The USN Cherrytrees – The Lexington class Part 3/3

Author’s note: Before we move on to the 3rd and final chapter I need to make a slight correction and an addition to the first two parts.

Correction: Further research reveals that the numbered designs mentioned in Part 1’s Bumpy road chapter are indeed starting with design No. 101, which was one of the prelimiary designs made for BB#40 NEW MEXICO on 19 Nov 1913. The series contained all ship types not just cruisers and ran up to at least the BB-57 class of 1939 which started at design No. 454. So while no comprehensive list is given it still provides valuable time-line comparison as designs were numbered in sequence of creation and irrelevant of which design effort or ship type it supported.

Addition: I’ve got quite a lot of comments on several forums regarding my remarks on the protection of the finished battlecruiser design and also on the concept’s further (’20s) validity. I think it is worth to add some lines here to clear things up a bit.

1.\ First of all on the protection issue I have to reiterate that these ships were scouts  in the first place and were not meant to fully stand up to the fire of battleships for an extended period of time. It is erroneus to think that the USN would have committed them the same way the Royal Navy used their battlecruiser at Jütland. The armor was designed on cruisre practice levels, which meant 60 degreee target angles instead of 90 degree (or perpendicular) that was standard for battleships. This alone substantially increased the protection offered even by the marginal belt armor. Furthrmore these ships were a lot bigger than contemporary battleships meaning they had proportionatly greater protected hull volume. This is thanks to the fixed percentage armor length and the high freeboards – both factors contributing greatly to the enormous size as discussed in the early designs chapter. All in all more penetrating hits were needed make the ship succumb to gunnery fire alone provided that no magazine hits are achieved – but evidently the barbettes and turrets had a magnitude better armor for this very reason. While far from being inpenetrable, these ships had to fight first and foremost versus ~6″ gun armed light cruisers and probably earlier generation battlecruisers (usually having no more than 14″ guns). The only really comparable ships,  REPULSE, RENOWN and HOOD and probably the Japanese AMAGI class battlecruisers admittedly had similar or better protection while at the same time were still a good 1,5-2 knots slower. What’s more the 16″/50 Mark 2 guns on the LEXINGTON were among these adversaries probably the most powerful and had the flattest trajectory at likely battle ranges. The only clearly superior design would have been the G3 type of the Royal Navy which I think can clearly be considered as a fast battleship – but then again the G3 brings up the issue of too high a unit price of the mixed type for any nation to build a whole battlefleet entirely out of them.

2.\ Validity of the strategic scout concept in the ’20s (and maybe ’30s) versus the aircraft carrier: I think we have to remind ourselves that the aircraft of the day were still too slow, short legged and prone to bad weather limitations to entirely base the startegic scouting role on them. What’s more as we willl see from the upcoming part the carriers competed for the very same resources as the CCs (no wonder they got converted when the CC type was banned Washington). So the CV essentially traded scouting range for the offensive main armament of the CC. The latter was arguably more powerful and devastating for the day while it had lesser range, the former arguably better ranging but only really useful in good weather conditions. Also it was likely that a major adversary would field it’s own carriers and their fighters will prevent the carrier’s planes from mainly used in the scouting role. To stop the capital cruiser however required major fleet units, degrading the enemy’s battleline strength substantially unless they were of the above mentioned ship classes. This is exactly due to the capital cruiser’s main gun deterrence factor and it’s obvious edge over normal screening units. I think it can be argued realistically that the strategic scout role declined in reverse proportion to the aeroplanes  gaining in potential (especially dive/scout bombers). At around the same time a third type of ship, the submarine also entered into the competition for being the navy’s strategic scout, however it’s potential was not fully realized until surface search radar was compact and at the same time powerful enough to be mounted on submarines. Up to that point they were hardly better than the small four stacker DDs pushed into the same role during the navy excercises in the 1910s.

And now onto the 3rd part :).

Reincarnation

 

Despite urban legends stating it otherwise, those conservative black shoe, gun club admirals suggested procuring aircraft-carriers as far back as 1918 and they wanted large, powerful units at that. They saw the aircraft carriers value as a perfect supplemet to the battleline, as a more modern form of a „battlecruiser” if you like. The characteristics sought by the General Board described a ship with 250 meters length and 35 knots speed which was close enough to the then building LEXINGTON class BCs to be a base for an aircraft carrier study (it was still the 34,800 ton 35 knots version of LEX). At that time it was suggested only as an expedient to the carrier design, nobody really though that the BCs would get cancelled and then converted.

