USS Yorktown (CV-5) v. HMS Illustrious v. Soryu?

[Amsel]

CV5 was not a Midway class carrier. Those came later. The Yorktown class were the pick of the litter, at that time, particularly in the PTO. The British carriers were not well fitted for the Pacific and they needed armored flight decks because they had no fighters that could defend them until they got them from the US, thanks to the RAF. The Japanese carriers were not designed as well as the Yorktown class as far as getting strikes into the air. That acted as a force multiplier for the Yorktown class.

Thanks Renrich, but if your refering to my comments about the Midway class being laid down as an open hanger carrier, I was refering to the choice being made after Midway to not go to the armored box hanger on the newer vessels. I agree about the force multiplier of more sorties faster.

The Illustrious was more suited for the North Atlantic where rough weather and more darkness made it superior. But in the massive naval campaign of the South Pacific it wouldv'e been at a disadvantage. I know there was better RN CV's then the Illustrious.

 

[Glider]

This is a little missleading. I do not disagree with you when you say that going from two hanger deck (Ark Royal) to one (Illustrious) was a mistake, but they did get a lot right Heavy AA guns, Multiple directors, a significant number of Light AA guns, increased protection of the hanger area.

The Yorktown could not be refitted for obvious reasons but the Enterprise by wars end was fitted with 8-5 3/8's guns, 40-40mm Bofors, and 50- 20mm Orlikon's as her hanger defense. The Bofors are arguably the best AA of the war for ship protection.

Again I don't dispute your numbers but for AA defence the Illustrious had a much heavier AA defence when they came into service and matched the Yorktown at the end of the war. Even the pre war Ark Royal carried 46 x 2pd (6x8) and 32 x HMG
The class varied quite a lot as they tended to be armed with what was available at the time

They all carried 16 x 4.5 with 4 directors
At war end the LAA varied
Illustrious 40 x 2pd (5x8), 3 x 40 (3x1), 52 x 20mm
Victorious 40 x 2pd (5x8), 21 x 40 (2x4, 2x2, 9x1), 45 x 20mm
Formidable 48 x 2pd (6x8), 12 x 40 (12x1), 34 x 20mm
These were a pretty fair match for the weapons carried on the Enterprise.

The difference was that the Illustrious didn't need alterations to cater for the additional topweight.

On the topic of tactics I totally agree that British hadn't grasped the concept of a fleet naval air action in the same way as the IJN or the USN, but it wasn't the fault of the ships.

 

[Glider]

Can anyone tell me why I get 8 when typing an eight?

 

[Glider]

This is a little missleading. I do not disagree with you when you say that going from two hanger deck (Ark Royal) to one (Illustrious) was a mistake, but they did get a lot right Heavy AA guns, Multiple directors, a significant number of Light AA guns, increased protection of the hanger area.

The Yorktown could not be refitted for obvious reasons but the Enterprise by wars end was fitted with 8-5 3/8's guns, 40-40mm Bofors, and 50- 20mm Orlikon's as her hanger defense. The Bofors are arguably the best AA of the war for ship protection.

Again I don't dispute your numbers but for AA defence the Illustrious had a much heavier AA defence when they came into service and matched the Yorktown at the end of the war. Even the pre war Ark Royal carried 46 x 2pd (6x 8 ) and 32 x HMG
The class varied quite a lot as they tended to be armed with what was available at the time

They all carried 16 x 4.5 with 4 directors
At war end the LAA varied
Illustrious 40 x 2pd (5x 8 ), 3 x 40 (3x1), 52 x 20mm
Victorious 40 x 2pd (5x 8 ), 21 x 40 (2x4, 2x2, 9x1), 45 x 20mm
Formidable 48 x 2pd (6x 8 ), 12 x 40 (12x1), 34 x 20mm
These were a pretty fair match for the weapons carried on the Enterprise.

The difference was that the Illustrious didn't need alterations to cater for the additional topweight.

On the topic of tactics I totally agree that British hadn't grasped the concept of a fleet naval air action in the same way as the IJN or the USN, but it wasn't the fault of the ships.

 

[syscom3]

.... The Bofors are arguably the best AA of the war for ship protection.

The 5"/38's with proximity fuses turned out to be the best.

The Midway class after the war ended had nothing but 5".

 

[R Leonard]

Whilst the Yorktown had a theoretical total of 90 aircraft, her operational maximum was in fact closer to 72. The Soryu had a theoretical maximum of 72, but an operational maximum of 63 aircraft.

Contrary to either the Japanese or the US, the Illustrious had a theoretical maximum of only 40, and this was the number she fought most of the war with. However, in 1944, it was found that by maintaining a permanent deck park, she could operate up to 52. This was the CAG that the Illustrious class carried into the final battles in the Pacific

So in the end, the operational maximums of the three classes are: Yorktown 72, Soryu 63, and Illustrious 52.

