Sea planes on destroyers. Seaplanes were so valuable aboard battleships and cruisers for scouting, anti-submarine and communications that five destroyers were ordered to be equipped to carry them in May 1940. The idea turned out to be impractical and several planned installations were canceled and those installed were ordered removed in Oct 1943.
Athwartship, hanger deck catapults. Those authorized for installation on 11 carriers were removed after 17Feb42 and replaced with a second flight deck catapult.
Cruiser Guns on Carriers. Eight 8" guns were originally on Lexington and Saratoga and replaced by anti-aircraft guns in April 1942.
Towed Fighters. The idea was to increase the range of small planes. Two F4F's hooked to tow lines streamed behind a twin-engine Army A-20, cut their engines and were towed for an hour at 180 knots at 7,000 feet on 10May42.
Cruise Missiles. TV guided assault bombs were under development
from before U.S. entry into the war. They never made it into combat
although tests were successful as early as April 1942.
22Mar40--Development of guided missiles was initiated at the Naval Aircraft Factory with the establishment of a project for adapting radio controls to a torpedo-carrying TG-2 raining glider.
However, German radio controlled glider bombs were used against the U.S. fleet of Salerno, Italy, 11Sep43, where Savannah and Philadelphia were damaged. DE-137 was damaged off Anzio, 15Feb44. LST-282 was sunk by a glide bomb off St. Tropez, France, 15August1944
17June42. Development initiated for Pelican, an antisubmarine guided missile, consisted of a glide bomb which could automatically home on a radar beam reflected from the target
18Sept44--The Pelican guided missile production program was terminated and the project returned to a developmental status. Despite reasonably successful during the preceding 6 weeks, this decision was made because of tactical, logistic and technical problems involved in its use.
23April45 --PB4Y Privateer's launched two Bat glide bombs against the enemy shipping in Balikpapan Harbor, Borneo, in the first combat employment of the only automatic homing bomb to be used in World War II.
The Japanese Baka rocket/jet piloted suicide bomb was unstoppable once launched. However, the mother aircraft, a Betty bomber, was extremely vulnerable.
Photoelectric Fuse for bombs and rockets and Radio Controlled Fuses for anti-aircraft shells. Naval research efforts were concentrated on the proximity fuse.
Aerial Ram. The navy's Gorgon project initiated 19July43 was to develop a radio control jet missile to ram aircraft. The AAF toyed with the idea to reinforce the wings and body of a rocket airplane so that it could survive ten collisions to cut through the light aluminum tail of enemy bombers. Northrop XP-79 Flying Ram
Aerial Torpedo. The idea was to fly a radio controlled airplane bomb into an enemy formation and explode.
Radio Controlled Bomber Drone. Project Aphrodite. The idea was to pack an aged
bomber with 10 tons of explosives and fly it into the impregnable submarine pens on the
French coast. A pilot was required to get the bomber airborne and trimmed
so that a controlling plane could fly it to the target. The first plane
exploded over England before the pilot had bailed out. The pilot was Navy
Lt Joseph Kennedy, eldest son of that family, who was being groomed for the
presidency, a post later held by the second son, John F. Kennedy.
Sep 3, 1944 --A pilot took off in a torpex-laden drone Liberator from an airfield in England, set radio control and parachuted to the ground. The PV controlling the Liberator's flight, sought to hit submarine pens on Helgoland Island; however, he lost view of the plane in a rain shower during the final alignment and relying only upon the drone's television picture of the terrain hit the barracks and industrial area of an airfield on nearby Dune Island.
TV Guided Drone. A month-long test was conducted in Oct 1944 in the Treasury Islands using television controlled TDR drones of which 2/3 reached the target area and 1/3 hit their targets.
Armor, Fuel Tanks. By Pearl Harbor, all new U.S. aircraft were equipped with protective armor for the pilot and self-sealing fuel tanks. This was learned from the experiences of the Battle of Britain where a single bullet could disable or flame a Spitfire or Hurricane. The Zero had no such amenities, not even radio for the pilot; parachutes were not carried until the Solomons campaign.
Escort Carriers. The Long Island (AVG-1) was commissioned 2 June 1941. By the end of the war, 134 were completed. Thirty-eight were transferred to England as lend lease. These carriers were built on merchant hulls, accompanied convoys and filled in the gaps left in maritime surveillance from land based planes so as to make submarines vulnerable in every part of the ocean. Many saw ferry duty, the Long Island delivered the first Marine fighters to Guadalcanal to participate in the Battle of Eastern Solomons. Escort carriers started to arrive in the Pacific with the Nassau (ACV-16) and Altamaha (ACV-18) October 1942. Scores were in place during Okinawa. Two hundred carriers of all types were planned to participate in the invasion of Honshu in 1946 including those from the Atlantic.
