The Aircraft Carrier War

[Art]

New aircraft carriers post 1943; both the United States and Japan made aircraft carrier production a highest priority after the losses of the 1942 battles.

Japanese Aircraft Carriers:

For the Japanese these come in two varieties, those built which actually carried air wings and those which were completed after Japanese naval aviation ceased to exist. Those that were finished in time to carry air wings:

Taiho CV
27,700 tons
33 Knots
65 Aircraft

This is an interesting one. It was an armored carrier similar to the British ones. The Japanese intended to make more of these but construction was too expensive and they took too long to build.

Chitose class CVL
Chiyoda
Converted sea plane tenders
11,900 tons
30 Aircraft
29 Knots

These never carried an air group and spent most of their careers bobbing around the inland sea.

Unryu Class CV
Amagi
Katsugiri
22, 534 tons
34 Knots
65 Aircraft

Unryu was sunk by an American submarine while being used as a high speed supply ship hauling cargo to the Philippines.

Shinano CV
Converted battleship
71,859 tons
55 Aircraft
27 Knots

Shinano was actually a combination carrier/depot ship made to support other carriers, thus its relatively small air group. Sunk by an American submarine on a shakedown cruise.

American Carriers:

Essex Class CV

24 total construction 13 of which were built in time to see significant service in WW II.
27,100 tons
90-100 Aircraft
33 Knots

Independence class CVL
Converted light cruisers
9 ships, all commissioned in 1943
11,000 Tons
33 Aircraft
31 Knots

[barretcreek]

Art,
Will you go into the manner by which we were able to turn out increasing numbers of fairly competent fledgling aviators while IJN was not?

[Art]

Art,
Will you go into the manner by which we were able to turn out increasing numbers of fairly competent fledgling aviators while IJN was not?

I mentioned that in a previous post but, essentially, the Japanese navy was running on empty on pilots by late 1943, and their program for new guys was by necessity more abbreviated and suffered from a lack of experienced men as instructors. We on the other hand had a lot more of the pilots we started the war with in 1943 and many of these men were rotated back as instructors. This gave us the luxury of being able to do a much more comprehensive training program for new pilots. Our new pilots who started to appear in mid - late 1943 were much better trained because we weren't in the desperation mode the Japanese were. Our new pilots obtained valuable experience in the southwest Pacific and the island hopping campaign along side an experienced corps of veterans.

When the Japanese started showing films in movie theaters recruiting pilots it was a sign they were in trouble. We never had a shortage of volunteers who wanted to fly.

[Art]

Aircraft post 1942. New models and a major upgrade.

Top speeds are WEP (war emergency power.) Range is combat radius.

The Americans

The SB2C Helldiver
Crew 2: Pilot, Radio Operator Gunner
Speed : 295 mph
Range : 300 miles
Armament: 2x20mm cannon in the wings. 2x.30 cal. machine guns in rear upper fuselage, 4x.50 cal. machine guns in underwing pods (optional.) 2,000 bombs in a bomb bay or 1 torpedo, 8 High Velocity Aerial Rockets.

"The last dive bomber" had a long and troubled (some would say scandal plagued) development that led to investigations and congressional hearings. It has been argued that it was only marginally superior to the SBD Dauntless dive bomber it replaced. In fact at the "Battle of the Philippine Sea" where both types were engaged there were more losses of Helldivers than Dauntlesses.

The F6F Hellcat

Crew : Pilot
Speed : 391 mph
Rate of climb : 2,600 feet per minute
Range : 820 miles
Armament : 6x.50 cal. machine guns.

Superior to all models of the Zero it was designed to defeat in every area except low speed maneuverability and climb rate it was the master of the Japanese fighter once it came into service in 1943.

F4U1D Corsair

Crew : 1 Pilot
Speed: 425 mph
Climb : 3,200 fpm
Range: 800 miles
Armament: 6x.50 machine guns.

