This Naval Helicopter History Timeline is sourced using historical data and pictures from “THE NAVAL HELICOPTER-HIGHLIGHTS IN NAVAL HELICOPTER HISTORY,” written by CAPT Vincent C. Secades USN (Ret), Published by Naval Helicopter Association, Coronado, California, 2nd Edition June 2012.
400BC |1940 | 1950 | 1960 | 1970 | 1980 | 1990 | 2000 | 2010
NAVAL HELICOPTER HISTORY TIMELINE 1950 till 1960
Navy purchases Ten H-19s, Navy Designation HO4S-1
April 28, 1950. – The Navy purchased ten H-19s, Navy designation HO4S-1, for evaluation in the helicopter ASW project. A total of 129 
HO4Ss were delivered to the Navy between August 1950 and January 1958. They were used by the HS Squadrons in their ASW configuration. The HO4S was the first antisubmarine helicopter to operate from aircraft carriers. The utility version was used by the HU squadrons, by the Air Stations, and as advanced trainer in HTG-1, Ellyson Field, Pensacola.
3500 Mile Helicopter Flight in 62.5 Hours
July 1950–Distance: 3.500 Miles (5.632 Km) in 62.5 hours
Route: from Boston Squantum Naval Air Station Maryland to North Island Naval Air Station San Diego California
Crew:
Pilot: Lt. Conrad Larson Pilot
Crewman: AD1. Gerald Dwight.
VMO-6 Equipped with the HO3S Helicopters
August 3, 1950. – Elements of VMO-6 equipped with the HO3S helicopters began operations in support of the First Provisional Marine Brigade in the vicinity of Changwon, South Korea. The helicopters were put to use immediately delivering rations and water to the troops on a mountain, and evacuating casualties..
HO3S Evacuated a cCasualty from a Korean Firefight
August 4, 1950. – An HO3S evacuated a casualty from a firefight along the Pusan perimeter; five more were evacuated the next day. This event marked the beginning of one of the most dramatic and important uses of the helicopter in the Korean War. Helicopter medevac would revolutionize the triage of battlefield casualties and significantly decrease the mortality rate.
Flight of a Helicopter under Automatic Control was Made
August 7, 1950. – Flight of a helicopter under automatic control was made at Mustin Field, Philadelphia using an HO3S-1 helicopter equipped with a single axis automatic pilot. Successful test of this instrument confirmed the feasibility of a helicopter automatic pilot which was being developed under the leadership of L. S. Guarino at the Aeronautical Instrument Laboratory, Naval Air Material Center.
Navy Awards Kaman Contract for the HTK-1Helicopter
September 1950. – The Navy awarded Kaman a contract for a trainer, the HTK-1, an improved K-225 design. The first HTK-1 flew in 
April 1951. A total of 29 HTK-1s were delivered to the Navy between November1951 and October 1953. They were used as utility helicopters at Naval Air Stations all over the world before they were sent to Pensacola, where they were redesignated TH-43As and used as trainers until 1957.
HO3S-1 Helicopter Successfully Flown with Automatic Pilot
September 23, 1950-An HO3S-1 helicopter, equipped with an automatic pilot developed by the Aeronautical Instruments Laboratory, was successfully flown with three axis automatic control at Mustin Field, Philadelphia.
Ellyson Auxiliary Landing Field (ALF) was Established.
December 3, 1950. – Ellyson Auxiliary Landing Field (ALF) and its main tenant, Helicopter Training Unit One (HTU-1) were established. HTU-1 took over the training of helicopter pilots from HU-2, based at NAS Lakehurst. HTU-1 used the Bell HTL-4 (TH-13) and Hiller HTE-1/-2 as primary trainers. Advance training was conducted in the Sikorsky HO3S-1 and the Piasecki HUP-2. The HTEs were retired by late 1952.