If you're going to reach into 1945, let us look to USS Enterprise, the only Yorktown class carrier to survive the war. Drawing from USN aircraft location reports:

Average Jan – Dec 1942 Air Group
27 VF
36 VSB
14 VT
77 Total

Average Jan – Dec 1943 Air Group
36 VF
34 VSB
17 VT
87 Total

Average Jan – Nov 1944 Air Group
40 VF
28 VSB
18 VT
86 Total

Average Dec 1944 – Aug 1945 Night Air Group
35 VF
25 VT
60 Total

Average Jan 1942 – Nov 1944 Day Air Group
34 VF
33 VSB
16 VT
83 Total

Overall Average Air Group
33 VF
32 VSB
18 VT
83 Total

Operating as a regular day fleet carrier, a Yorktown class could operate quite a bit more than your noted 72. Note also that the USN carriers were already using a deck park as standard doctrine, they always had. RN carriers had to adopt the deck park in order to significantly enlarge their air group complements. Any other increases in air group complements were driven by the aircraft themselves

You are, then, IMO, mixing apples and oranges in the same basket; capacity goes down with non folding wing SBD's and F4F-3's. TBD's, with their wings folded, are pretty much even width-wise with TBF/TBM's with theirs folded.

Average Air Group with F4F-3's, TBD's, and SBD's (roughly Dec 41 through Apr 42)
18 VF
36 VSB
18 VT
72 Total

Average Air Group with F4F-4's, TBD's, and SBD's(roughly May 42 through Jul 42)
28 VF
33 VSB
16 VT
77 Total

Average Air Group with F4F-4's, TBF's, and SBD's (roughly Aug 42 through Apr 43)
36 VF
35 VSB
12 VT
88 Total

Average Air Group with F4U's, TBF's, and SBD's (May Jun 1943)
39 VF
38 VSB
20 VT
97 Total

Average Air Group with F6Fs, TBFs, and SBDs (roughly Jul 1943 to Jul 1944)
37 VF
30 VSB
18 VT
85 Total

Average Air Group with F6F's, TBF's, and SB2C's (roughly Aug 1944 through Nov 1944)
43 VF
32 VSB
19 VT
94 Total

Average Air Group as Night Operations carrier, F6F's and TBM's (Dec 1944 through Aug 1945 – does not include subtractions for aircraft lost incidental to damage to ship nor yard time with no air group assigned)
35 VF
25 VT
60 Total

And, of course the reduced strength CVG(N) was still larger than the deck-parked Illustrious' air group of 52 in 1945.

In terms of defensive capability there is no comparison. The Illustrious class, and the light fleet carriers that followed them and adopted the same closed hangar system, were far superior to anything the US possessed, including the Essex classes until long after the war. There were reasons why most post war minor navies went for British Carriers and US aircraft after in their postwar navies

Two different theories of ship defense. One, protect against the inevitable bomb hit, the other, try to prevent the bomb hit. Yorktown, I'd point out, did pretty well, DC wise, even when hit by bombs at Coral Sea and at Midway. Again, apples and oranges. Also that after WWII I think you would find that a few navies acquired US built carriers as well. Most of the RN carriers exported went to Commonwealth nations, most of the other nations picked up USN carriers, albeit none of the CV's as the US was not about to let them go. You don't suppose there were any economic and political issues involved in Commonwealth carrier decisions, do you?

Had Soryu survived the Midway debacle, her defensive capabilities would have been significantly improved as were all the Japanese carriers. though never as well protected as either the US or the british carriers, the Japanese after Midway were quick to adopt CO2 gas lines, and other damage control measures that significantly reduced the risk of fires that had so badly devastated all the carriers at Midway. In 1944 this problem returned when the Japanese were forced to utilise highly volatile unrefined crude from Balipapaan and Tarakan. This fuel was apparently much more volatile than refined fuel, and the result was the repeat debacle at Phillipines Sea.

Based on her construction, design and materials, to attempt to retrofit Soryu to meet RN or USN DC standards would be huge, time consuming project that would severely cramp operational realities, especially if Soryu was the sole survivor of the Midway Four. Makes me wonder if the IJN would even waste their time. In historical fact, the Japanese never raised the DC capability of their carriers to a RN or USN standard, both in terms of design and machinery or, just as importantly, overall personnel training. "Significantly improved" is subjective. Just about any improvement to Soryu's DC capability would be "significant."

Given also that the Brit Carriers could operate in weather conditions that the other nationalities could not, and that she was equipped and her air group trained to operate at night, ther is really no issue for me....the illustrious wins hands down.....in a fight under the right conditions, she would make a meal out of either of the other two.

I was not aware that either the Japanese or the Americans kept their carriers in port when threatened by foul weather. Learn something new every day. Your last sentence, though, is telling ". . . under the right conditions . . ." which means, of course, that any other conditions might just preclude the possibility of success. I'd suggest, from your own phrasing, that the suite of conditions under which a Yorktown carrier might typically expect success in an unlikely engagement with an Illustrious might have a trifle more options to it than the suite possessed by an Illustrious.

