The Case For (Or Against) Armoured Flight Decks in WW2

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Re: The Case For (Or Against) Armoured Flight Decks in WW2

Post by alecsandros » Tue Dec 09, 2014 6:20 am

dunmunro wrote:
alecsandros wrote:@Duncan,
Enterprise and Essex class carried up to 100 aircraft.
Implacablee carried around 80.

The USN carriers had lomger range in exchange for poorer protection
AA systems were comparable, at least in size.
Enterprise class never operated with 100 aircraft. Typical 1942 mix was ~72 plus spares and typical mix after her 1943 refit was ~60 plus spares. AA armament as designed was 8 x 5"/38 (open mounts), 16 x 1.1" and 24 x .5". Illustrious/Implacable design armament was 16 x 4.5in (twin turrets), 48 x 40mm pom-pom and 32 x .5". At the end of the war both carriers had much increased automatic armament, but to do so Enterprise had to be widened via a blister (bulge) which considerably increased her displacement. Enterprise as designed had a very weak AA armament.

Range was never an issue with RN carriers but the first 3 did have insufficient avgas capacity when their airgroups were enlarged via a deck park.
... Enterprise carried up to 100 aircraft (IIRC during the Guadalcanal landings 6-7 Aug), and had a longer range than the RN counterparts, meaning it could operate at longer distances without refueling :)

AA guns for Enterprise at Santa Cruz was 16x40mm, 4x28mm, 44x20mm and by Oct 1943 it was 40x40mm Bofors and 50 x 20mm Oerlikon.

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Re: The Case For (Or Against) Armoured Flight Decks in WW2

Post by aurora » Tue Dec 09, 2014 9:21 am

Steve Crandell wrote:Which Essex class CVs were sunk by bombs?

Which British CVs were sunk by torpedoes?
Steve-There were no Essex Class carriers sunk by enemy weapons -only rwo severely damaged as stated.HMS Courageous,Ark Royal and Eagle were sunk by torpedoes
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Re: The Case For (Or Against) Armoured Flight Decks in WW2

Post by aurora » Tue Dec 09, 2014 9:39 am

Quote alecsandros

"Enterprise carried up to 100 aircraft (IIRC during the Guadalcanal landings 6-7 Aug), and had a longer range than the RN counterparts, meaning it could operate at longer distances without refueling :)

AA guns for Enterprise at Santa Cruz was 16x40mm, 4x28mm, 44x20mm and by Oct 1943 it was 40x40mm Bofors and 50 x 20mm Oerlikon".

Hereunder details of changes to Enterprise's weaponry during WW2-your October 1943 figures are correct but none of my other figures corresond to your Santa Cruz figure

Armament:
As built:
8 × single 5 in/38 cal guns
4 × quad 1.1 in/75 cal guns
24 × .50 caliber machine guns

From April 1942:
8 × 5 in/38 cal
4 × quad 1.1 in/75 cal
30 × 20 mm Oerlikon cannons

From mid-June 1942 to mid-September 1942:
8 × 5 in/38 cal
5 × quad 1.1 in/75 cal
32 × 20 mm Oerlikons

From mid-September 1942:

8 × 5 in/38 cal
4 × quad 40 mm Bofors guns
1 × quad 1.1 in/75 cal
44 × 20 mm Oerlikons(46 from 11/42)

From October 1943:
8 × 5 in/38 cal
40 × 40 mm Bofors (8×2, 6×4)
50 × 20 mm Oerlikon

From September 1945:
8 × 5 in/38 cal
54 × 40 mm Bofors (5×2, 11×4)
32 × 20 mm Oerlikons (16×2)
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Re: The Case For (Or Against) Armoured Flight Decks in WW2

Post by aurora » Tue Dec 09, 2014 11:25 am

To return to original premise-armoured flight decks-the good and bad aspects of them

British carriers were sometimes criticised for having too small airgroups in European operations. This is because the Pacific practice of having 50% of aircraft in permanent deckparks could not be considered in European waters. Once British carriers arrived in the Pacific they too had 50% deck parks, for example HMS Indomitable, with a hangar area 85% of that of USS Yorktown, operated 72 aircraft in the Pacific compared to the Yorktown’s 80 odd. Which means that British carriers could have operated bigger air groups in Europe, IF and only IF anyone had considered that wise. The difference being that if a bomb hit a deckpark, the planes tended to catch fire. In British carriers, even with Pacific style deck parks, that tended to be the end of the problem, and the other planes below deck could also be used to continue operations- after some concrete had been poured on any dents in the deck.