Not assigned to US carriers until late in the war, after the Brits had proven it capable of operating from them with some margin of safety.

The Japanese

The Nakajima B6N "Jill"

Crew : 3 Pilot, Observer/Bombardier/Navigator, Radio Operator / Gunner
Speed : 300 mph
Range: 900 miles
Armament: 1 7,7mm machine gun in rear cockpit, 1 7.7 mm machine gun in ventral tunnel. 1 Type 91 Torpedo, or 1,700 pounds of bombs, or 2,250 pounds of bombs (suicide attacker)

The replacement for the B5N Kate it was slow in development and never completely replaced it.

The Yokusuka D4Y "Judy"

Crew : 2 Pilot, Radio Operator/ Gunner
Speed: 340 mph
Range: 800 miles
Armament: 2 forward firing 7.7 mm machine guns, 1 7.7mm machine gun in rear cockpit, 1,100 pounds of bombs or 1,800 pounds of bombs (suicide attacker)

Replacement for the D3Y "Val" dive bomber it proved too heavy to operate off of some light carriers so the Val soldiered on. Due to its very high speed for a bomber it was sometimes used as a night fighter from land bases.

The A6M5 Zero series
Crew : 1 Pilot
Speed: 351 mph (365 mph WEP)
Rate of Climb: 3,300 fpm
Range: 900 miles
Armament: 1 13.2mm and 1 7,7mm mg in upper cowling, 2 x 20 mm cannon in the wings.

An attempt to remedy the deficiencies of the earlier Zeros. The wings were shortened and skin was thickened to improve dive speed taking "never exceed speed" from 360 mph in earlier versions to 410 to 460 mph depending on the variation of the A6M5 series making it capable of an actual dive. The 20 mm cannon were upgraded with a rate of fire increase from about 550 rounds per minute to 750 rounds per minute and an increase in ammunition from 60 to 125 rounds per gun. An armored wind screen and later armor for the pilots back were also added as were fire extinguishers for the wing fuel tanks. It was still inferior to both the Hellcat and later to the Corsair. Inferior Japanese pilots post 1943 didn't help either.

[Art]

The Battle of the Philippine Sea, June 19-20 1944

Sorry for the delay getting back to this.

In the Summer of 1944 nearly 20 months had passed since the last battle between us and Japanese carrier forces. Both sides had been severely mauled in the carrier battles of 1942 and spent the time refitting and re equipping. The industrial power of the United States was beginning to tell as they were almost mass producing aircraft carriers, not to mention aircraft for them. US Pilots were better trained, had more combat experience and there were a lot more of them. On the other hand, the Japanese were mostly making up lost carrier tonnage by converting existing ships. They had had heavy aircraft losses, and more important heavy losses of pilots in the carrier battles of 1942 and the air battles of the South Pacific in 1943.

The Japanese had always counted on decisively winning a battle that would force the Americans into negotiations, and had had two unsuccessful bights of the apple at Pearl Harbor and Midway. The new decisive battle was to be on the ring of defenses that went through the Palaus and Carolines up through the Marianas.

The Americans got a big "heads up" when the Japanese plans were found by a Philippino Guerilla after the plane carrying them crashed. The Japanese plan was to destroy the fast carrier strike forces of the United States. The Americans assumed (incorrectly) that Japanese intentions were purely opposing the U.S. Invasion.

On June 12 US Airstrikes hit the island of Saipan. The Japanese Combined Fleet sortied as soon as it could raise steam. It's carrier striking force consisted of three squadrons of carrier grouped by size and speed. The three biggest and fastest carriers, Shokaku, Zuikaku, and the brand new Taiho formed the First Squadron, three fast light carriers formed another and the two slower fleet carriers, Hiyo and Junyo along with an equally slow light carrier formed the third. They embarked about 540 aircraft, almost all new or upgraded types. In addition the Japanese could count on about three hundred aircraft of all types based in the Mariannas. The Americans deployed four groups of carriers. All had 2 CV, and CVL except for one which had one CV and 2 CVL. The American carriers embarked about 900 aircraft.