In 1940 her Fulmars and Swordfish, operating at night, or in the soupy conditions of the North Atlantic are going to outclass the F2as, the TBDs and the Vindicators then available to the USN by a wide margin. In 1941 and '42, the US Carrier achieves a notable superiority because of the wing folding SBDs, Avengers and Wildcats she was carrying. In 1943, the advantage swings slightly back in favour of the Brit carrier, because of her Corsairs that she now has embarked

Their only advantage is at night and that only works when you know where the enemy is, like a nice snug Italian harbor. Night searches are a whole different game. You are aware, are you not, that night operations from US carriers were not all that unusual during the same time period? For both the RN and the USN night operations were an operational capability, sort of a "we can do this" as opposed to "this is the way we prefer to do business." Also SBDs did not have folding wings and, with the exception of the XF4F-4, folding winged F4F's did not reach the fleet until early May 1942. The RN had F4Fs in action long before the USN (G-36A's from the French Navy order which became Martlet I's)and their first load of F4Fs with folding wings (F4F-4B/Martlet IV's) left Norfolk aboard (well, what do you know?) HMS Illustrious on 12 December 1941. Illustrious had been in the Norfolk Navy Yard for the previous eleven months recuperating from various indignities inflicted by enemy bombs, which impacted in the daytime.

Any advantage you might perceive in an Illustrious air group operating F4Us, and in summer of 1945 we're talking about 1830 Squadron (LCDR(A) A M Tritton, DSC +2 Bars RNVR) and 1833 Squadron (LCDR(A) N S Hansen, DSC, RNVR), together amassing about 36 F4U's, might be somewhat optimistic. Against a typical contemporary USN carrier, those 36 would have to contend, discounting the strike TBM's and SB2C's, and depending on which US carrier, some 73 F6F-5's, such as VF-87(LCDR C E Ingalls, Jr) and VBF-87 (CDR P W Maxwell), USS Ticonderoga; or a mix of 32 FG-1D's and 18 F4U-1C's (not to mention the air group night fighter section of 6 F6F-5N or the photo section of 2 F6F-5P's), such as VF-85 (LCDR W W Ford) and VBF-85 (LCDR S B Strong), USS Shangri La; or a mix of 36 F6F-5's and 37 FG-1D's, such as VF-88 (LCDR R G Crommelin) and VBF-88 (LCDR J E Hart), USS Yorktown. Yup, I'd say that was a little optimistic.

Regards,

Rich

 

[syscom3]

As usual, Leonard has a ton of good stuff.

 

[parsifal]

From the posts in reply to by Post number XX I can see that I need to explain a few terms I have used. "Operational Maximum" to me is not a theoretical total or a total that can be embarked when the carrier is being used in a non-battle situation. It is the maximum carried into battle , and when a carrier is used in more than one battle, one should look into the maximums carried into as many of those battles as one has reliable information for.

In the case of the british, however, I would draw a distinction for the period 1939-41. In that period British carriers routinely carried into battle far less aircraft than they were designed for, primarily because of the chronic pilot shortages that plagued the FAA at that time.

The other thing that needs to be noted is that the operational maximums for the Yorktown (the focus of this debate) were not the same as those for her two sisters. I am not sure why that is the case, but it just is.

Unfortunately I don't have sufficiently accurate enough information to apply the same rigour to the Illustrious. This has meant, unfortunately that I have had to group all the Illustrious class together to try and get meaningful figures on the operational maximum for that class of ship, rather than the particular ship we are looking at.

So, what were the operational maximums of the carriers in question at comparable times in the war??? Turning first Yorktown and her sisters, I found the following:

31-12-41 (just prior to the Wake operation)
Enterprise: 72, Yorktown: 69

April '32 (Raids to the Marshalls)
Enterprise: 81, Hornet: 65

May '42 (Coral Sea)
Yorktown: 71

June '42 (Midway)
Enterprise: 78, Yorktown: 75, Hornet: 79

August '42 (Watchtower)
Enterprise: 84

October '42 (Santa Cruz)
Enterprise: 84, Hornet: 87

November 1942 (Rennell Is)
Enterprise: 78

June 44 (Saipan)
Enterprise: 69

Average (Class): 76.3
Average (Yorktown): 71.7

Illustrious CAG (prior to selected operations

Aug-40: 30 a/c
Nov-40: 39 a/c
Nov-42: 45 a/c
Aug-45: 54 a/c

Selected Illustrious Class CAGs

April '42:
Indomitable: 45
Formidable: 38

11/42 (Torch)
Formidable: 42, Victorious: 47

January "44 (raids on Tirpitz)
Victorious: 48

Average (Class): 43.2
Average (Ilustrious): 42

Now, looking at the damage needed to sink each of the classes, well none of the Illustrious class were ever sunk, although the name ship herself came close to spoiling that record, in January 1941, when she suffered no less than 6 hits, (5 x 1000 lbs, and one 500 lbs), a stuka crashing into her upper deck, and a further hit later that day. Whilst in port undergoing emergency repairs she suffered a further 3 hits. The damage to her was extensive, and included , in summary


1. Hit and destroyed the starboard S2 pom-pom, killing most of the crew;
2. Penetrated the forward end of the flight deck and passed overboard, exploding above the water. Caused extensive splinter damage to several compartments and started a fire in one;
3. Exploded in the after lift-well, 10-20 ft below the flight deck, severely damaging the lift and destroying a Fulmar on the lift;
4. Penetrated the armored flight deck and exploded just above the hangar deck, damaging the forward lift and surrounding structure, and starting a fire on the hangar deck. Several aircraft in the hangar deck were destroyed;
5. Hit the after end of the after lift, adding to the damage of bomb #3;
6. Penetrated a pom-pom platform, passed through the shipand went overboard without detonating. A fire was started on two mess decks.
7. Also hit the after lift, completing its destruction.
8. A near-miss off the starboard side caused slight structural damage and minor flooding.