Fiscal Year 1920 and 1921 saw no approval for carriers from Congress. Though no keel laying took place before Aug 1920 on the BCs some plans were already in the making by the summer of 1921 to turn them into aircraft carriers. After a lengthy debate on the preferred aircraft carrier tpye to choose (that is many small 10.000 ton range units or a few big 30.000 ton ones would be better) the first plans for big carriers were ready by Nov 1920. The plans showed very modern features at those times, like a full island on the starboard side and catapults recessed into the flight deck. Since the size and hull shape was very close to the BCs on the building ways General Board wanted the design adapted to their hull lines

 

KÉP12
15. Figure: the carrier design, not yet redrawn tor the battlecruiser hull lines
CarrierSchemeB
15B Artist concept of Design B (by TZoli)

Almost paralel to this preparations for the Washington Treaty conference were underway and it was crystal clear that the very expensive BCs will be among the first to go.

Since a new carrier would have cost 27 millions compared to 22 millions for a conversion it just made sense to try. Using materials for the least advanced USS RANGER CC-4 even more could be saved. In the end the Treaty itself eased the decision: only two can be converted so again the sensible decision was to choose the two most advanced to save time, money, material and effort. These were the well know LEXINGTON and SARATOGA, now CV-2 and CV-3 respectively.

Accroding to the fresh treaty the allowed displacement for these units was 33.000 tons. At the beginning it looked like this limit would make things complicated or even impossible (proposals as radical as removing half of the machinery were put forward to reduce weight) but in the end a loophole was played out. The treaty permitted 3000 tons of anti torpedo and anti air protection built into existing ships during modernizations. This way the ships fitted, but just barely into the 36.000 tons aggregate displacement.

The hulls were kept almost the same with minimal changes: height of the armour belt was reduced, freeboard was increased as the new strength deck became the flight deck. This resulted in the only closed hangar US carriers for 40 years. The hull narrowed in finer lines aft compared to the original carrier design so the after gun turrets placed on the sides were relocated right aft of the huge funnel that in itself was a separate superstructure on the starboard side. The gigantic smokestack was the most remarkable visual feature of these two ships, almost symbolic.

Armament was 4 twin 203mm guns in compliance with treaty regulations. These guns were thought to be necessary against the 10.000 ton heavy cruisers armed with 203mm guns, a category which was just created by the very same Washington Treaty. Secondary armament composed of 12 single 127mm/25 guns placed at four gallerys (3 each) at the four corners of the flight deck. Two aircraft elevators were fitted on the centerline, next to the island and funnel. The flight deck followed the hull lines at the bow in it’s width but at the stern it retained it’s full width in it’s entire length. Due to the weight of the island, the huge funnel and the four gun turrets and due to the very fine hull lines aft both ships trimmed substantially to the starboard and aft in normal condition. To counteract this the starboard side fuel tanks were rarely filled, decreasing the range somewhat.

At the outset quite a few questions remained if the two huge converted carriers are the right choice out of a strict and tight total tonnage allotted for aircraft carriers (72.000 tons ot ouf 135.000) but the coming decades and mainly the Fleet Problem manuvers proved the worth of these vessels.

The irony of the whole story is that LEXINGTON and SARATOGA became one of the most succesful prototypes of the new category of capital ships that made their original battlecruiser concept obsolete.

Conversion to carrier on both units finished in 1927-28 and after this they spent 95% of their service life as members of the Pacific Fleet.

Their flight decks saw probably the widest variety of aircraft types within the US Navy’s carriers (especially SARA). In the period of 1927-1938 aircrafts evolved in a fewerish pace, sometimes new types came bi-yearly or even every single year: newer planes were faster, more manuverable and could carry more loads further. This had two impacts on the ships. First their primarily scouting and supporting role started to transform into an attack-power projection role and increased their military value further and further. On the other hand they could meet the demands of newer planes less and less. Especially problematic were the small enclosed hangar and the very slow and small lifts together with the narrowing flight deck at the bow. Also the 8″/203mm gun turrets were viewed less and less useful (though Adm. King propsed to retain them as late as 1942) especially in light of the usually heavy escort screen these ships operated with normally. At the same time the rapidly evolving dive bomber planes and their tactics demanded more and more fast firing automatic anti-aircraft weapons – but these two ships in contrast to later carriers had no gallery decks so there was no obvious place where to put these weapons.

