During the interwar years, Marine Corps officers who spent World War I fighting alongside U.S. Army and foreign forces in the trenches of the Western Front, sought to return the Corps to its seagoing roots. With an eye towards a future war with Japan, Marine Corps tactics of the 1920s and 1930s focused on amphibious operations, the emphasis on this element of warfare bearing fruit during World War II with the successful island-hopping campaigns in the Central and South Pacific.
The end of the war brought a reevaluation of tactics. With the advent of atomic weapons, it was believed that vast invasion fleets floating off a beachhead disembarking troops in landing craft were highly vulnerable to attack. Thus, the Marine Corps turned to alternative methods of putting troops ashore, the platform on which they focused their attention being the helicopter. The result was the issuance of the pamphlet Amphibious Operations—Employment of Helicopters (Tentative) by the Marine Corps Schools at Quantico, Virginia, in 1948. Of course, the success of “vertical assault” depended upon the development of a rotary wing platform that could execute the mission. The wartime HNS Hoverfly, which in the hands of Coast Guard aviators had proven the value of helicopters in the medical evacuation role, was not capable of transporting troops and their equipment in adequate numbers to influence a land battle. The HO3S, the first of which was delivered to Marine Experimental Helicopter Squadron (HMX) 1 in 1948 for testing and evaluation purposes, demonstrated this fact during an operational deployment in Mary 1948. Flying from the escort carrier
Palau (CVE 122), it took five HO3Ss a total of 35 flights to deliver just 66 men and several hundred pounds of equipment from ship to shore during an amphibious exercise in North Carolina.
The introduction of the HRP, whose canvas-covered fuselages was angled in such a way that the airplane resembled a “Flying Banana,” brought a helicopter more capable of serving as a troop transport with room to carry 10 men. Yet, its fragility limited it to a non-combat role, and when the Korean War erupted in June 1950, the Marine Corps did not possess a helicopter able to truly influence a battleground by moving a sizeable number of troops into a landing zone via helicopter.
This changed on
September 2, 1951, with the arrival of Marine Helicopter Transport Squadron (HMR) 161 at the port of Pusan, South Korea, on board the escort carrier
Sitkoh Bay (CVE 86). The squadron came equipped with the Sikorsky HRS-1, a design whose ruggedness mirrored the landscape over which it would fly in Korea. With a top speed of 101 miles per hour generated by a 550 horsepower Pratt & Whitney R-1340 engine in a nose compartment accessible through clamshell doors, the HRS-1 was designed to accommodate 8 troops. It did not take long for the squadron to become operational. Eleven days after arriving in country, HMR-161 commenced Operation Windmill I in support of the First Marine Division, airlifting supplies a distance of 7 miles from a base camp to a forward operating area. This marked the first test of the capabilities of transport helicopters, and included 28 flights that delivered 18,848 pounds of supplies and evacuated 74 seriously wounded Marines. Later, during Operation Summit, HMR-161 proved its ability to airlift human cargo. On September 21st, 12 helicopters carried 224 combat troops and some 18,000 pounds of equipment a distance of 14 miles to occupy Hill 884. The momentous days marked the dawning of a new era warfare in which the helicopter became an integral element in support of ground operations, a role that continued in Vietnam and holds true today in Iraq and Afghanistan.
Pictured above, HRS-1 helicopters of HMR-161 pictured during operations in Korea.
Other Significant September Events in Naval Aviation History
September 2, 1925- Crash of the rigid airship Shenandoah (ZR 1)
September 23, 1931- XOP-1 autogiro lands on the carrier Langley (CV 1)