Casualties amounted to 126 dead in that attack. The ship had been attacked by a force of about 50 Stukas, which in the following days expanded to an average daily attack of over 70 aircraft

But it is worth noting that despite this terrible pounding the Ilustrious never lost power, and remained underway at all times. At no time was she forced to hoist an NUC (not under command) signal. Within 14 days she made good her escape, able to make more than 20 knots in her run out of the central basin


In comparison, the Yorktown suffered damage sufficient to knock her out of action from three 500 lb hits and 2 x 18 inch aerial torpedoes.

The following is a brief summary of the hits that led to her loss

Despite the barrage, though, three Vals scored hits with 250 kg bombs. The bombs hit just abaft number two elevator on the starboard side, exploding on contact and blasting a hole about 10 feet square in the flight deck. Splinters from the exploding bomb decimated the crews of the two 1.1-inch gun mounts aft of the island and on the flight deck below. Fragments piercing the flight deck hit three planes on the hangar deck, starting fires. One of the aircraft, a Yorktown Dauntless, was fully fueled and carrying a 1,000-pound bomb. Prompt action by Lt. A. C. Emerson, the hangar deck officer, prevented a serious conflagration by releasing the sprinkler system and quickly extinguishing the fire.
The second bomb to hit the ship came from the port side, pierced the flight deck, and exploded in the lower part of the funnel. It ruptured the uptakes for three boilers, disabled two boilers themselves, and extinguished the fires in five boilers. Smoke and gases began filling the firerooms of six boilers. The men at number one boiler, however, remained at their post despite their danger and discomfort and kept its fire going, maintaining enough steam pressure to allow the auxiliary steam systems to function.
A third bomb hit the carrier from the starboard side pierced the side of number one elevator and exploded on the fourth deck, starting a persistent fire in the rag storage space, adjacent to the forward gasoline stowage and the magazines. The prior precaution of smothering the gasoline system with CO2, undoubtedly prevented the gasoline's igniting.
While the ship recovered from the damage inflicted by the dive-bombing attack, her speed dropped to six knots; and then, at 1440, about 20 minutes after the bomb hit that had shut down most of the boilers, Yorktown slowed to a stop, dead in the water.
At about 1540, Yorktown prepared to get underway again; and, at 1550, the engine room force reported that they were ready to make 20 knots or better. The ship was not yet out of the fight. \
Simultaneously, with the fires controlled sufficiently to warrant the resumption of fueling operations, Yorktown began fueling the gasoline tanks of the fighters then on deck. Fueling had just commenced when the ship's radar picked up an incoming air group at a distance of 33 miles away. While the ship prepared for battle — again smothering gasoline systems and stopping the fueling of the planes on her flight deck — she vectored four of the six fighters of the CAP in the air to intercept the incoming raiders. Of the 10 fighters on board, eight had as much as 23 gallons of fuel in their tanks. They accordingly were launched as the remaining pair of fighters of the CAP headed out to intercept the Japanese planes.
At 1600, Yorktown churned forward, making 20 knots. The fighters she had launched and vectored out to intercept had meanwhile made contact, Yorktown received reports that the planes were Kates. The Wildcats downed at least three of the attacking torpedo planes, but the rest began their approach in the teeth of a heavy antiaircraft barrage from the carrier and her escorts.
Yorktown maneuvered radically, avoiding at least two torpedoes before two "fish" tore into her port side within minutes of each other. The first hit at 1620. The carrier had been mortally wounded; she lost power and went dead in the water with a jammed rudder and an increasing list to port.
As the list progressed, Cmdr. C. E. Aldrich, the damage control officer, reported from central station that, without power, controlling the flooding looked impossible. The engineering officer, Lt. Cmdr. J. F. Delaney, soon reported that all fires were out; all power was lost; and. worse yet, it was impossible to correct the list. Faced with that situation, Capt. Buckmaster ordered Aldrich, Delaney, and their men to secure and lay up on deck to put on life jackets.
The list, meanwhile, continued to increase. When it reached 26 degrees, Buckmaster and Aldrich agreed that the ship's capsizing was only a matter of minutes. "In order to save as many of the ship's company as possible," the captain wrote later, he "ordered the ship to be abandoned."

Interestingly, the amount of damage needed to immobilize (and eventually cause the loos) of Hornet, was remarkably similar to the amount of damage needed to do the same to Yorktown. Hornet was immobilized by three bomb hits, two torpedo hits, and a Kate crashed into the superstructure

In my opinion the damage firepower needed to knock the Yorktown out was about one third to half that expended on the Illustrious. In terms of the ordinance weight, the Illustrious had absorbed about 8500 lbs of explosive, whilst Yorktown and Hornet had each absorbed about 2200 lbs of explosives. Unquestionably the torpedoes had the potential to cause greater levels of damage than the bombs falling on the Illustrious, but still, the weight of bombs is still a rough, but still valuable measure of the amount of damage each ship could absorb

 

[renrich]

Bombs let air in, torpedoes let water in. Torpedoes were far more damaging to ships in WW2. Enterprise was hit often by bombs and always survived.