The Japanese counted on the range advantage of their aircraft and the bases in the Marianas to allow them to hit without being hit back

American submarines detected the Japanese on the 15th.

With the priority to protect the beach head on Saipan the slow battleships and escort carriers were assigned to protect the landings. The fast carriers to engage the Japanese. A "gun line" of fast battleships. cruisers and destroyers was placed between the Japanese and the carriers to engage any Japanese aircraft that got through the combat air patrol.

On the morning of the 19th of June, before sunrise, the Japanese began a search for the American Carriers. A Zero carrying a bomb found the Americans, radioed their position, began a bombing run on a picket destroyer and was promptly shot down.

The Japanese then launched an attack with their land based aircraft which resulted in the loss of over 30 of their aircraft in exchange for one Hellcat. At about the same time the first carrier strike was detected on US radar, the fighters were recalled and vectored to the incoming strike (American problems with coordinating their CAP had been completely solved.) Four Japanese strikes resulted in 361 aircraft lost in aerial combat or to the anti aircraft fire of the "gun line" and the carriers and their screen, in exchange for a hand full of US losses. The problem the US had, though, was the Japanese were well outside the range of US search aircraft so remained undetected.

The Japanese were out of range of US scout aircraft but not US Submarines. USS Albacore put a single torpedo into the Taiho. This should have been easily survivable but the losses of Japanese technicians and mechanics included damage control. Taiho's damage control officer was very young and very inexperienced. Without going into detail every decision he made made the situation worse. Six hours after being hit a massive fuel vapor explosion destroyed the ship.

The USS Cavalla later put four torpedoes into the Shokaku. Never a lucky ship (she seemed to take damage in every engagement,) the Shokaku's luck ran out completely. This time her wounds were not survivable and she joined Taiho on the bottom.

Even with only 150 combat worthy aircraft remaining the Japanese decided to continue the battle but late in the afternoon an American scout found the Japanese at the extreme limit of the range of American aircraft. The Americans launched 250 aircraft at extreme range before getting an update that the Japanese were already, essentially out of range. The first strike was allowed to continue but a second cancelled. The Japanese had 35 Zeros in their CAP which was pretty good by 1942 standards but even though they were ably handled by the best remaining pilots, no where near capable of dealing with this strike. The Americans sank the Carrier Hiyo, and damaged some other ships. After subtracting the planes lost to the Americans in combat in this strike and the ones that went down with the Hiyo the Japanese had less than 50 aircraft left.

Japan had lost its last real task force. It still had carriers and would build more but would never come close to reconstituting its air groups.

After the war, when Adm. Jisuboro Ozawa who commanded the carriers at the Philippine Sea, was asked, after the war, about the quality of Japanese aircraft and pilots over the course of the war; his reply was "the planes got better the pilots got worse." This was true of Japanese naval personnel overall, they simply could not replace personnel with men of equal quality.

[rayg]

Thanks for the great posts Art..

[Dan in NH]

Great post Art. I enjoyed reading it

[barretcreek]

Thank You, Art. Great post.

[blackhawknj]

IJN Taiho was sunk by a single torpedo in the Battle of the Phillipine Sea.
There were the USS Sable and USS Wolverine-the only coal fired freshwater aircraft carriers. They were used to train pilots in takeoffs and landings, deck crews.

[Art]

Quick note, the survivability of British carriers wasn't just due to their armored decks. Their aviation gasoline was was stored in cylindrical tanks in cofferdams filled with sea water. American and Japanese carriers had steel tanks attached to the structure of the ship which allowed them to carry more fuel but made them vulnerable to cracking when bombs, or Torpedoes hit the ships. The great killer of American and Japanese carriers was their own aviation fuel leaking from cracked tanks and vaporizing after bomb, or especially torpedo hits.