In 1936 the LEXINGTON had her bow widened and stregthened and four small galleries were fitted, two at the bow and two at the stern in order to house machine guns. With the very same purpose a small balcony was built around the funnel at 4/5 of it’s height. Evidence uncovered just recently shows that SARATOGA had a similar balcony as well though fitted a bit lower compared to her sister.

Further 0.5”/12.7mm AA guns were placed on top of the twin main battery turrets – though ship’s captains wanted these turrets removed altogether. These modifications increased displacement by about 2000 tons.

It was becoming more obvious by the day that these ships were in for a major modernization if they were to continue service as front line units.

To faciliate this a plan was formulated for modernization:

  • extend the flight deck at the bow to full width
  • fitting a bulge to the starboard side to compensate for the island’s weight and restore lost buoyancy over the years
  • fitting of radars and modern catapults
  • further expansion of medium and light AA batteries

In 1940, with a new war on the horizon both units were fitted with locally controlled 76mm single AA guns. 4 went to the 4 small galleries at the extremities of the flight deck, the fifth was fitted between the island and funnel. These mounts were progressively changed to 28mm quad AA guns. Sources vary on the bow flight extension for SARATOGA, more recent findings show that it was done in Aug 1941 together with the new gun galleries (both funnel and flight deck edges) and she even had radar fitted and the flight deck extended aft as well. The most serious modification, the fitting of the bulge would have taken weeks therefore it had to wait as world affairs developed in a way that none of these powerful units could be spared for that long.

Sara
16. Figure: Saratoga’s funnel AA gallery

 

From 7th Dec 1941 war shaped the fate of these two magnificent vessels. LEXINGTON was on a ferry trip with planes and was just headed to Pearl while SARATOGA anchored in San Diego.

The LEXINGTON took part in many of the raids and ferry missions of the early month, collecting valuable experience in the process. In April at the request of her captain the four 203mm gun turrets were finally landed and in their place came additional 28mm AA guns. The remaining 12,7mm guns were all replaced by 20mm Oerlikons and even some extra mounts were fitted, making LEXINGTON probably the best defended ship in the fleet (that is against aerial threats). She got a CXAM air search set at the leading tip of her funnel and a small raked funnel cap was fitted behind it for smoke protection.

After the overhaul she operated in the South Pacific, in the area of Rabaul. At the end of April under the command of Adm. Fitch she joined YORKTOWN in the Coral Sea to stop the japanese advance towards Port Moresby. May 7th and 8th saw the first carrier battle in history that we know now as the Battle of Coral Sea. Lexington actively participated in strikes against SHOHO and SHOKAKU. The japanese counterstrike of the 8th was concentrated on the larger, more sluggish LEXINGTON. She took two bomb hits and two torpedo hits, none of them seemed to be serious. She was down by the a bow a bit from one of the torpedo hits but overall the TDS that caused so much headache during the design process seemed to be doing it’s job very well. Unfortunatelly the bow aircraft fuel tank got ruptured from the shock damage caused by the torpedo hit and the evaporation from it filled the forward part of the ship, a recipe for disaster. It took only a spark from possibly the forward generator room to ignite the gasses that caused severe internal wounds through explosion of ready use 127mm ammo and reignited the fires that had been just put out. The ship seemed to be lost as more and more explosions rocked it. Destroyer PHELPS was ordered to sink „Lady Lex” as the crew called the wounded carrier with torpedoes and she complied.