Radar. Radar was under development by all sides from the very first. The various forms of radar rapidly evolved in performance, size and reliability for various uses: land based, ship based, aircraft control, fire control. The number and quality of installations was not uniform and the model of the radar in use varied by date. The U.S. got a jump start on radar from the British developments during their war-accelerated experience in conferences held starting Aug 1940. The Yagi antennae was named for Japanese radar pioneer, Dr. Yagi. Although the Japanese had been the first to develop radar among the major combatants, they were the last to develop this device for military purposes. It was spring of 1944 before most Japanese ships were equipped with the equivalent of a 1942 U.S. radar.
Enterprise (CV-6) reported successful use of radar for detecting and controlling airplanes to a range of 100 miles in a 5-month trial, 28Mar41, and the decision was made to include a radar room in all new carriers. Nineteen ships, including ships on both coasts, were equipped with the earliest CXAM radar by Pearl Harbor, although not all were operational. Five hundred sets were ordered and ships were upgraded as they came in for overhaul. The early ship-borne surface search radar, SC, had a reliable range of ten miles and was replaced with the improved SG and SK models with a PPI display.
[The radar of then was nothing like what we think of as radar today. Radar was interfered with by every bit of natural atmospheric disturbance. Even simple radio reception in the tropics was chancy. Early radar equipment was super sensitive to shock and often failed as soon as combat started. I was a radarman on the last active destroyer escort and she still had some late WW2 era air search radar. It was an oscilloscope of wiggly lines that had to be pointed directly at the target with a hand crank. Compared to our late 1950s state of the art surface search radar, that air search gear was worthless. Now, imagine the condition of radar at the beginning of the war, 16 years earlier. - ed]
The Battles of Coral Sea and Midway were fought at distances in excess of air control radar range.
The two picket destroyers at Salvo Island, Aug 1942, had old SC radar that did not detect the Jap fleet. The only ship with SG radar was at the opposite end of the line from where the attack came.
Helena (CL-50) had the only surface radar at the First Battle of Guadalcanal, Nov 1942, which detected the Japanese battleships only 18 minutes before visual sighting in a night battle.
Airborne radar entered the fleet later with only one plane from each bomber
squadron was so equipped. The first airborne radar was
on a TBF and a SBD aboard Saratoga, 19Oct42.
The first kill by a radar-equipped night fighter of the Pacific Fleet came a year later, 31Oct43, operating from Munda, New Georgia, destroyed a Betty during a night attack off Vella Lavella.
Proximity Fuse. The proximity fuse was a radio transmitter/radar that detected an object in its path. When the object was close enough, about 30 feet, the fuse would go off. Before the proximity fuse, the range to the target had to be estimated and that range dialed into the shell. This was difficult against a maneuvering attack aircraft. The trick to get the tiny radios rugged enough to withstand firing from an anti-aircraft gun. The success of the proximity fuse was confirmed with tests aboard Cleveland (CL-55), 12 Aug 42, which downed three drones with four shots from 5" dual purpose guns. The fuse was ordered into mass production. The first combat use of the proximity fuse was by the Helena (CL-50) off Guadalcanal, 5Jan43. The proximity fuse was such a valuable secret that it was forbidden to be used over enemy territory until late in the war in case the enemy found a dud and become aware and possibly reproduce the technology or develop a countermeasure.
Refueling at Sea. Neutrality Patrols in the Atlantic of 1940 were typically of 14 days and 4,400 miles at patrolling speed. Distances in the Pacific were a step larger. The first months of the Pacific war saw problems in the relief of Wake Island and successes when Enterprise raided Marcus on a 25 day trip and escorted Doolittle for 17 days in Japanese waters at combat speeds. Fleets of both sides would typically sail to the Solomons from Rabaul and Nouumea and return to resupply with infrequent encounters. Refueling-at-sea techniques allowed replenishment of oil, stores and ammunition and whole U.S. fleets remained at sea, in combat, for weeks at a time.
JATO. Jet Assisted Take Off means rockets are attached to a plane to help it take off and reach flying speed from a short runway or with a heavy load. Successfully tested as early as 26May42.