In American or Japanese carriers, burning deckparks usually led to exploding ships, or at the very least months in the dockyards. Certainly continued air operations were not very common (though it did happen twice), which just shows that anything is possible.
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Re: The Case For (Or Against) Armoured Flight Decks in WW2

Post by alecsandros » Tue Dec 09, 2014 11:52 am

aurora wrote:
Armament:


From mid-September 1942:

8 × 5 in/38 cal
4 × quad 40 mm Bofors guns
1 × quad 1.1 in/75 cal
44 × 20 mm Oerlikons(46 from 11/42)
4 x quad 40 = 16 x 40mm Bofors
1 x quad 1.1 = 4 x 28mm

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Re: The Case For (Or Against) Armoured Flight Decks in WW2

Post by dunmunro » Tue Dec 09, 2014 11:59 am

alecsandros wrote:
dunmunro wrote:
alecsandros wrote:@Duncan,
Enterprise and Essex class carried up to 100 aircraft.
Implacablee carried around 80.

The USN carriers had lomger range in exchange for poorer protection
AA systems were comparable, at least in size.
Enterprise class never operated with 100 aircraft. Typical 1942 mix was ~72 plus spares and typical mix after her 1943 refit was ~60 plus spares. AA armament as designed was 8 x 5"/38 (open mounts), 16 x 1.1" and 24 x .5". Illustrious/Implacable design armament was 16 x 4.5in (twin turrets), 48 x 40mm pom-pom and 32 x .5". At the end of the war both carriers had much increased automatic armament, but to do so Enterprise had to be widened via a blister (bulge) which considerably increased her displacement. Enterprise as designed had a very weak AA armament.

Range was never an issue with RN carriers but the first 3 did have insufficient avgas capacity when their airgroups were enlarged via a deck park.
... Enterprise carried up to 100 aircraft (IIRC during the Guadalcanal landings 6-7 Aug), and had a longer range than the RN counterparts, meaning it could operate at longer distances without refueling :)

AA guns for Enterprise at Santa Cruz was 16x40mm, 4x28mm, 44x20mm and by Oct 1943 it was 40x40mm Bofors and 50 x 20mm Oerlikon.
Enterprise was carrying 90 aircraft enroute to Guadalcanal, but her operational airgroup was about 74-77, with the rest being spares or aircraft that were carried for delivery. At Eastern Solomons Enterprise had 74 operational aircraft with 80 embarked.

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Re: The Case For (Or Against) Armoured Flight Decks in WW2

Post by alecsandros » Tue Dec 09, 2014 12:15 pm

dunmunro wrote:

Enterprise was carrying 90 aircraft enroute to Guadalcanal, but her operational airgroup was about 74-77, with the rest being spares or aircraft that were carried for delivery. At Eastern Solomons Enterprise had 74 operational aircraft with 80 embarked.
.... I remember reading about ~ 98 planes embarked at the time of Guadalcanal, with about 80 operational in the hangars and deck park...
[take a look here: http://www.cv6.org/ship/big_e.htm "Aircraft Capacity 96 maximum: more typically 80-90 were on board"]

At Midway, Enterprise carried 79 planes, with no spares, AFAIK.

A fair comparison as far as historical time is concerned is to compare Enterprise/Yorktown with Illustrious, and Essex with Implacable.

