Ranger instead of Ark Royal

[T. A. Gardner]

Well...in the photos, they are described a 1000 pounders(kilogram equivalent) in the text they are described as 500 pounders(kilogram equivalent)..

The author's I listed earlier give a detailed account of the attacks on Jean Bart and of the damage.

Also worth noting that they also note that the devastated stern quarter was hit by a 500 pound bomb, 16-inch shell, and the 1000 pound bomb.

The damage shown is by a 1000 lbs. bomb.

The US attacks at Midway were barely coordinated & they had much better weather.

That was strikes by three carriers. Although there was poor or no coordination between the torpedo planes and the dive bombers.

This would be RANGER'S first combat outing, as opposed the combat tested ARK ROYAL.

Ark Royal's air wing actually had little real combat experience against targets at sea even as the pilots were about equally trained in terms of flying hours.

[Richard Anderson]

They don't need armor piercing bombs to do that damage. HC or SAP models would work just fine like the M59 or M65. The 1000 lbs. Mk 33 AP bomb should also be available.

Sorry, but no Terry, to pierce an armored deck like that they do need an AP bomb and until they produced the first 53 1,600-lb AN Mk I in January 1942, there was effectively zero production of such war shots. During the 1930s there were a few test shots manufactured, of which not much is known. The 1,000-lb M59 SAP production began in October 1942. No, the 1,000-lb Mk 33 AP is not available, the first 44 were produced in October 1942.

The 1,000-lb M65 GP is the only possibility, since it began low rate production in January 1941 (fewer than 500 per month through the first half of the year).

[T. A. Gardner]

They don't need armor piercing bombs to do that damage. HC or SAP models would work just fine like the M59 or M65. The 1000 lbs. Mk 33 AP bomb should also be available.

Sorry, but no Terry, to pierce an armored deck like that they do need an AP bomb and until they produced the first 53 1,600-lb AN Mk I in January 1942, there was effectively zero production of such war shots. During the 1930s there were a few test shots manufactured, of which not much is known. The 1,000-lb M59 SAP production began in October 1942. No, the 1,000-lb Mk 33 AP is not available, the first 44 were produced in October 1942.

The 1,000-lb M65 GP is the only possibility, since it began low rate production in January 1941 (fewer than 500 per month through the first half of the year).

You are missing my point. The bombs don't have to pierce the armored deck. All they have to do is wreck the superstructure and unarmored / lightly armored hull causing systems failures, fires, and flooding. Even HC and SAP bombs will do that. Bismarck down by the bow with thousands of tons of water in compartments and taking green water over the forward deck would be lucky to keep Anton and Bruno turrets in action. Between the PoW's hit forward causing flooding and a 1000 lbs. bomb hit demolishing enough deck and hull above the waterline like on Jean Bart Bismarck would be slowed dramatically in a seaway due to the flooding. That would be nearly as crippling as the rudder hit.
A hit amidships that causes a fire in the hangers or on the boat deck would be a serious issue.

You don't have to penetrate the main armor system on a battleship to render it hors de combat.

[Orwell1984]

The bulk of the damage to the Jean Bart was caused by the shellfire from USS Massachusetts.
French damage reports make this clear.
This thread contains details from French Battleships, 1922-1956 by John Jordan and Robert Dumas
http://www.kbismarck.org/forum/viewtopic.php?t=6552

Relevant information:

0718 - JEAN BART damaged by two 500lb bomb hits in an initial air attack: one bomb struck the port catapult mount which caused "a small fire and flooding of the manual steering compartment"; a second bomb "struck the quay to starboard, causing a large breech in the outer hull plating in section M".

0725 - First hit by MASSACHUSETTS on shelter deck aft, seven minutes later, passed through both armored decks and exploded in the empty 152mm magazine compartment. French examination of the path of the hit (which passed through four decks) estimated striking angle relative to the ship's decks as 33 degrees. The line of fire of MASSACHUSETTS for this hit, judging from the damage diagrams given in the book, was approximately 30deg off the starboard bow of JEAN BART. Any flooding suffered by JEAN BART as a result of the aerial bomb hit on the quay would have produced a list to starboard, which would have effectively increased the angle of presentation of her decks to an projectile approaching from that side.

Further information taken from thread above:

At 0737 a second shell hit Jean Bart to starboard just aft of the funnel which exited the ship just above the waterline forward of the port 152mm barbette. At sea this shell would likely have resulted in local flooding above the armored deck.