 

[Glider]

I have some information on the Aircraft carried by the Illustrious at various times during the war if that will help.

Sept 1940 15 Fulmars and 18 Swordfish
May 1942 20 Wildcats and 20 Swordfish
Sept 1943 26 Wildcats, 10 Seafires and 10 Barracudas
May 1944 28 Corsairs and 21 Avengers
March 1945 36 Corsairs and 16 Avengers

 

[Amsel]

Torpedos could not be protected against.

 

[parsifal]

As a rough generalization, bombs were more effective at closing down flight operations, and were more conducive at propagating fire, however topredoes were more dangerous to the propulsion and flotation systems of a ship. There were effective defences against both forms of attack....

Wiki has the following article with respect to anti-torpedo bulges....

Essentially, the bulge is a lateral compartment at the waterline level that is isolated from the ship's internal volume. It is part air-filled, and part free-flooding. In theory, a torpedo strike will rupture and flood the air-filled component of the bulge and the water-filled part will dissipate the shock and absorb explosive fragments, leaving the ship's main hull structurally intact. Transverse bulkheads within the bulge limit flooding throughout the entirety of the structure.

The bulge was developed by the British Director of Naval Construction, Eustace Tennyson-D'Eyncourt, who had four old Edgar-class protected cruisers so fitted in 1914. These ships were used for shore bombardment duties, and so were exposed to inshore submarine and torpedo boat attack. Grafton was torpedoed in 1917, and apart from a few minor splinter holes, the damage was confined to the bulge and the ship safely made port. Edgar was hit in 1918, this time damage to the elderly hull was confined to dented plating. The Royal Navy had all new construction fitted with bulges from 1914, beginning with the Revenge-class battleships. Older ships also had bulges incorporated during refits. The Royal Navy had its large monitors fitted with enormous bulges. This was fortuitous for Terror, which survived 3 torpedoes striking the hull forwards and her sister Erebus, which survived a direct hit from a remotely-controlled explosive motor boat that ripped off 50 feet (15.25 m) of her bulge.

Later designs of bulges incorporated various combinations of air and water filled compartments and packing of wood and sealed tubes. As bulges increased a ship's beam, they caused a reduction in speed, which is a function of the length to beam ratio. Therefore, various combinations of narrow and internal bulges appeared throughout the 1920s and into the 1930s. The bulge had disappeared from construction in the 1930s, being replaced by internal arrangements of compartments with a similar function

Anti-torpedo bulges were still added as retrofits to older ships, such as HMS Renown and USS Enterprise

As a rough generalization, British carrier design was thought to be ahead of the USN in terms of its underwater protection, as well as the extent of its deck protection. However, it has to be conceded that the Ark Royal came up short when it came to the crunch. Whilst her loss can be attributed somewhat to poor damage control of the particular event . As the sole modern carrier in more or less continous service from the very beginning of the war, she had never the opportunity to rectify some of the more glaring design faults that were clearly evident, even before her loss. As part of a very modest pre-war re-arrmament program, her designers had taken the shortcut of routing the boiler room uptakes directly beneath the lower hangar, and this proved to be a very vulnerable aspect, as the flooding of the port boiler room generated a modest list of only 19 degrees, but this was sufficient to block the furnace emissions, with a resultant fire contributing greatly to her eventual loss. If the uptakes had been routed further up in the hull, it would have increased the angle of heel needed to close off the funnel exhausts, but in turn would have restricted the aircraft complement she could carry on such a restricted displacement. Another option would have been to armour the funnel uptakes, but this would have increased her displacement above 22000 tons, which for political reasons was unnacceptable to the pacifist pre-war British governments.

But whilst at least these passive defence measures were considered, and ultiimately quite successfully tackled in British carrier design, in the prewar US carriers it was not well tackled, with the result that US Carriers were not well protected, as built, with passive design features. Their internal anti-toprepdo protection was quite weak, and this showed in their relative inability to withstand much punishment, particularly from torpedoes. Small wonder that some of you are saying that there was no effective torpedo defences. In the US experience this was quite true until the arrival of the Essex class. As previously pointed out by a number of the Americans in this forum, the US carriers relied primarily on their ability to carry large numbers of aircraft. That is not to say thet they did not incorporate some good defensive features, but the Enterprise class, like the Ark Royal were major exercises in design compromise, and for the Americans a great deal was sacrificed so as to get as many planes to sea as possible...not the one hundred as is often claimed for them, but operationally more about the 70-80 number, but still an impressive number

 

[parsifal]

Ther is one other variable to consider in this debate....the displacements of the ships being compared. In the pre-war treaty driven navies, the displacement of the ship was paramount....basically the heavier the ship, the less numbers of that ship were going to be available.

The Illustrious class were the heaviest of the three, using deep load displacements as a gude (I cannot rememeber if the treaties used deep load or standard). She had a displacement of 29000 tons.

The Yorktowns were next, at 27000 tons

Ther was some variation between the Soryu and the Hiryu, but the Soryu was lightweight, she had a deep load displacement of only 18500 tons.

This means that for every three Yorktowns, you could have 4.5 Soryus (roughly). Using this favourite argument of aircraft numbers being the all important criteria, and based on operational maximums of 76 (for the Yorktowns) versus 63 (for the Soryus, the Soryus represent the better value....the tonnages spent on the Yorktowns allowed 228 aircraft to be taken to sea, whilst the erquivalent tonnage for the Japanese carriers allowed 284 aircraft to be taken to sea.

