historywith Dr. Alex

Q&A · 47:55-48:21

Sending I-400 submarines to France in 1944

An I-400 transfer from Japan to German bases in France was possible in principle, but the long transit and the demands of sustained operations made it far harder than a simple delivery voyage.

I-400 Class SubmarinesImperial Japanese NavyKriegsmarineNaval LogisticsSubmarine BasesSubmarines
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Question

Could Japan send a pair of I-400-class submarines to the German U-boat bases in France in January 1944?

Short answer

They might complete the transfer, but the journey would be difficult and operating from France would pose a larger problem than merely arriving there.

Notes

The route is possible in principle, but getting the submarines from Japan to occupied France would be difficult. A passage to the U-boat pens would be a demanding wartime journey rather than a routine redeployment. Simply arriving to retrieve material is also a more limited task than basing the boats there as an effective combat force. The answer separates geographic possibility from the much harder problem of sustained operation after arrival.