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.
The number of aircraft the Yorktown carried into Midway was 75
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
About 50% of the USN carriers maintained a permanent deck park. The idea was thought up in the early 1930's.
So in the end, the operational maximums of the three classes are: Yorktown 72, Soryu 63, and Illustrious 52.
Yorktown's max was 75 that could be maintained by a full complement of AV fuel as well as armaments, while the Illustrious was fitted to maintain 40 aircraft. Due to the obselete armored carrier idea that traded deck space, range and maintance capabilities for an armored deck.
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
The interesting thing about the open hanger system is that it was designed with naval aviation in mind. Something seriously lacking in the RN when the Illustrious was built was a mind toward aviation being the new weapon of naval war. The idea was caught before the war started thankfully and they did not build another CV like it. The Midway class was laid down with an open hanger so the WWII piston aircraft can be warmed up ready to depart at all times,which may be dangerous defesively but actually increases the offensive capabilities of the carrier. That is what the USN wanted, an aviation minded fleet. The trade off of armor for strike capability plagued the Illustrious.
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.
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.
Actually the USN did develop night carrier operations.
The Illustrious would find it very difficult to make meal out of a USN CV because it was designed as awarship and not a strike carrier. The USN naval air operations were top of the line and even the seaminded RN had to adopt them. If the Illustrious was at Midway then I fear that the Japanese might have won that battle. 75 sorties versus 40 is quite a big stretch, especially considering the USN used divebombers which the RN did not develop in time for some reason. The USN used divebombers as scouts and if an enemy carrier is spotted then they could plant their bombs into the enemy and rtb while the carrier still had a large force for more strikes to finish the job. The large flight deck, three fast elevators, as well as the open hanger design would ensure that a larger force would be in the air faster, and thats what mattered in carrier to carrier operations.
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