Of course the Soryus were more vulnerable, than the Yorktowns, but just how vulnerable becomes a little more problematic, if the Japanese can field 50% more hulls on the same displacement

 

[vikingBerserker]

With regards to the Yorktown I think you left out the final blows being 2 torpedoes from the I-168 (a 3rd had blown the USS Hammann (DD-412) in half).

Also, you have to keep in mind that at Coral Sea she had been hit by a Val and had been temprarily repaired in 4 days before Midway.

 

[parsifal]

With regards to the Yorktown I think you left out the final blows being 2 torpedoes from the I-168 (a 3rd had blown the USS Hammann (DD-412) in half).

Also, you have to keep in mind that at Coral Sea she had been hit by a Val and had been temprarily repaired in 4 days before Midway.

All true, but the ship was totally knocked out by the airstrikes. She was dead in the water and no lnger contributing to the battle. The sub torpedo from I-168 did the actual sinking, By comparison the Illustrious was never removed as a functional unit of the fleet throughout her ordeal.

The object of the game, in the first instance is to remove the threat, which, if that can be achieved without actually sinking the hull is all the better.

Remember also that Hoirnet suffered nearly identical levels of damage when she was lost

 

[R Leonard]

All true, but the ship was totally knocked out by the airstrikes. She was dead in the water and no lnger contributing to the battle.

Nope, you need to read up a little more on Midway.

 

[parsifal]

Nope, you need to read up a little more on Midway.

Okay, are you suggesting the ship could undertake independant action of any kind after the second strike by the kates hit her????

 

[R Leonard]

From the posts in reply to by Post number XX I can see that I need to explain a few terms I have used. "Operational Maximum" to me is not a theoretical total or a total that can be embarked when the carrier is being used in a non-battle situation. It is the maximum carried into battle , and when a carrier is used in more than one battle, one should look into the maximums carried into as many of those battles as one has reliable information for.

You must have missed the source of the aircraft complements noted in my last, to wit, the actual USN aircraft location reports which were submitted to BuAer on a weekly basis noting the number of aircraft present in a given squadron. Not theoretical, drawn from the actual number of aircraft present in squadrons as reported through channels to BuAer.

. . . less aircraft than they were designed for, primarily because of the chronic pilot shortages that plagued the FAA at that time.

I have never heard of this explanation for smaller complements aboard RN fleet carriers. Do you have some official source which explains this?

. . . operational maximums for the Yorktown . . . were not the same as those for her two sisters. I am not sure why that is the case, but it just is.

Yorktown was lower due to the aircraft carried, as I pointed out in my previous. F4F-3's and SBD's did not have folding wings and, therefore, took up more room. Yorktown did not embark folding wing F4F-4's until 28 May 42 as she deployed for Midway. One might note that the number of fighters aboard Yorktown jumped from the VF-42 F4F-3 complement of 18 up to the VF-3 complement of 27.

I find it interesting that you want to explain smaller RN air groups by a lack of pilots/crew when you fail to recognize the effects of an overall USN shortage of TBD's in the Pacific limiting the number that could be assigned to a given carrier. The three Yorktown class carriers were, in fact, rated for 18 TBD's.

Unfortunately . . . the particular ship we are looking at.

Which is exactly why I used Enterprise data as it encompassed the entire war rather than just the first 6 months.

So, what were the operational maximums of the carriers in question at comparable times in the war??? Turning first Yorktown and her sisters, I found the following:

31-12-41 (just prior to the Wake operation)
Enterprise: 72, Yorktown: 69

Wake operation was in 24 February 1942. On 31 December 42, Yorktown had arrived at San Diego, Hornet was at Norfolk, and Enterprise was at sea. Your count is a little off:

Yorktown
VT-5 - 14 TBD-1
VS-5 - 19 SBD-3
VS-5 - 2 SNJ-3
VF-42 - 18 F4F-3
VB-5 - 19 SBD-3
CYAG - 1 SBD-3
CV-5 - 2 JRF-5
CV-5 - 1 SOC-1
Subtotal 71 combat aircraft
Total 76 aircraft

Enterprise
VT-6 - 1 SNJ-3
VT-6 - 18 TBD-1
VS-6 - 10 SBD-2
VS-6 - 8 SBD-3
VF-6 - 3 F4F-3
VF-6 - 17 F4F-3A
VB-6 - 18 SBD-2
CV-6 - 2 JRF-2
CV-6 - 2 SBD-2
CV-6 - 2 SBD-3
CV-6 - 2 SOC-3
CV-6 - 4 TBD-1
CEAG - 1 SBD-2
Subtotal 83 combat aircraft
Total 88 aircraft

Hornet
VT-8 - 7 SNB-1
VT-8 - 8 TBD-1
VS-8 - 20 SBC-4
VF-8 - 19 F4F-3
VF-8 - 2 F4F-3A
VF-8 - 2 SNJ-3
VB-8 - 19 SBC-4
CV-8 - 2 JRF-5
CV-8 - 2 OS2U-2
Subtotal 68 combat aircraft
Total 81 aircraft

April '32 (Raids to the Marshalls)
Enterprise: 81, Hornet: 65

Marshalls-Gilberts raids were 1-2 February 1942, not in April. Hornet was no where near the action. These raids were carried out by Enterprise and Yorktown.

