WI: Proximity Fuse Delayed, Impact On The Battle Of The Philippine Sea And Other Naval Battles?

[GuildedAgeNostalgia]

1. The invention of the Proximity Fuse is arguably one of the most important military inventions that took place during World War Two. It is a fuse that automatically allows a artillery or anti aircraft shell to automatically detonate within a certain distance of a target. When it comes to anti aircraft guns specifically, before the implementation of the Proximity Fuse in naval warfare, it took time fused shells six times as much ammunition to shoot down enemy planes than it did with proximity fuses. Not only that, but the US navy saw a 700% improvement in shooting down enemy kamikazes with the implementation of proximity fuses.

Proximity fuze - Wikipedia

en.wikipedia.org

2. In otl, the deployment of the proximity fuse would come just in time for the Battle of the Philippine Sea, the largest carrier vs carrier battle is naval history. 15 US carriers would go up against 9 Japanese carriers. This battle would for Japan would be a complete disaster however, a large reason for this being that US AA guns having access to proximity fuses, being able to shoot down almost 650 aircraft.

Battle of the Philippine Sea - Wikipedia

en.wikipedia.org

3. So let's say that proximity fuses are not invented until after World War Two. The questions are:
- Does Japan have a chance to win the Battle of the Phillipines Sea?
- Even if they don't, how much more damage can they do during this battle?
- How much more effective will Kamikaze attacks be as well?
- How does this affect any other aspect of World War Two?

4. In at tangent discussion, would it be possible for Japan to invent the proximity fuse first and if so what impact would it have earlier in the war?

 

[Dancing Fool]

So let's say that proximity fuses are not invented until after World War Two. The questions are:
- Does Japan have a chance to win the Battle of the Phillipines Sea?

Yes, they do.

Without the proximity fuse, carrier battles are ADVANTAGE OFFENSE. It’s a roll of the dice and anything can happen.

 

[jlckansas]

Yes, they do.

Without the proximity fuse, carrier battles are ADVANTAGE OFFENSE. It’s a roll of the dice and anything can happen.

No they don't have the amount of aircraft to put up in the attack on the US fleet. The IJN lost the 2 of the CV's before the battle even started, the Taiho and Shokaku, and even before they lost them the US outnumbered them approx 900 to 450 aircraft carrier based aircraft and not all of the IJN were newer model but the same old Zero.

 

[CV12Hornet]

Yes, of the 402 aircraft the Japanese lost at Philippine Sea 366 were lost to fighters and only 19 by anti-air guns. It’ll make no difference.

Now, the Kamikaze threat, on the other hand…

 

[Dancing Fool]

The IJN lost the 2 of the CV's before the battle even started, the Taiho and Shokaku, and even before they lost them the US outnumbered them approx 900 to 450 aircraft carrier based aircraft and not all of the IJN were newer model but the same old Zero.

Okay, in a repeat, Japan might need to avoid losing those two carriers.

But those sheer numbers — 450 to 900 — there’s enough variance that the weaker side can win. Maybe 1 time out of 5, maybe 1 time out of 7. And/or they can do some real damage and strategically withdraw from the battle.

As a strong intermediate poker player, I’m very familiar with the weaker mid-hand winning, sometimes on the very last card!

 

[Sekhmet_D]

- Even if they don't, how much more damage can they do during this battle?

The Japanese bomber crews at Philippine Sea could barely hit the broad side of a barn. Most you'll get is one or two American carriers moderately damaged.

 

[CV12Hornet]

4. In at tangent discussion, would it be possible for Japan to invent the proximity fuse first and if so what impact would it have earlier in the war?

No. Their electronics industry isn't up to snuff for producing radars that small.

 

[Dancing Fool]

Yes, of the 402 aircraft the Japanese lost at Philippine Sea 366 were lost to fighters and only 19 by anti-air guns. It’ll make no difference.

Do you have a handy reference for these fighter vs. anti-aircraft loses?

 

[CV12Hornet]

Do you have a handy reference for these fighter vs. anti-aircraft loses?

Sure:

As the day’s score was being added, the full story was revealed. Although there was bound to be some duplication in reports made in the heat of battle, it was clearly evident that the enemy air force had been nearly wiped out in its attempt to break through our fighter cover. A total of 402 enemy air craft had been destroyed—>366 in aerial combat, nineteen by antiaircraft fire, and seventeen on the ground. Statistically it was the biggest day of the war for our fighters, and historically this, the “Marianas Turkey Shoot,” was the very symbol of our mounting superiority.

https://www.usni.org/magazines/proceedings/1951/february/battle-philippine-sea

Newer sources I have put the total Japanese aerial losses at 476 and have somewhat different numbers for aircraft losses, though they're in agreement that the preponderance of losses were from American fighters:

As the two Japanese carriers struggled to stay afloat, their aircraft were already airborne and heading for the U.S. Fifth Fleet covering the landings at Saipan. In four raids from the nine carriers, 326 Japanese carrier aircraft threw themselves at the 15 carriers (seven fleet and eight light carriers) and seven fast battleships of Vice Admiral Marc Mitscher’s Task Force 58, running into a buzz saw of 450 Hellcat fighters. With the aid of early tactical warning from radio intelligence detachments, and radar-directed intercepts controlled by fighter direction officers in new combat information centers (CIC), the overwhelming numbers of technologically superior Hellcats, flown by much better trained pilots, cut the Japanese formations to ribbons. About 224 of the 326 inbound strikers (the largest Japanese carrier raid of the war since Pearl Harbor) fell to the guns of fighter aces like David McCampbell and Alex Vraciu, along with others who became “ace-in-a-day.”

H-Gram 032

Download a PDF of H-Gram 032 (3 MB).

www.history.navy.mil

 

[GuildedAgeNostalgia]

Now, the Kamikaze threat, on the other hand…

How much worse could it have gotten?

 

[Dancing Fool]

https://www.usni.org/magazines/proceedings/1951/february/battle-philippine-sea

Newer sources I have put the total Japanese aerial losses at 476 and have somewhat different numbers for aircraft losses, though they're in agreement that the preponderance of losses were from American fighters:

Thank you.

Actually, I think the world of proximity fuses. For example, they worked great about 5 weeks into the Nazi V-1 bombing of southern England the Summer of 1944. After chases by dive-bombing human pilots, interfering cables held aloft by balloons, and conventional anti-aircraft all worked merely so-so. Anti-aircraft on the coast with proximity fuses worked quite a bit better than any of these.

All the same, the Battle of the Philippine Sea — June 19 & 20, 1944 — is a major data point, no question.

 

[Band in China]

No they don't have the amount of aircraft to put up in the attack on the US fleet. The IJN lost the 2 of the CV's before the battle even started, the Taiho and Shokaku, and even before they lost them the US outnumbered them approx 900 to 450 aircraft carrier based aircraft and not all of the IJN were newer model but the same old Zero.

Just to add the qualitative advantage of US pilots and aircraft vs the reconstituted IJN pilots and by this point last gen planes widened the gap further, especially in the air.