First Helicopter Pilot Medal of Honor
July 3, 1951. – Late in the afternoon, LTJG John K. Koelsch, serving with a HU-2 detachment embarked on an LST off the coast of Wonsan, North Korea, launched to rescue a Marine F4U pilot that had bailed out 35 miles inside enemy territory. Without RESCAP protection due to poor visibility, LTJG Koelsch located the survivor and began hoisting him aboard when enemy fire downed his HO3S-1 helicopter. LTJG Koelsch, his crewman, AM3 George M. Neal, and the F4U pilot, CAPT James V. Wilkins, survived the crash and hid in the mountains, evading enemy patrols for three days. Then they began to slowly make their way down to the coast. Six days later they reached a coastal village and hid in a hut. They were captured the next day. In the months that followed LTJG Koelsch refused to submit to his interrogators and was tortured mercilessly. His fortitude, personal bravery, and consideration to others were sources of high morale and inspiration to his fellow prisoners. John Koelsch died of malnutrition and dysentery in a North Korean POW Camp on 16 October 1951. On August 3, 1955, LTJG John Kelvin Koelsch was posthumously awarded the Medal of Honor for his actions in Korea. He was the first helicopter pilot to be awarded the Medal of Honor. AM3 Neal was awarded the Navy Cross.
Marines Receive New Sikorsky S-52 Utility Helicopter, Navy Designation HO5S-1
September 1951. – The Marines began to receive the new Sikorsky S-52 utility helicopter, Navy designation HO5S-1. It was used for medevac, gunfire spotting, reconnaissance, and general utility work. The HO5S-1 was handicapped by being underpowered. In spite of this handicap, it was used extensively by VMO-6 in Korea. After the war the HO5S-1 was used as a trainer by the Marines in New River, NC. It was retired from service in the late 1950s.
Marine Helicopter Transport Squadron 161, Equipped with HRS-1s, arrived Pusan, Korea
September 2, 1951–Marine Helicopter Transport Squadron 161, equipped with HRS-1s, arrived Pusan, Korea, aboard Sitkoh Bay and flew ashore prepared to perform transport, assault, and supply missions for the First Marine Division. On 13 September it began its support of the First Marine Division with Operation Windmill I. In this initial combat test of transport helicopter capabilities, the squadron lifted one day’s supplies for the First Marine Battalion on a 7-mile carry from its base to the forward area.
Helicopter Antisubmarine Squadron One (HS-1) Established at NAS Key West
October 3, 1951. – Helicopter Antisubmarine Squadron One (HS-1) was established at NAS Key West, FL. After the squadron establishment, LCDR Graham, who led the seven-year-long development effort that made this event possible, reported to NATC, Patuxent River for duty as a helicopter test pilot.
Marines Using HRS-1 Helicopters From HMR-161 Insert Nearly 1,000 Troops
.October 11, 1951. – Marines wrote a new chapter in military history. Using HRS-1 helicopters, HMR-161 aircrews inserted nearly 1,000 Marines atop a 3,000-foot mountain near the front lines. Over a period of six hours a dozen HRSs flew a total of 156 sorties. The success of this operation marked the first implementation of the vertical assault concept.
Navy-Sponsored Kaman K-225 Fitted with a Boeing YB-502, 190 shp Turbine Engine
December 12, 1951. – In a Navy-sponsored technology program, a Kaman K-225 fitted with a Boeing YB-502, 190 shp turbine engine performed its maiden flight. This was the first gas turbine-powered helicopter in the world. With the advent of the gas turbine engine, the helicopter finally found its ideal power plant.
Helicopter Anti-Submarine Squadron Two (HS-2) Golden Falcons Established at ALF Ream Field, Imperial Beach, CA
March 7, 1952. – Helicopter Anti-Submarine Squadron Two (HS-2) was established at ALF Ream Field, Imperial Beach, CA. HS-2 was the first antisubmarine warfare helicopter squadron on the West Coast. Initially, it deployed small detachments flying the Sikorsky HO4S-2 helicopter. The HO4S was replaced by the HSS-1 (SH-34J) early in 1955.
HS-3 was Established
June 18, 1952 – HS-3 was established at Naval Air Facility, Elizabeth City, NC.
HS-4 was Established
June 30, 1952 — HS-4 was established at ALF Ream Field, Imperial Beach Ca.