YAG had lost 3 VF-42 F4F-3's in take off accidents between 8 Jan 42 and 14 Jan 42. The ship was at sea, on her way to Samoa. There was no where to get replacement aircraft. So, on the eve of the 1 Feb 42 Jaluit/Makin strikes, VF-42 had but 15 aircraft and that the YAG total combat complement available was 68 out of the 71 it had on 31 December. It did not mean that 15 F4F-3's were all that could be operated, nor that 68 was the maximum operational complement. It does not mean, no matter how much you want it to, that 68 aircraft was the maximum Yorktown could carry into battle, it only means this was the number on hand.

Enterprise started out with on 31 Dec 41 with 83 combat aircraft. That day VF-6 lost b/n 3907 in a landing accident. The ship arrived at Pearl Harbor on 7 Jan 42 and the lost F4F-3 was replaced by a pool spare so this did not result in a complement change; so Enterprise and the EAG left for the north Marshalls on 11 Jan 42 with a full combat complement of 83 aircraft. On 16 Jan, an SBD was lost in a landing accident and a TBD-1 disappeared altogether. This reduced available, not rated, aircraft to your noted 81.

May '42 (Coral Sea)
Yorktown: 71

I count 69 VF/VSB/VT aboard. VF-42 lost two F4F-3's on 4 May 42 and VT-5 lost a TBD-1, so that does not quite explain the difference. In any case, availability does not always equal routine operating capacity and does not mean that capacity is lowered.

June '42 (Midway)
Enterprise: 78, Yorktown: 75, Hornet: 79

Enterprise lost one TBD, b/n 370, in a landing accident on 28 May, reducing its available TBD strength to 14. VF-6 had 27 F4F-4's; VB-6, 19 SBD's (1 GC); and VS-6, 18 SBD; giving us, indeed, a total on the eve of the battle of 78, but they started with 79. VT-6 had previously lost TBD's b/n's 0335 (see above) and, later, 0274, in the Marshall's strikes; neither had been replaced, so with 18 on hand on 31 Dec 41 and these three losses, none of which were replaced as there was naught with which to replace them, that should have left us with 15 TBD's, but alas, it appears as one seems to have escaped my notice as there were but 14 left after Lindsey's crash. Again, though, your subtraction out of losses does not give an accurate picture of routine operating complements.

Yorktown's VT-3 had 16 TBD's on hand for the deployment, one, b/n 1517, was a dud and was left behind at Pearl; there were no spares not already earmarked for other duty to replace it (same problem VT-6 had). That does not equate to the ship not being able to operate 16 vs 15 TBD's, especially when 18 was considered a full complement. Generously not counting that one missing TBD into account, the YAG had 79 aircraft aboard on the eve of the battle, 27 F4F-4 (25 operational), 37 SBD (18 VB-5, 18 VB-3, 1 GC), and 15 TBD's. VT-3's two early TBD operating losses on 8 Jan 42 and 10 Jan 42 had not been replaced. So, counting the 15 TBD's aboard Yorktown, plus the one dud left at Pearl, plus the two lost operationally in January and never replaced, VT-3's routine operating complement was 18. Had all 18 been available, they would have been aboard Yorktown.

HAG had a total of 80 aircraft assigned on the eve of the Midway deployment. VT-8 lost a TBD in a landing crash at Pearl in the days before departure, reducing available TBD's to 15. VF-8 had 27 F4F-4's; VB-8, 9 (including the GC's); VS-8 started with 18 SBD's, 1 SBD was a dud and left behind at Pearl Harbor and another was lost operationally on 29 May. This left the HAG with 77 from a routine operating complement of 81.

August '42 (Watchtower)
Enterprise: 84

I see the BuAer location returns as Enterprise with 88. Hornet complement in the same report is 87.

It's tedious to go through all these instances where you seem to confuse availability with rated and routine operating complements.

Snipping the remaining actions you listed (And, gee, if you really want me to go through them, I will, but I'm searching for a little brevity here. I have a life, and a job, and family responsibilities and really cannot devote hours and hours to this stuff. I have already provided in my previous posts the average returns from the aircraft location reports; followers of the thread can note the differences between your numbers and mine and draw their own conclusions.)

Let us move on . . .

Illustrious CAG (prior to selected operations

I have no problem with your Illustrious complement numbers, but I wonder if you give them the same availability versus routine complement short shrift. Not having any data to challenge same, I believe you.

I am going to snip portions of your post regarding how tough the Illustrious was versus Yorktown class complete with recitations of damaged inflicted on each where you point out that the Illustrious was not sunk. Well, good. How many torpedoes did Illustrious take?

My point would be that no US fleet carrier was lost to bombs, nor Kamikazes, alone. That the US fleet carriers that were lost over the course of the war, Lexington, Yorktown, Hornet, and, being generous, Wasp, were all torpedoed. So to trot out Illustrious with her armored deck and claim some sort of superiority by comparison to non-armored deck ships lost to torpedoes is IMO somewhat disingenuous.

