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Yorktown - first modern US carrier |
CV 5 Yorktown
Class: Yorktown CV 5 1937,
30 September: commissioned
Enterprise CV 6 1938,
12 May
Hornet CV 8 1941,
20 October
Displacement:
19,875 tons standard
25,500 tons deep displacement
Length:
809ft 6in / 246.6m overall
770ft / 234.6m waterline
802 x 86ft flight deck
244.3 x 26.2m
Beam: 83ft 3in / 25.4m
Draught:
21ft 6in / 6.5m standard
26ft / 7.9m deep load
Aircraft: 96
Crew: 1,875 men
Armament (as completed):
5in / 127mm guns x 8
1.1in / 28mm guns x 16
0.5in / 12.7mm mg x 24
Armor:
2.5 – 4in / 64 – 102mm vertical belt
1.5in / 38mm deck
Machinery:
Geared steam turbines
9 boilers
4 shafts
Power:
120,000 hp / 89,500 kW
32.5 knots
Range: 12,000nm / 22,220km @ 15 knots
Fuel: 4,300 tons
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Note biplanes on crowded flight deck |
The Yorktown, CV 5, was the first in a
series of three carriers that included the legendary Enterprise, CV 6, and the Hornet,
CV 8, famous for the Doolittle Raid on Tokyo in 1942. The design of the Yorktown class of carriers was the result of compromise between
treaty restrictions and fleet experience with large carriers. The Washington Naval Treaty of 1922 was an
agreement primarily between Britain, Japan and the United States to limit the
number of their warships. Its effect was
to hold the size of the Yorktown to
20,000 tons. Experience with the 36,000
ton Lexington and her sister carrier,
the Saratoga, demonstrated the
offensive capability of large ships carrying extensive air wings. By contrast the 14,500 ton Ranger was considered a failure by the
Navy because it was inadequately powered, poorly protected and its aerial
operations were too easily disrupted by rough seas.
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With tanker in Coral Sea |
Despite Yorktown’s compromised size it would be
the first true modern carrier of the United States and it would provide the
basis for the next-generation Essex
class carriers that emerged with great impact during the Second World War. The Lexington
class carriers were battle cruiser conversions and lacked the efficiencies that
might have come with being designed as a carrier from the keel up. The Navy could have improved on the
Yorktown’s protection had it build the ship closer to 27,000 tons but then
treaty limits would have limited carrier production to just it and the Enterprise. Navy admirals wanted three ships so the Yorktown class carriers were reduced by
7,000 tons, enabling a third Ranger-size
carrier to be built – the Wasp. Unfortunately the Wasp suffered from the same vulnerabilities as did the Ranger and it was sunk by torpedoes
within three months of being introduced to the Pacific Theater in 1942.
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Struck by torpedo at Coral Sea |
Carrier
speed is important when operating with the fleet and the Yorktown, like the Lexington
that preceded it, was as fast as the heavy cruisers that were its escort. These ships could top 32 knots when
needed. Launching heavy aircraft from a short
deck is not as dangerous as landing on that same pitching deck but it is a
challenge having its own peril. A plane
falling into the drink from an unsuccessful launch is almost always fatal –
being that it’s in the path of the oncoming carrier. Carriers divert from the fleet’s course when
needed to launch into the wind. Its
speed and oncoming wind combine to maximize the plane’s lift but it also means
the carrier must quickly regain lost ground with the fleet after the planes are
launched. Smaller carriers like the Ranger and Wasp weren't large enough to hold the massive power plants
necessary to generate fleet carrier speed.
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Recovering from dive bomber attack |
Both the Lexington and Saratoga came initially with eight inch guns and the armor needed
to do battle with an enemy cruiser.
These were America’s first real carriers and it was believed they would
have to hold their own in battle with surface ships. The armor and large guns needed for this role
created a substantial weight penalty for the carrier. At this time the aircraft carrier’s purpose
was primarily to provide reconnaissance for the Navy’s large battleships. The biplanes that populated the carrier’s air
wing were too light and underpowered to be anything more than pesky gnats when
it came to a clash between twelve inch guns and foot thick armor. During the 1930s the transition was made to
heavy, more powerful monoplanes and it became increasingly evident that the
carrier was by itself an offensive force of reckoning. The carrier’s defense was not measured in
guns and armor but in the size of the air wing it carried. The measure of its power was in getting all
your planes into the air in the shortest possible time.