Navy Awarded Sikorsky a Contract for a Prototype, Designated the XHSS-1
June 30, 1952. – Looking for a more capable helicopter to replace the HO4S in the ASW role, the Navy awarded Sikorsky a contract 
for a prototype, designated the XHSS-1. The XHSS-1 first flew on 8 March 1954. Production deliveries started in early 1955. The Navy accepted a total of 385 HSS-1s, the last aircraft being delivered in April 1966. The HSS-1 served with the Helicopter ASW squadrons until replaced by the HSS-2 (SH-3A) in 1961. In 1962 all military services adopted the USAF aircraft designation system. The UH-34D, the utility version of the HSS-1, replaced the HO4S-1 as the advance helicopter trainer in HT-8, Ellyson Field, Pensacola, in mid-1963.
VX-1 Pilots Flying a HRP-1 Helicopter Demonstrates Feasibility of Helicopter Towing Minesweeping Equipment
November 18, 1952. – VX-1 pilots flying a HRP-1 helicopter off the coast of Panama City, Florida, demonstrated the feasibility of using a helicopter to tow minesweeping equipment. This was the first of a series of tests.
Navy Sponsor in 1953 Kaman Aircraft Development of Remote-Piloted Helicopter Drones
March 1953. – Under Navy sponsorship, in 1953 Kaman Aircraft began development of remote-piloted helicopter drones. In the spring of that year an HTK-1K, nicknamed the “Yellow Peril,” began remote-controlled flight-testing. These tests continued through the mid-1950s, always carrying a safety pilot in the cockpit. On 23 May 1957 a drone HTK-1 helicopter, with a safety pilot onboard, operated by remote control from the small deck of USS Mitscher (DL-2) underway in Narragansett Bay. On 30 July 1957, in a test conducted at the Kaman plant in Bloomfield, Connecticut, a modified HTK-1 drone completed its first unmanned flight.
HS-2 First ASW Squadron to deploy to Westpac
April 1953–HS-2 First ASW Squadron to deploy to Westpac.
Kaman’s XHOK-1 Prototype First Flight
April 21, 1953. – Kaman’s XHOK-1 prototype performed its first flight. It proved to be a very capable helicopter. Deliveries to the 
Marines started that same month. A total of 81 HOK-1s powered by a 600hp R-1340-48 engine were assigned to the VMO squadrons. The Navy bought 24 HUK-1s, the Navy version of the HOK-1, powered by the R-1340-52 engine. The last HUK-1 was delivered in December 1958. They were initially assigned to the helicopter utility squadrons.
The Marine Corps XHR2S-1 Flew for the First Time.
December 18, 1953. – The XHR2S-1 flew for the first time. This was the first twin-engine helicopter built by Sikorsky. It used two Pratt and Whitney R-2800-5, 2100 hp radial engines and a five-blade main rotor. The contract, signed on 9 May 1951, called for a helicopter capable of transporting twenty fully loaded soldiers. Deliveries to HMX-1 began in July 1956. Between 1956 and 1959 the Marines accepted 59 units. The re-designated CH-37s served with HMR (M)-461, based at MCAS New River, NC, and HMH-462, based at MCAF Santa Ana, CA. They were retired from service on both squadrons in 1966, being replaced by the much more capable CH-53As.
Kaman Fitted an Experimental HTK-1 with Two B-502 Turbines
March 1954. – Kaman fitted an experimental HTK-1 with two B-502 turbines, this becoming the world’s first twin-turbine powered helicopter.
First Tilt-Rotor V/STOL
July 6, 1954. – In 1945 Robert Lichten, a Platt-LePage Aircraft Co. engineer, and Mario Guerierri, a Kellett Aircraft Co. engineer, teamed up and formed Transcendental Aircraft. They developed the first tilt-rotor V/STOL convertiplane in the U.S., the Model 1-G, a 1,750-pound aircraft with two 17-foot diameter rotors powered by a 160-hp engine. After a long and difficult ground-testing period, which included an accident in 1951, the Model 1-G finally achieved free flight on 6 July 1954. It achieved 80 degrees conversions in December of that year. On 20 July 1955, after logging 23 hours, the Model 1-G crashed in the Delaware River and was lost.
The Flying Platform
January 21, 1955–The Flying Platform, a one-man helicopter of radical design, made its first flight at the Hiller plant in Palo Alto, Calif. Although the flight occurred during ground tests and was therefore accidental, it was successful in all respects.