The next hit was made at 0806 striking Turret I at an oblique angle glancing off the 6" barbette armor. This armor was badly gouged by this strike resulting in a jamming of the turret in train. In action at sea this would have taken the turret out of action. As it was this turret was unable to operate for over ten hours while a local contractor cut away the damaged area.

A second shell from this salvo struck Turret II's barbette (this turret was not complete and non-operational) also at a very oblique angle continuing aft into the ship's hull. There it wrecked a number of spaces coming to rest next to the communications tube connecting the conning tower.

The last shell struck starboard aft just ahead of the starboard catapult mounting. This shell penetrated the 4" armor protecting the steering gear and detonated just above the keel. Jean Bart 's steering gear was largely wrecked by this hit.

I'll dig out my copy of Jordan's book and edit in the page numbers when I get back home. (Edit damage is covered from pages 158 to 161 and includes diagrams outlining the path and damage caused by each shell hit. Of the bomb damage, the most effective bomb appears to have been the second 1000 lb bomb dropped on Nov. 10 . it should be noted that of the 9 Dauntlesses on this mission only two hit the Jean Bart which was stationary and tied to the dock. So a less than 25% hit rate against a stationary target)
I'll also check Cressman's history of the USS Ranger and see if he provides any more details about the attack on the Jean Bart.

[AnchorSteam]

It is terrifying to think about the possible result if successful.
Could the Devastator have done it, and come out of this with such a good reputation that the Avenger project was de-prioritized?

Dear god.... what would the 2nd half of 1942 in the Pacific War have looked like?


Alternatively, what if the Bismarck had made it? Wouldn't it have bottled-up the same way the Battle-Cruisers were, and had to play the same game of tag with mines all the way home six months later?

[Richard Anderson]

Its complicated, as usual. The 8 November attack is not well recorded, but all 17 aircraft dispatched to the harbor between 0615 and 0635 on the morning of 8 November were armed with 500-lb GP, probably AN M64 or AN M43. Only one reportedly struck Jean Bart. According to French records, only two bombs were effective, the two on the morning of 8 November. One did minor damaged to the catapult mount, started a fire, and caused minor leakage. The second, which hit the quayside, exploded in the water and cut a "notch in her bilge" underwater, but otherwise did no serious damage. None of that damage is pictured in the photos posted here.

Nine aircraft were launched with 1,000-lb M65 GP at 1416 on 10 November. They claimed seven direct hits and two near misses (later amended to five direct hits and four near misses). The French recorded two hits. One struck the forward starboard anchor windlass, destroying it and setting a small fire. The second hit the starboard quarterdeck and destroyed the starboard catapult, damaged 30 meters of superstructure and upended the catapult itself, which made the damage appear more spectacular than it was. It caused an electrical short circuit, which was repaired in a few minutes, and minor leakage in Boiler Room No. 2. Warship International, Vol. 3, No. 4 (APRIL 1966), pp. 95-101.

None of these four hits did anything other than superficial damage to the superstructure, while causing minor leaks that were quickly patched. The damage to the port catapult can be partly seen in the first photo you posted, but it is badly obscured by the two 16-inch hit from Massachusetts that struck this area. One hit starboard just aft of the funnel and exited just above the waterline forward of the port 152mm barbette, while the other hit starboard just ahead of the starboard catapult mounting, penetrated the 4" armor protecting the steering gear and detonated just above the keel, wrecking the steering gear and doing a massive amount of damage.

[EwenS]

So far no one has yet mentioned the weather.

On 26th May 1941 Ark Royal flew off a search at 0835 in wind Force 7 (i.e. 28-33 knot wind 13-19 foot waves), overcast, and visibility 10-12 miles. Her round down was reported to be rising and falling up to 56 feet. Later that day when the Swordfish were landed on after mistakenly attacking Sheffield, 3 had their undercarriages smashed by the rising deck. At 1900 when she launched the next strike the wind was blowing 50 knots (i.e. Force 10, 48-55 knots, 29-41 foot waves). 3 Swordfish crashed while landing after that strike.

A Swordfish landed at 60 knots, an SB2U at 75 knots.

My question is whether Ranger could even have operated her aircraft in those conditions. While slightly longer than Ark Royal at the waterline, she was narrower and only 2/3 the tonnage. Even pre-war she had a reputation as being unable to operate in common Pacific swells as comfortably as larger carriers. And weather in the Atlantic was generally worse than the Pacific. So seemingly much more likely to be tossed around in an Atlantic gale.