400 mph Fighters. We often revel in the fact that by mid-1943 the US Navy had finally introduced the F6F Hellcat (380 mph) that was superior to the Mitsubishi A6M Zero fighter (346 mph). When the Japanese saw that the war would be protracted, they proceeded to develop advanced fighters to replace the Zero. The A7M "Sam"(391 mph) came too late for the Japanese Navy. The Ki-100 too late for the Army. Few of either saw combat because of destruction of Japanese industrial capability by bombing, and because of the Japanese policy to use up the older airplanes as kamikaze and conserve the newer conventional and advanced types for the "final battle" - the inevitable defense of the home islands from invasion. The J7W Shinden canard interceptor flew 3Aug45 was estimated at 466 mph. Of course, the Allies had upgrades in the pipeline as well; the F8F Bearcat (421 mph) entered squadron service 21May45. Jets exceeding 500 mph were in flying prototype stage.
MAD. Magnetic Anomaly Detection was successfully tested 21Oct 1941. This was used by an airplane to reveal the magnetic field created by the metal in a submerged submarine to allow an attack with depth charge or torpedo. The first detection of a submerged enemy submarine by the use of MAD gear was made by PBY Catalinas on a MAD barrier patrol of the approaches to the Strait of Gibraltar 28Feb44.
The practicability of using a radio sonobuoy in aerial anti-submarine warfare was demonstrated in an exercise conducted off New London by the K-5 blimp and the S-20 submarine on 7Mar42. The buoy could detect the sound of the submerged submarine's propellers at distances up to three miles, and radio reception aboard the blimp was satisfactory up to five miles.
Navy ordered 1,000 expendable radio sonobuoy's and 100 associated receivers 28Oct42.
LST - Landing Ship,Tank. When the Dieppe raid proved that a defended port could not be captured from sea and that landings of material had to be done "over-the beach" the LST was invented to ground on a beach, drop a ramp and let tanks and other rolling stock offload on (nearly) dry land. 1,052 were built.
Brodie. LST launched Piper Cub (OY-1) observation planes - used at Anzio, Iwo Jima and Okinawa.
The German Me-262 first flew 18July41. It could have been ready as a fighter in the summer of 1943, but Hitler personally saw a better use as an uninterceptable bomber with which to attack London. By the time the bomber version was ready, the allies had occupied that part of Europe within range of the fuel hungry jet bomber. It was finally introduced as a fighter July 1944 with 1,830 built and proceeded to take an unacceptable toll on daylight B-17 formations. The U.S. had air superiority and destroyed the Me-262 on the ground that they could not stop in the air.
The British Gloster Meteor flew 5Mar43 and entered combat over England on 4Aug44 when two destroyed German V-1 ramjet buzz bombs on the same day. The Meteor entered squadron service on the continent 20Jan45. The de Havilland Vampire, the first single jet aircraft, flew 29Sep43 and entered service in 1946.
The first U.S. jet fighter design, Bell P-59 Airacomet, flew 1 Oct 42
with 50 delivered in 1943-44. Before the war ended, the improved P-83 flew 25 Feb 45.
The Lockheed P-80 Shooting Star turbojet fighters first flew 8Jan44 and two were in Italy
for operational evaluation (not combat) when the war ended. A contract for
5,000 was curtailed with the end of the war, although more than that number of
the trainer version alone (T-33) were built later. The Shooting Star was the
front line fighter in the early days of the Korean War until the MIG-15 was
The Navy contribution included turbojet engine research at U of Iowa, 29Feb40 and a contract awarded 30June41 to Northrop . The two-engine Ryan FR-1 "Fireball had a prop in front and a jet engine in back, flew July 1944, with 66 delivered before VJ day. Orders for prototypes were placed 7Jan43 for the McDonnell FD Phantom which flew 26Jan45; On 1Jan1945 orders were placed for the North American FJ-1 Fury (flew 27Nov46) and the Vought F6U Pirate (flew 2Oct46). The Fury saw carrier service during Korea.
The Japanese Nakajima Kikka was a smaller version of the German Me-262 twin jet fighter. It flew 7Aug45, one day after Hiroshima.
Guided Missiles. The development of a rocket-powered surface-to-air guided missile for the Navy was awarded to Fairchild for 100 experimental Larks on 21Mar45.
In a crash program to counter the Japanese Baka (suicide) bomb, the Navy authorized development of Little Joe, a ship-to-air guided missile powered with a standard JATO unit on 10May45. Little Joe made two successful flights 20July45.
Suicide, "Special Attack", Kamikaze. See Suicide Details.
Oct 1944, off Leyte in the Philippines, Japanese Kamikaze pilots, in the first planned suicide attacks of the war, hit the escort carriers and sank the St. Lo and damaged thirteen other escort carriers.;
The Japanese Kamikaze removed ships at the rate of more than one a day from the U.S. fleet off Okinawa, 6Apr45--28May45. The Japanese expended some 1,500 aircraft, principally against naval forces: twelve carriers were hit along with 250 other types. About 1 in 5 hit a target. A total of 30 ships were sunk and 350 damaged in ten months of activity.
