Hacker News Reader

Comment by piqufoh | Hacker News Reader

> But by 1943, the tides had turned in their favor.

> There is a clear inflection point around March 1943: From this point onward, the Allied forces sank more ships every month than they lost.

Any idea what what happened early 1943? Was there a specific event that changed the direction, or is the balance point of slow attrition?

View on HN

If you look at the Pacific Theater, the inflection point is later, really amping up in late 1943.

I'd imagine a one contributing factor is fixing the ridiculously buggy Mark 14 torpedo, which cleared up right about that time: https://en.wikipedia.org/wiki/Mark_14_torpedo

Here's a great video on it: https://youtu.be/eQ5Ru7Zu_1I?si=_1ujGsLQumraKz1Q

May of 1943 was called Black May because so many U-Boats were sunk, 25% of the force.

The reason was a bunch of technologies coming together. New weapons like Hedgehog and new tactics. More escorts and better ones. The Mid-Atlantic gap was closed by B-24s, there were more escort carriers.

Colossus the computer created to crack Enigma was released in 1943, that’s probably the cause:

https://en.m.wikipedia.org/wiki/Colossus_computer

Slight correction: according to Wikipedia, Colossus was based on the machine used to crack Enigma: https://en.m.wikipedia.org/wiki/Bombe

However, the timeframe matched, so around 1943, the Allies could decipher messages that allowed them to anticipate German naval movements.

I thought the German subs used more sophisticated encryption and were more disciplined in operational procedure such that the subs were largely not decrypted by the Allies.

More a factor against Germany AFAIU. Japan relied on code books, not crytographic mechanisms.

Japanese Empirical codes were cracked dating to the beginning of the war AFAIU, or at the very least 1942.

> what happened early 1943

Supposedly the better question is why it took so long for an allied victory. Britain’s economic output was absolutely vast, and its colonies made it very powerful. Yet it still took the US industrial capacity coming online and a significant portion of the USSR’s population dying before victory.

This book discusses it at length, it’s an interesting read. https://www.amazon.co.uk/Britains-War-Machine-Weapons-Resour...

It's a silly thing to say, because ship losses are largely driven by German submarines in the Atlantic and American submarines in the Pacific, which are about as disconnected as things get in WW2.

You can see clear trends in the data in each of those theatres, both of which turn drastically in the Allies favor later in the war. The main driver for that is American war materiel production, but there's also plenty of decisions in strategy, tactics, and weapons systems that are entirely different.

If you look at the graphs there is nothing like an 'inflection point' or qualitative change in the graph behaviour.

The Allied line goes slowly down and the Axis line goes slowly up. At one point they cross, but there's nothing particularly significant about that crossing point. Nothing happened in the month that they crossed other than the two numbers were equal momentarily.

https://www.history.navy.mil/about-us/leadership/director/di...

Things went pretty badly for the Allies for the first few year, then:

Battle of Midway - June 1942

Allied Victory at El Alamein - November 1942

German surrender at Stalingrad - February 1943

It was all downhill for the Axis powers after that.

I would add to an already great list:

Guadalcanal - August 1942 onwards. The Japanese were turned back here, both their army and navy.

4-rotor Enigma was broken in Dec 1942.

Reply on news.ycombinator.com