First Bell XV-3 Tilt-Rotor Prototype Rolled Out on 10 February 1955
August 11, 1955. – The first Bell XV-3 tilt-rotor prototype rolled out on 10 February 1955, and first hovered on 11 August of that 
year. It featured two 23-foot diameter three-bladed rotors mounted on long masts. After two months of testing, the aircraft crashed. A second prototype with shorter masts and two-bladed rotors followed. After a series of wind tunnel tests and hover tests, the XV-3 made its first transition to forward flight on 17 December 1958. Seven years of exhaustive testing followed. After 375 wind tunnel and ground test hours, 250 test flights (125 flight hours) and over 110 full conversions, the XV-3 firmly established the feasibility of the tilt-rotor convertiplane.
Bureau of Aeronautics issued instructions describing new color schemes
February 16, 1955–The Bureau of Aeronautics issued instructions describing new color schemes that would be used on all new Navy and Marine Corps aircraft beginning 1 July 1955 and applied on all currently operating aircraft within the next 2 years. The familiar sea blue was changed to light gull gray on top and glossy white below for carrier aircraft, all over seaplane gray for water based aircraft and all over light gull gray for helicopters. Bare aluminum was retained for utility types and land plane transports, the latter having in addition a solar heat reflecting white top. Orange-yellow remained the color for primary trainers but the advanced trainer scheme was changed to international orange and insignia white. Other changes were olive drab above and glossy white below for land observation types and a combination of orange-yellow, engine gray and insignia red for target drones and target tow aircraft..
CVHE for Escort Helicopter Aircraft Carrier
May12, 1955–The classification of naval vessels was revised to provide the designation CVHE for Escort Helicopter Aircraft Carrier and CVU for Utility Aircraft Carrier. The carriers were re-designated 1 month later.
USS Thetis Bay CVE-90 Re-Commissioned CVHA-1, First Helicopter Assault Carrier
July 20, 1956. – After completing the conversion to the new mission at the San Francisco Naval Shipyard, USS Thetis Bay, the old CVE-90, was re-commissioned as CVHA-1, the first helicopter assault carrier in the U.S. Navy. On May 28, 1959, while on her first deployment to WESTPAC, Thetis Bay was redesignated Landing Platform Helicopter Six (LPH-6). She carried a Marine Assault Team of about 1,000 combat troops and the helicopter assets to transport them ashore during the vertical assault phase of an amphibious landing.
Transcendental Model 2 Tilt-Rotor Aircraft Completed
October 1956. – Construction of the Transcendental Model 2 tilt-rotor aircraft was completed. With a 250 hp engine and two 18-foot diameter rotors, the aircraft offered greater payload capability. It began flight-testing near the end of the year. The Model 2 could not compete with the Bell XV-3, causing Transcendental to close shop in 1957.
The carrier Saipan with Helicopter Training Unit HTU-1
October 10, 1955–The carrier Saipan with Helicopter Training Unit HTU-1 aboard, left Tampico, Mexico, after a week of disaster relief operations for the inhabitants of the area. During these operations, the helicopters rescued 5,439 persons marooned on rooftops, trees and other retreats, and delivered 183,017 pounds of food and medical supplies, thus earning the commendation of the Task Group Commander and the best wishes of a thankful people.
A Sikorsky HR2S helicopter Sets New Records
November
9–A Sikorsky HR2S helicopter, piloted by Major R. L. Anderson, USMC, at Windsor Locks, Conn., began a 3-day assault on world records, setting three new marks as follows: 9 November, carried a payload of 11,050 pounds to an altitude over 12,000 feet; 10 November, carried 13,250 pounds to over 7,000 feet; and 11 November, set a speed record of 162.7 m.p.h. over a three-kilometer course.
U.S. Marines Began to Receive the HUS-1 (UH-34)
January 1957. – The U.S. Marines began to receive the HUS-1 (UH-34). They used it extensively in Vietnam as troop transport. The Marines also fitted some HUS helicopters with “Temporary Kit One” (TK-1), which comprised two M60C machine guns and two pods with nineteen 2.75-inch rockets each. These improvised gunships did not perform as expected and were quickly phased out. In 1960 NATC conducted tests to establish the feasibility of launching Bullpup air-to-surface missiles from an HUS-1. These tests were completed on 3 June 1960. The program, however, never advanced beyond the test phase. On 18 August 1969 the last Marine UH34D in Vietnam was retired from HMM-362 at Phu Bai.