In addition to Kamikaze aircraft, there were explosive packed Kamikaze motor boats, suicide torpedoes, even suicide swimmers who took several gunboats out of action in the final months of the war.
Atomic Bomb. See Attacks
Helicopter. The Sikorsky VS-300/R-4,
was tested for convoy and rescue work.
24July42. Four were ordered 24 July 1942.
11Apr43. Experimental tandem rotor "flying banana" flew .
18Oct43. First of 24 HNS-1 accepted which were later flown by the Navy and Coast Guard.
16Jan44. North Atlantic convoy weather determined to be unsuitable for HNS-1; to be developed for coastal duty.
1 Oct44 . Hydraulic hoist developed for sea rescue.
7 Mar45 . A dunking sonar suspended from an XHOS-1 helicopter was tested successfully.
7 Mar45 . The Piasecki tandem rotor XHRP Rescuer transport helicopter made its first flight.
2 May45. Eleven airmen marooned in northern Labrador were rescued by a HNS-1.
Seaplane Carriers. The Japanese had seaplane carriers that traveled with the fleet to provide aerial reconnaissance. They also had seaplane tenders at advanced bases to service long range multi-engine reconnaissance flying boats. The Japanese were able to effectively specialize the men and equipment between scouting (patient men and long range aircraft) and combat (aggressive men and fast airplanes.)
The U.S. had seaplane tenders to provide patrol planes for advanced bases. However, fleet reconnaissance was performed by the same combat planes and pilots that were expected to return, rearm and then attack whatever they found. This caused fatigue on the pilots and planes. (Until mid-1941 pilots had to train in all three specialties: fighter, dive bomber, and torpedo plane). Fletcher introduced the policy of having one carrier assigned to reconnaissance, in rotation, so that all but that one carrier was ready to attack. The carrier on reconnaissance duty would then proceed to recall, reboard, and rearm her aircraft and provide the follow-up attack. This deficiency with fleet aircraft was later satisfied by the introduction of sufficient escort carriers that some were dedicated to reconnaissance, some carriers even specialized for night fighting.
Good Torpedoes. Duds were the bane of American submarines, torpedo bombers, and destroyers. The Asiatic fleet of 29 subs fired 96 torpedoes at the Philippine invasion fleet with no significant hits. Great risk is required by a crew to get within torpedo range and position and to then have the torpedo not go off was tragic. High tech torpedoes had been too expensive to get adequate sea testing -- a problem with the magnetic detonator was not recognized and deactivated until mid'43. Reliable depth holding was another problem: the war torpedo would run ten feet lower than the practice torpedo and, as often as not, pass under a ship. Detonators designed for older torpedoes would fail in new higher speed models. A large percentage had erratic direction ; circling torpedoes were another hazard. At least two of our subs were sunk by their own torpedoes - Tullibee and Tang !
The Japanese had longer range, more powerful, stealthy, and reliable torpedoes that took a heavy tool of Allied ships, specially from the aggressive destroyer fleet. At Tassarago, Japanese destroyers took out a U.S. task force of four heavy cruisers.
Amphibious Assault Ships
Shinshu Maru was completed in 1935 and modified in 1936 to include a floodable well dock. She was the world's first ship specifically designed to carry and launch landing craft. She introduced stern and side gates to launch landing craft for the 2,200 soldiers she carried. She demonstrated the advantages of the concept at the invasions of Shanghai, Malaya and Java.
Landing craft depot ship and escort aircraft carrier.
Akitsu Maru completed January 1942 and her sister ship Nigitsu Maru completed March 1943. The ships were fitted with a flight deck and elevator above the hull and carried landing craft, troops, supplies, and 8 aircraft on deck and up to 30 below.
Submarines carrying aircraft on deck and launched by submerging were tired by both Germany and England in WWI.
About half, 42, of Japan's initial fleet submarines carried a single scout aircraft used for reconnaissance of Allied bases from Pearl Harbor to Zanzibar. One fire-bombed a forest in Oregon, twice, fortunately, during a rainy season.
Ship Borne Aircraft.
The Japanese had seaplane carriers that could carry assault troops and tankers that launched seaplane fighters and bombers..
The British could catapult Spitfires from merchant ships that either crash landed near a ship or flew on to land based airfields.
It would make sense to have assault ships with flight decks to launch aircraft to airfields in support of the troops. (predecessor to the LSD, LSH of today)
Tankers with a flight deck to provide convoy AS and AA escort.