Even if she could operate aircraft, given the conditions, could an SB2U lug a 1,000lb bomb off the deck or would they be limited to 500 lb bombs? From the damage reports about the Jean Bart, it would take the larger weapon to do any serious damage to Bismarck, always assuming it could be delivered against a moving and manoeuvering target.

When Ranger operated off North Africa in Nov 1942 and with the Home Fleet in Oct 1943, the weather during her strikes was much better.

[T. A. Gardner]

Good question. Ranger might not have. Of all the British carriers, Ark Royal had the highest flight deck above waterline (66 feet) due to her double hanger arrangement. But I don't know which is a better sea keeper in terms of hull design. Ark Royal does have bilge keels fitted that would indicate a rolling issue trying to be damped out, but I can't say that one or the other is definitively better in this respect.

[EKB]

If the Swordfish did not score a lucky torpedo hit on the port rudder of Bismarck, the battle may have ended differently.

Don’t forget the large number of air raids mounted against the Tirpitz when the ship was anchored in Norway. Even when stationary, a giant bomb was required to destroy the target.

[Carl Schwamberger]

...
Alternatively, what if the Bismarck had made it? Wouldn't it have bottled-up the same way the Battle-Cruisers were, and had to play the same game of tag with mines all the way home six months later?

Thats near a given since the Bismarck already had hull damage from its earlier surface battle. In the subsequent months it became clear the embryonic raider fleet could not operate from the French Atlantic ports. The dry dock of St Nazaire was becoming more of a trap than succor So, the Bismarck is off to the North Sea/Batic ports with the rest of the pack.

[EwenS]

It is terrifying to think about the possible result if successful.
Could the Devastator have done it, and come out of this with such a good reputation that the Avenger project was de-prioritized?

Dear god.... what would the 2nd half of 1942 in the Pacific War have looked like?

Makes no difference at all to the 1942 position.

There were only 130 Devastators built between 1937 and 1939. So it was already a diminishing asset in 1941 through the normal wastage of carrier ops especially with the prospect of new carrier groups being formed.

The path of succession was already fixed by May 1941. The Avenger prototypes had been ordered in April 1940 followed closely by prototypes of the Vought XTBU-1. They flew in Aug and Dec 1941 respectively. The latter actually had better performance than the Avenger but Vought was tied up in other projects (e.g. the F4U-1 Corsair) so it was the Avenger that entered production in Jan 1942. Eventually the production contact for the TBU went to Consolidated who built 180 of 1000 ordered from late 1943 as the TBY Sea Wolf.

[Carl Schwamberger]

Here is a link to a near identical discussion from last May. The Ranger & Wasp vs the Bismarck starts partway through, late page two & has a bit more detail than this discussion.

viewtopic.php?f=11&t=231472&hilit=Range ... k&start=60

[Andy H]

Hi

Just some food for thought

In Albert Nofis work, To Train the Fleet he states that though carrier dive bombers demonstrated a higher likelihood of hitting a moving ship than did high-level bombers, those hit percentages were not that particularly impressive in actual combat: around 15% throughout the war.

Norman Friedman notes in his book US Aircraft Carriers the largest anti-ship weapon for carrier based dive-bombers was a 1000pounder, which proved ineffective against battleship armour. In fact, no deck armour over ship vital spaces of a new battleship was ever penetrated by a bomb delivered in a dive.

Alan Zimm comments in Attack on Pearl Harbour: Strategy, Combat, Myths Deceptions that the probability of hitting a ship maneuvering at sea was equivalent to that of a bomb, 15%.

Regards

Andy H

[Takao]

In fact, no deck armour over ship vital spaces of a new battleship was ever penetrated by a bomb delivered in a dive.

Well, that is not entirely true.

The Tirpitz was pierced once by an FAA 1,600 pound AP bomb, hit #1 on 24 August, 1944, but the weapon failed to detonate. The bomb penetrated the upper deck, battery deck, armor deck, upper platform deck, and middle platform deck.

[EwenS]

The 1600lb bomb used by the FAA was of US origin, coming into service in May 1942, but used very little and with only 20 or so carried by each carrier. The main US AP weapon was the 1000lb.

The US estimated 7 AP penetrating hits to sink a battleship and the Japanese 12-16. US analysts later concluded that a 1000lb M33 AP bomb would only sink a battleship if it hit a magazine. That then equated to a 79% probability of sinking a battleship with 6 penetrating hits. Don’t ask me how the maths works on that one!
http://pwencycl.kgbudge.com/B/o/Bombs.htm