How about this, Illustrious was under repair at Norfolk Navy Yard for eleven months after her adventures in the Mediterranean. Eleven months. And is there a guess on how long the average USN CV spent in the yard after being hit by a bomb(s) or Kamikaze(s)? Looks like about 52 days on average, slightly less than 2 months and that includes almost a year for USS Franklin.

If you want to sink a ship, letting water in is much more efficient than letting daylight in. You compare apples and oranges.

Regards,

Rich

 

[parsifal]

If you want to sink a ship, letting water in is much more efficient than letting daylight in. You compare apples and oranges.

[/QUOTE]

Hi Rich

Thanks for the comprhensive reply, much appreciated. In regards to this point, would you not agree that the greatest single danger to a carrier was the risk of fire. And while torpedoes can cause fires, I think bombs are far more likley to cause a fire. Moreover, if the ship is provided with adequate torpedo protection a torpedo is going to let in a relatively small amount of water. This would have been the case for the Ark Royal, if not for her inherent design flaw that failed her in the end. A Japanese air launched torpedo only has 331 lbs of warhead I might add, whereas a 1000lb bomb actually1100 lbs if german) has explosive charge in excess of 650 lbs)

I did rather get my operations dates mixed up for which I am embarrased about. 31-12-41 was a strength date given by Brown and carries the note that this was the strength before the cancelled opersation to Wake....it carries the further note that Yorktown arrived 6th Jan....I dont know what I was thiniking when I wrote that up.....

Talking about losses is missing the main object of a carrier strike. It is not, in fact, the primary aim of the airstrike to sink the carrier, although that is admittedly a big bonus if it can be achieved. The aim is primarily to prevent it from operating aircraft, in the first instance, and secondly to immobilize it. Bombs are far more potent and capable at disabling the flight deck of a carrier. and hence removing it as a threat.

Moreover, I think you need to consider that in the main the US carriers were being hit with 250kg bombs, being the main armament of the Val. The British Carriers were being mostly hit by 1100 lbs capacity, which I can assure you are far more powerful pieces of ordinance. Your assessment is akin to saying an 8" shell is equival;ent to a 16" shell in terms of its damage capabilities.

Torpedoes tend to work on the hull integrity and the propulsion systems, whilst bombs work on the flight deck and and superstructure. Bombs can do a lot of damage if they penetrate the armoured box (sometimes referred to as the citadel). As far as I know this did not happen to any US carrier, but I think this was because the US defences were designed to withstand a 500lb impact, but not a 1000 lb bomb.

Your reference to the long repair times for the Illustrious is indeed a major flaw in the armoured deck concept....once the bombs pentrated the armoured deck the amount of damage went up exponentially. It was a bit like putting a stick of dynamite inside a sardine tin.....not pretty.

My figures for operational aircraft were based on ajust a quick look at David Browns "Carrier Operations of wwii".

I finished up not drawing any distinctions about aircraft shortages in 1940 for the RN. You are right, that would probably just skew the dataset. However I can assure you that the RN throughout 1940 struggled with an acute numbers shortage. For the whole of 1940, they received the grand total of just 16 pilots, which is no way to run a war, surely you would agree.

If you adopt my rough method for determining the amount of damage a ship can absorb before being renedered inoperable (or you can simply look at how much it took to sink a ship), I think you are going to find an intersting consistency in the tonnage of explosives needed to destroy a target.

Anyway, dont let me keep you from your more important things to do like your family and the like.....

 

[Glider]

My point would be that no US fleet carrier was lost to bombs, nor Kamikazes, alone. That the US fleet carriers that were lost over the course of the war, Lexington, Yorktown, Hornet, and, being generous, Wasp, were all torpedoed. So to trot out Illustrious with her armored deck and claim some sort of superiority by comparison to non-armored deck ships lost to torpedoes is IMO somewhat disingenuous.

How about this, Illustrious was under repair at Norfolk Navy Yard for eleven months after her adventures in the Mediterranean. Eleven months. And is there a guess on how long the average USN CV spent in the yard after being hit by a bomb(s) or Kamikaze(s)? Looks like about 52 days on average, slightly less than 2 months and that includes almost a year for USS Franklin.

If you want to sink a ship, letting water in is much more efficient than letting daylight in. You compare apples and oranges.

Regards,

Rich

The comment about torpedo's is valid as the Illustrious was not hit by any however the comment about repair times is a little unfair. No other carrier in the world would have taken the pounding that the Illustrious received that is certain, so its only to be expected that she would take some time to repair. However there are plusses and minus's in anything and that goes for the armoured box on the Illlustrious.

The Minus side
- If you have a major fire inside the hanger Box then the hanger acts like a pressure cooker increasing the temperatures and structural buckling

The Plus side
- You are far less likely to have a fire in the hanger as the armoured deck reduces the chances of this happening.
- The fires are more likely to be contained within the Hanger due to the extra rigidity/strength of the hanger
- The US carrriers were almost certain to have to spend time in dock after a hit on the deck. In similar circumstances a similar hit on an armoured deck will normally cause a dent in the flight deck easily fixed with quick drying cement. A simple easy and effective repair.
So yes when the damaged Illustrious did have to spend longer in dock but the chances of her having to go in for repair are less