 

The SARATOGA – „Sister Sara” – spent much of 1942 in port. She got torpedoed by the japanese submarine I-16 on the 11th January 1942 just out of Pearl. One torpedo hit at the port side with only moderate damage – the famous TDS worked very well again, the main bulkhead was not penetrated. Still the ship was sent to Bremerton for repairs and the time was now to fit the long overdue bulges. It took 4 month to transform SARATOGA from an old veteran into one of the most modernd and best protected carriers of the USN. She got her huge bulge on the staroard and a smaller one at port, making her the second assimetrical hull american warship and the first that did not fit through the Panama Canal. The huge funnel was cut down one level to save weight and clear sky arks. The island was made open top and it’s main tripod mast replaced with a lighter pole mast. The 203mm turrets were gone, in their place came spanking new 5”/127mm/38 turrets that were intended for CLEVELAND class cruiser converted to light carriers. Even the 12 older 127mm/25 guns were replaced by single open mount 127mm/38s. A lot of additional 28mm „Chicago pianos” and 20mm Oerlikons were fitted as well as a brand new set of radars. By 1st June SARATOGA emerged as the most modern carrier in the USN and probably in the world. Unfortunately she missed the Battle of Midway by a few days though. From August she participated in the fights around the Solomons chain where she took part in the 3rd carrier battle of the war at the Battle of Eastern Solomons. Her planes attacked and sunk the japanese carrier RYUJO.

She couldn’t enjoy her fame too long as she got torpedoed again by the submarine I-26. Time and again the TDS proved it’s worht but in this occurance there was short circuiting on her main machinery switchboard due to shock damage. SARATOGA was dead in the water for a considerable time and it was only luck that I-26 did not attack again. This damage shed light on the shrotcomings of the turbo electric drive as it was very susceptibel to shock damage and short circuiting. The repeated torpedoing of the huge and long ship also showed that with it’s single rudder she was a pig when it came to turning (she had the worst turning circle in the entire US Navy) and also showed the wisdom of putting back the TDS into the design as opposed to the original concept. Fortunately she made back to Pearl on her own power later on and got repaired by mid November (also she had her 28mms replaced by 40mm Boforses). She was back in action in the south soon and spent the next 12 month in support of the operations there and was for a time the one and only operable USN aircraft carrier. In November 1943 she made a brilliant attack on japanese heavy cruisers concentrated and anchored at Rabaul, inflicting heavy damage on them then she proceeded to the actions against the Gilbert islands.

KÉP13
17. Figure: The ominous TDS and the damage suffered in early 1942

After this tumultous year without any overhaul she was back into the yards for some rust scraping and equipment upgrade. In Jan 1944 the ship emerged from the yard with her final layout and armament, sporting no less than 60 barrels of 40mm Boforses and 32 barrels of 20mm Oerlikons (in addition to the sixteen 127mm guns) together with an advanced radar fit and renovated aircraft lifts. She displaced an astonishing 52.000  tons in full load condition (her overladed state shows very well in that she had her starboard anchor removed….)

In February she was back in action at  the Marshall island then embarked on a new marathon mission: she joined the British Eastern Fleet at Trincomalee to bolster strength there. SARATOGA operated there in a lot of island attacks and smaller missions and finally returned to overhaul in June 1944.

After this she became a night carrier and operated mostly around Pearl Harbor to practice tactics. Due to her still high fighting value and experience she was emplyed in combat as a night carrier in actions against Iwo Jima in early 1945. On 21st Feb she was hit by no less than 6 kamikazes and her flight deck sustained severe damage. Although Sister Sara got repaired one last time she participated in no more military actions. In 1946 this proud old carrier was the center and main target of the nuclear tests at Bikini atoll. During the second, Baker test when the bomb was detonated under water she suffered fatal damage from the shockwaves and sunk in situ (click link for video). Her hulk is still in place today.

 

 

 

Sources:

 

Norman Friedman  – US Cruisers, An Illustrated Design History

Norman Friedman – US Carriers, An Illustrated Design History

Norman Friedman – Battleships, Design and Development 1905-1945

Siegfrid Breyer – Schlachtschiffe und Schlachtkreuzer 1905-1970

Robert C. Stern – The Lexington Class Carriers

Trent Hone – High Speed Thoroughbreds – Warship 2011

Naval Historical Center – Online Library of Selected Images (now hosted by shipscribe.com at: http://shipscribe.com/styles/index.html)

 

Special thanks go to Charles Haberlein of Naval Historical Center who arranged for many of the Spring Style drawaings getting scanned from the archives after my constant e-mail requests.

 

And last but not least a huge thanks goes to Zoltán Takács (TZoli) for his continued efforts in providing the beautiful drawings according to my needs.

 

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