Three different kits were tested. The first, and that which eventually was adopted, was very much like the TK-1. Among the armament features installed in the UH-IE as a result of Bell's common manufacturing process with the Army versions were attaching points to which the Marines fastened a platform on each side of the aircraft. Two electrically fired M-60C machine guns were mounted on each platform, unlike the TK-1, which had guns only on one side. Two bomb racks were bolted on to the bottom of the platforms. Normally 2.75-inch rocket pods were suspended from the bomb racks, though other items could be carried.

  A simple ring and post type of sight was provided which swung up to the top of the cockpit when not needed. To provide the forward point of the sight, a small piece of black tape was placed on the windshield. While the sight seemed crude, it was effective and simple. "Many more elaborate types of sights exist," HMX-1 reported, "but all require major modification of the UH-IE cockpit, introduce added maintenance requirements, or block the pilot's vision."

  The kits, dubbed TK-2, were assembled by the Overhaul and Repair Activity, Jacksonville, Florida, under the technical direction of HMX-1 and the Marine Corps Landing Force Development Center (MCLFDC). A total of 15 were made.

   Test firing at NAS, Patuxent River revealed only minor problems. The most serious was that the expended cartridge links ejected from the left guns could endanger the tail rotor. (The same problem was one of the reasons the UH-34 had no guns on the left side.) The guns were slightly repositioned and later deflector plates were added.

  This apparently solved the ejected link problem. However, on the last day of test firing, several additional nicks in the tail rotor were received. It was decided, in view of the time element, to go ahead with the fabrication of the other kits and continue efforts to solve the ejection problem after the kits were completed and delivered to Fleet Marine Force units. The alternative was to hold up delivery to a deploying squadron."

  On 15 January 1965 the completed armament sets were shipped to VMO-6 at Camp Pendleton. Once in- stalled on the UH-lE’s, they were an immediate success. So much so that on 31 March, CNO requested BuWeps to provide kits for 33 more aircraft. Delivery was promised in July.

  Simultaneously with the development of this TK-2, HMX-1 was experimenting with other kits. Two General Electric .50 caliber SM-14 gun pods were evaluated "with excellent results, providing primarily greater effective range." The added weight made the heavier machine guns suitable only for specialized missions.

   Also tested were two Stoner 63 machine gun pods on temporary loan from the U.S. Air Force. The installation proved unsatisfactory for the UH-IE.

   In addition to the rockets and machine guns mounted on the sides of the helicopter, tests were con- ducted on a rotating turret mounted below the nose of the aircraft. The Emerson Electric TAT-101 turret contained two M-60 machine guns and could be aimed and controlled by the pilot.'14 Beginning in April 1967, UH-lE's were modified to incorporate the turret. A total of 94 kits were purchased. By April 1972, other armament conversions were available which were more suited for the task, and the TAT-101 was removed from those aircraft in which they were installed.

   While the TK-1 on the UH-34 was undergoing final testing at HMX-1 and efforts were under way to have approved a similar kit for the UH-IE, General Krulak at FMFPac sent CMC his estimate of the results, which could be expected. "The proposed arming of the UH- 34 will not provide equivalent protection to replace U.S. Army UH-IB's." The TK-1s, however, should be provided and "the assignment of Marine UH-IE helicopters to the 1st Marine Air Wing be expedited for employment in armed escort as required."  As soon as the pilots at Pendleton finished training, six of the armed UH-lE's were shipped in April to Futenma. These six aircraft of Lieutenant Colonel George Bauman's VMO-2 arrived at Da Nang on 3 May 1965. They immediately began to take over the role of escorting the Marine assault troop helicopters.

   The introduction into Vietnam of Marine armed helicopters did nothing to still the proponents or opponents of the concept. The situation was not helped by a controversy, which during 1964 was becoming increasingly public, between the Air Force and the Army over their respective roles. For airborne fire- power, the Army placed almost total reliance on its armed helicopters. The Air Force held that only its fixed-wing aircraft were suitable for close air support and helicopter escort.

   The Marine Corps occasionally got dragged into the controversy between the two other services. General Greene made a speech at the National Press Club in Washington, D.C. on 26 March 1964. In it, he once again stated his position on armed helicopters. Press accounts, unfortunately, were written stressing that the "Marines Join Air Force in Opposing Helicopters Ground Support"

   He had made no such statement. What General Greene told the reporters was the same thing he had been telling and would continue to tell the Marines-

   “This service [armed helicopters in South Vietnam has been carried out under peculiar circumstances which has led many people to question the Marine Corps' position and has resulted in some misunderstanding of it.   The special situation in South Vietnam has not caused us to modify our belief .  In South Vietnam, Marine Corps tactical fixed wing aircraft have not been available because of political considerations.”

   He summed up. "We consider this capability (armed helicopters] must be complementary, rather than competitive with the primary fire support provided by fixed wing aircraft.

   Marine attack aircraft, after they were introduced into Vietnam, were used to protect and escort the assault helicopters. So were armed helicopters. Each in its way performed a vital mission. Throughout the conflict in Vietnam, the Marine Corps continued to maintain a balance of weapons which were capable of performing anywhere in the world under almost any conceivable circumstance. The armed helicopter and fixed-wing attack aircraft were just two of them. Much of the credit belongs to General Greene. He, at least, had not forgotten the lessons of previous wars. ("Marines and Helicopters 1962-73" Lt Col. William R. Fails   USMC")