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Re: The Case For (Or Against) Armoured Flight Decks in WW2

Post by aurora » Tue Dec 09, 2014 12:55 pm

alecsandros wrote:
dunmunro wrote:

Enterprise was carrying 90 aircraft enroute to Guadalcanal, but her operational airgroup was about 74-77, with the rest being spares or aircraft that were carried for delivery. At Eastern Solomons Enterprise had 74 operational aircraft with 80 embarked.
.... I remember reading about ~ 98 planes embarked at the time of Guadalcanal, with about 80 operational in the hangars and deck park...
[take a look here: http://www.cv6.org/ship/big_e.htm "Aircraft Capacity 96 maximum: more typically 80-90 were on board"]

At Midway, Enterprise carried 79 planes, with no spares, AFAIK.

A fair comparison as far as historical time is concerned is to compare Enterprise/Yorktown with Illustrious, and Essex with Implacable.


If you think that is the way forward alecsandros-then so be it-it is OK by me
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Re: The Case For (Or Against) Armoured Flight Decks in WW2

Post by aurora » Tue Dec 09, 2014 1:48 pm

HMS INDOMITABLE
Displacement: 23,000 tons standard,
29,730 tons loaded
Length: 230.0 metres (754.0 ft)
Beam: 29.2 metres (95.5 ft)
Draught: 8.8 metres (29.0 ft)

Propulsion: Parson geared steam turbines-six boilers,three shafts-111,000 shp
Speed: 30.5 knots (56 km/h)
Range: 11,000 nautical miles (20,000 km) at 14 knots (26 km/h)

Complement: 1,392
2,100 (later)

Armament:
16 × 4.5 inch AA
48 × 2 pounder AA
10 × 20mm AA

Armour=4 inch side, 1 inch hangar sides, 3 inch flight deck, 2 inch hangar decks

Aircraft carried:
1942: 22 Sea Hurricane, 12 Martlet and 16 Albacore
1943: 55 Seafire and Albacore
1945: 45 Hellcat and Avenger

USS ESSEX
Class & type: Essex-class aircraft carrier
Displacement: As built:
27,100 tons standard
36,380 tons full load
Length: As built:
820 feet (250 m) waterline
872 feet (266 m) overall
Beam: As built:
93 feet (28 m) waterline
147 feet 6 inches (45 m) overall
Draft: As built:
28 feet 5 inches (8.66 m) light
34 feet 2 inches (10.41 m) full load

Propulsion: As designed:
8 × boilers 565 psi (3,900 kPa) 850 °F (450 °C),4 × Westinghouse geared steam turbines-4 × shafts-150,000 shp (110 MW)
Speed: 33 knots (61 km/h)
Range: 20,000 nautical miles (37,000 km) at 15 knots (28 km/h)

Complement: As built:
2,600 officers and enlisted men
Armament: As built:
4 × twin 5 inch (127 mm) 38 caliber guns
4 × single 5 inch (127 mm) 38 caliber guns
8 × quadruple 40 mm 56 caliber guns
46 × single 20 mm 78 caliber guns

Armor: As built:
2.5 to 4 inch (60 to 100 mm) belt
1.5 inch (40 mm) hangar and protectice decks
4 inch (100 mm) bulkheads
1.5 inch (40 mm) STS top and sides of pilot house
2.5 inch (60 mm) top of steering gear

Aircraft carried:As built:90–100 aircraft
1 × deck-edge elevator
2 × centerline elevators
Last edited by aurora on Tue Dec 09, 2014 2:55 pm, edited 1 time in total.
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Re: The Case For (Or Against) Armoured Flight Decks in WW2

Post by alecsandros » Tue Dec 09, 2014 2:39 pm

@Aurora,
IDont remember , but wasnt Indomitable an Illustrious class carrier.. ?

The issue of the topic, as fae as I can understand it, is the usefullness ofthe armored deck in CV construction. My personal impression is that the extra armor added to the British heavy carriers did save them several times in the Mediteranean.

in different theaters, things are mixed. Victorious suffered kamikaza damage of vonsiferably smaller magnitude than USS Franklin. but that came at the price of 50% of aircraft load.