HS-5 Established
January 3, 1956—HS-5 Established at Naval Air Station Norfolk, Va.
Early Drone Anti Submarine Helicopter (DASH) Weapons System
April 2, 1958. – The Navy awarded Gyrodyne Company a contract to modify its RON-1 Rotorcycle small two coaxial rotors helicopter to explore its use as a remote-controlled drone capable of operating from small decks carrying ASW weapons. Another contract followed on 31 December 1958 to build nine QH-50A (DSN-1) and three QH-50B (DSN-2) ASW drone helicopters for the new Drone Anti Submarine Helicopter (DASH) weapons system. The QH-50As were used as evaluation prototypes for the airborne segment of the system.
HS-9 Established
June 1, 1956—HS-9 Established at Naval Air Station Quonset Point, Rhode Island.
Birth of the Huey Helicopter-1st flight of the Bell XH-40
October 20, 1956– This day in heli history – October 20, 1956: Birth of the Huey – 1st flight of the XH-40.
A Drone HTK-1 Helicopter
May 23, 1957–A drone HTK-1 helicopter, carrying a safety pilot, operated from the fantail of Mitscher (DL 2) in the vicinity of Narragansett Bay. These tests and others, conducted in February off Key West, in which a piloted HUL-1 carried Mk 43 torpedoes in flights to and from the Mitscher, demonstrated the feasibility of assigning torpedo carrying drone helicopters to destroyers and led to the development of the Drone Anti-Submarine Helicopter (DASH) which was later embodied in the QH-50C.
HS-11 Established
June 27, 1957—HS-11 Established as Jacksonville Florida.
The First Pilotless Helicopter Flight was Made
July 30, 1957–The first pilotless helicopter flight was made at Bloomfield, Conn. Built by Kaman Aircraft, under joint Army-Navy contract, the new helicopter was designed on the basis of principles developed experimentally under Navy contract using a modified HTK.
Early Drone Anti Submarine Helicopter (DASH) Weapons System
April 2, 1958. – The Navy awarded Gyrodyne Company a contract to modify its RON-1 Rotorcycle small two coaxial rotors helicopter to explore its use as a remote-controlled drone capable of operating from small decks carrying ASW weapons. Another contract followed on 31 December 1958 to build nine QH-50A (DSN-1) and three QH-50B (DSN-2) ASW drone helicopters for the new Drone Anti Submarine Helicopter (DASH) weapons system. The QH-50As were used as evaluation prototypes for the airborne segment of the system.
Commander in Chief, Atlantic Fleet Forms of a New Amphibious Squadron
October 21, 1958. – The Commander in Chief, Atlantic Fleet, announced the formation of a new Amphibious Squadron composed of USS Boxer (CVS-21) and four LSDs equipped with helicopter platforms. Boxer was being used as an experimental helicopter carrier. She was redesignated LPH-4 on 30 January1959. The newly formed squadron’s mission was to deploy a “vertical envelopment team” of Marine combat troops and helicopters.
The XHSS-2 Sea King First Prototype Performed its Maiden Flight
March 11, 1959. – The XHSS-2 Sea King first prototype performed its maiden flight. The helicopter was especially designed to be 
an all-weather dipping sonar platform. It was equipped with Doppler radar integrated in an automatic approach and hover system. This system made the HSS-2 a significantly safer night ASW operations platform than prior machines. The HSS-2 joined the fleet in September 1961. In 1962, under the new DoD standardized system, the HSS-2 became the SH-3A.
Kaman Began Flight-Testing the First Prototype of the UH-2 Seasprite Helicopter
June 1959. – Kaman began flight-testing the first prototype of the UH-2 Seasprite helicopter. After completing evaluation at NATC, Patuxent River, the Navy began to accept deliveries of the UH-2A and UH-2B models in December 1962, these two models only differing in electronic equipment. The UH-2 was delivered to HU-1 and HU-2 for service with detachments aboard aircraft carriers.