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Dealing with bomb damage below deck |
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Getting quick patch-up at Pearl |
By now dive
bombing techniques had countered a ship’s ability to rapidly maneuver out of
the way of plane-dropped bombs. Aircraft
had become muscular enough to make airborne torpedo attacks lethal for most any
naval vessel. By 1940 a carrier’s air
wing was a mix of fighters for defense and the offensive power supplied by dive
bombers and torpedo planes. Just prior
to December 7, 1941 the Yorktown’s
mix of fighters and bombers was typical for the time. It consisted of:
Fighters: F4F Wildcat – 19
Dive Bombers: SBD Dauntless – 36
Torpedo plane: TBD Devastator – 18
Normally
there were a few additional planes stored on the hanger deck as a reserve. The torpedo plane could also be used as a
horizontal bomber but this approach was rarely effective in naval battle. Dive bombers were used for scouting duty by
replacing bombs with external fuel tanks and fighters could provide escort to
the carrier’s bombers.
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Dousing fires at Midway |
The
installation of radar on the fleet’s carriers in 1940 significantly enhanced
the effectiveness of the carrier’s fighter protection. Approaching aircraft could now be identified
from 70 miles out giving the flattop time to beef up its routine combat air
patrol circling overhead. One possible
hitch was the displacement of aircraft on the flight deck. Whereas the British and Japanese policy was
to store aircraft on the hanger deck, American naval practice was to have as
much of the air wing as possible positioned on the flight deck. This arrangement saved time in getting all
your planes airborne. The obvious
problem occurred when you wanted to launch specific aircraft that happened to
be at the rear of the pack. Placing the
fighters at the front made them immediately available for rapid defensive
response but it didn't provide space needed for landing when it came time to
refuel. This brings up one of the
advantages of having two carriers working in tandem. One flattop could have its flight deck loaded
and ready for offensive action while the second carrier could keep its flight
deck cleared of all aircraft but fighters, dedicated to providing the necessary
overhead combat patrol.
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Destroyer takes torpedo intended for Yorktown |
In practice,
the task force surrounding the carrier, whether American or Japanese, was
always searching for the opposing carriers.
Discovery of an enemy’s carriers invariably resulted in a quick launch
of the task force’s complete air wing. Whoever
struck first was the most likely victor.
The age of the aircraft carrier had arrived. Knock out an enemy’s carriers and their
surface ships must either flee the scene or risk being sent to the bottom of
the sea from a swarm of airborne bombs and torpedoes. The battleship has an offensive reach of no
more than twenty miles. Aircraft from a
carrier can strike suddenly out of the blue from their floating base two
hundred miles away. This was
dramatically demonstrated at Pearl Harbor and, again, at Midway six months
later.
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Bomb punches through wooden flight deck |
The Japanese
were slow to appreciate the defensive need for radar. Had their carriers at Midway not relied
exclusively on air patrols they might have been able to counter the devastating
blow inflicted on them by the squadrons of SBD Dauntless that pounced
unexpectedly from nearly straight overhead.
Like their American counterparts, the flight decks of Japanese carriers
were not armored. Effective armor would
have made them top heavy and would have required them to make unacceptable cuts
in the number of aircraft they carried.
This vulnerability made dive bombing possibly the greatest risk to a
carrier’s survival. One well-place bomb
could leave the flight deck unavailable for further aircraft operations. Fighters were the best means of carrier
defense. By the time of the Battle of
the East Solomons, in August, 1942, both the Enterprise and the Saratoga
had doubled their fighter complement to 36 F4F Wildcats. The Yorktown
might have done likewise had it not been sunk at Midway – sent to the bottom by
a submarine’s two torpedoes, having first been slowed from three bombs in a
dive bombing attack.
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Destroyer pulls survivors from water |
It took an
extraordinary effort on the part of repair crews at Pearl Harbor for the Yorktown to even make it to Midway. The vessel managed to survive three bomb hits
and two torpedoes to her port side at the Battle of the Coral Sea just the
previous month. At Pearl the Yorktown was given a quick 48 hour patch
job and sent back to sea along with her sister ships, the Enterprise and Hornet. Yorktown’s
squadron of SBD Dauntless would be responsible for sinking the Japanese carrier
Soryu while dive bombers from the
Enterprise would destroy both the carriers Kaga
and Akagi. A last gasp attack from the carrier Hiryu led to the Yorktown’s demise. Hiryu, the fourth and final Japanese
carrier, was itself dispatched the following day. The entire battle had been waged without
either fleet sighting the other except from the air.
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Yorktown capsizes and sinks |
The design
of the Yorktown, CV 5, displays the
confidence the US Navy had developed for the offensive role the aircraft
carrier brought to the fleet. This
respect was first earned in fleet exercises by the Lexington and Saratoga
during the twenties and early thirties.
The Navy’s faith in a carrier-based task force would be vindicated in
battle during the first difficult months of the Second World War by Yorktown and her sister ships, Enterprise and Hornet. They would each
achieve a distinguished place in history.
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Yorktown in its early days |