Implacable class did carry more planes but had thinner armor protection than Illustrious class, d would potentialy suffer more damage than them facing the same type of attack.
( but that damage would probably be still smaller than the catastrphies on board non-heavily armored carriers)

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Re: The Case For (Or Against) Armoured Flight Decks in WW2

Post by aurora » Tue Dec 09, 2014 3:16 pm

alecsandros wrote:@Aurora,
IDont remember , but wasnt Indomitable an Illustrious class carrier.. ?

The issue of the topic, as fae as I can understand it, is the usefullness ofthe armored deck in CV construction. My personal impression is that the extra armor added to the British heavy carriers did save them several times in the Mediteranean.

in different theaters, things are mixed. Victorious suffered kamikaza damage of vonsiferably smaller magnitude than USS Franklin. but that came at the price of 50% of aircraft load.

Implacable class did carry more planes but had thinner armor protection than Illustrious class, d would potentialy suffer more damage than them facing the same type of attack.
( but that damage would probably be still smaller than the catastrphies on board non-heavily armored carriers)
Of course alecsandros -I do apologise for the gaffe-Indomitable was the last of the Illustrious Class-hereunder details for Hms Implacable.

Victorious was hit on 4 and 9 May and near-missed on 1 April, but her armoured flight deck resisted the worst of the impacts. She remained on station and was back in operation within hours on each occasion, despite damage to an aircraft lift and steam piping in her superstructure. Three men were killed and 19 of the ship's company were injured. Implacable was not hit in the campaign-she was late on to the scene.

HMS IMPLACABLE
Class & type: Implacable-class aircraft carrier
Displacement: 32,110 long tons (32,630 t) (deep load)
Length: 766 ft 6 in (233.6 m) (o/a)
730 ft (222.5 m) (waterline)
Beam: 95 ft 9 in (29.2 m)
Draught: 29 ft 4 in (8.9 m) (deep load)

Installed power: 148,000 shp (110,000 kW)-8 Admiralty 3-drum boilers-Propulsion: 4 Shafts-4 Geared steam turbines
Speed: 32.5 knots (60.2 km/h; 37.4 mph)
Range: 6,720 nmi (12,450 km; 7,730 mi) at 20 knots (37 km/h; 23 mph)

Complement: 2,300 (1945)

Sensors and processing systems:
1 × Type 277 height-finding radar
1 × Type 279 early-warning radar
1 × Type 281 early-warning radar
6 × Type 282 gunnery radars
4 × Type 285 gunnery radars

Armament: 8 × twin QF 4.5-inch dual-purpose guns
5 × octuple, 1 × quadruple QF 2-pdr anti-aircraft guns
21 × twin, 19 × single Oerlikon 20 mm anti-aircraft guns

Armour:
Waterline belt: 4.5 in (114 mm)
Flight deck: 3 in (76 mm)
Bulkheads: 2 in (51 mm)=-2"
Hangar sides: 2 in (51 mm)
Magazines: 3–4.5 in (76–114 mm)

Aircraft carried: 81

Aviation facilities: 1 catapult
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Re: The Case For (Or Against) Armoured Flight Decks in WW2

Post by alecsandros » Tue Dec 09, 2014 4:32 pm

... Overall I'd say they were successfull designs, for their time and required service.
They were more plagued by lack of sufficient aircraft and lack of sufficient good aircraft to be able to prove themselves more.

as it was, with Victorious carrying ~ 40 planes in 1942/43, and Furious ~ 30-35, a mix of Fulmars, Marlets, Swordfishes, Albacores and Skuas, they had insufficient onboard strength to make a difference in fleet engagements.

On the other side of the planet, the USN and IJN carriers fielded up to 90 combat aircraft in 1942, including Zero, Wildcat, SBD, Val and Kate - all of them very good planes for their time.

---

IMHO, operation Pedestal was a major carrier battle of the war, and should be well regarded , as the 3 British fleet carriers fought bravely against the ~ 600-700 German and Italian planes which tried to destroy the convoy set to Malta.

---

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Re: The Case For (Or Against) Armoured Flight Decks in WW2

Post by aurora » Tue Dec 09, 2014 4:55 pm

All I can say to your post alecsandros- is that I cannot argue with you on all the points you have raised.

Eagle covered Operation Pedestal together with the carriers Victorious and Indomitable. Eagle carried 16 Sea Hurricanes of 801 and 813 Squadrons as well as four reserve aircraft for the operation.

In the early afternoon of 11 August, Eagle was hit by four torpedoes from the German submarine U-73, commanded by Helmut Rosenbaum, and sank within four minutes, 70 nautical miles (130 km; 81 mi) south of Cape Salinas at position 38°3′0″N 3°1′12.00″ECoordinates: 38°3′0″N 3°1′12.00″E.

131 officers and men, mainly from the ship's machinery spaces, were lost in the sinking, Sixteen Sea Hurricanes were lost; four from 801 were aloft when the ship was torpedoed, and landed on other carriers. The destroyers Laforey and Lookout and the tug Jaunty rescued 67 officers and 862 sailors.

NB Eagle was the fourth and last Fleet Carrier to be lost by the Royal Navy in WW2
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Re: The Case For (Or Against) Armoured Flight Decks in WW2

Post by Steve Crandell » Tue Dec 09, 2014 7:31 pm

It's interesting that the prevailing view here is that putting hundreds of tons of armor up at flight deck level has no down side in the other characteristics of the ship other than maybe the number of aircraft carried and that is often argued, although I think the USN ships have larger flight decks. It's particularly interesting in that the height of the armor deck in battleships was argued extensively due to the effect on the ship's stability, particularly when partially flooded.

Two out of 29 Essex class ships were disabled by Kamikazes, which were not foreseen when the ships were designed. Are we to believe that all 29 ships should be saddled with the other undesirable characteristics of an armor deck up on top of the ship in order to save that damage? The USN studied the effect of an armored flight deck as used in the British ships and decided that a thickness sufficient to really matter had so much detrimental effect on the rest of the ship that it wasn't worth it until a very much larger ship could be built where the increased top weight wouldn't be so significant.

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Re: The Case For (Or Against) Armoured Flight Decks in WW2

Post by aurora » Tue Dec 09, 2014 7:49 pm

Steve Crandell wrote:It's interesting that the prevailing view here is that putting hundreds of tons of armor up at flight deck level has no down side in the other characteristics of the ship other than maybe the number of aircraft carried and that is often argued, although I think the USN ships have larger flight decks. It's particularly interesting in that the height of the armor deck in battleships was argued extensively due to the effect on the ship's stability, particularly when partially flooded.

Two out of 29 Essex class ships were disabled by Kamikazes, which were not foreseen when the ships were designed. Are we to believe that all 29 ships should be saddled with the other undesirable characteristics of an armor deck up on top of the ship in order to save that damage? The USN studied the effect of an armored flight deck as used in the British ships and decided that a thickness sufficient to really matter had so much detrimental effect on the rest of the ship that it wasn't worth it until a very much larger ship could be built where the increased top weight wouldn't be so significant.
----------------------------------------------------------------------------------------------------------------- It's particularly interesting in that the height of the armor deck in battleships was argued extensively due to the effect on the ship's stability, particularly when partially flooded.

Well Steve-this thread is do with Armoured Decks for Carriers -Yes/No. Can't say I've noticed a lot of bias; but I do know none of them capsized.As for "saddling the surviving 29 Essex Class CV's with armoured decks"-I can assure you that nothing could be futher from my mind-this is just an exercise in this particular manner of constructing RN Fleet Carriers-right at the beginning, the reason was given that RN carriers should have armoured decks to protect such valuable ships from being sunk faster than GB yards could build them.If you feel we have not dealt sufficiently with the Essex carriers good points that can be quickly rectified-be my guest Sir.
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