 |
 |
 |
|
|
|
The helicopter was first employed in a mine countermeasures (MCM) role in October, 1950 during channel clearing efforts in the harbor at Wonson, Korea. Mines laid by the North Koreans stalled an amphibious assault for eight days. The U.S. Navy lost 92 sailors on minesweeping ships during clearance operations. The Navy began to employ helicopters as spotter aircraft, searching for mines in the path of the surface minesweepers. HRP-1 flying banana The concept of Airborne Mine Countermeasures (AMCM) was initiated by the Bureau of Aeronautics in 1951, and research and development (R&D) to exploit the capability of the helicopter to participate in MCM operations was significantly expanded. This R&D effort in AMCM continued throughout the Korean and Vietnam conflicts as various helicopters were examined for suitability in the MCM role. Towed moored, magnetic, and acoustic sweep equipment was also developed specifically for the helicopter.  Bell HSL-1 helicopter under tow In 1952, Piasecki HRP-1 flying banana's were tested in Panama city to demonstrate their potential as minesweepers. VX-1, the Navy test squadron at Key West, Florida, also tested Piasecki's new minesweeping equipment aboard the HRP-1. In order to reduce weight on these underpowered helicopters, the fabric skin of the aircraft was removed, and large donut shaped flotation inner tubes were attached to the renmaining framework. The minesweeping trials were fairly successful, even though the aircraft looked quite ridiculous.  Piasecki H-21 helicopter under tow In 1957, the U.S. Naval Air Mine Defense Development Unit was established to develop and evaluate aviation systems, materials, and techniques for mine countermeasures. Among the aircraft evaluated were the Bell tandem-rotor HSL, Sikorsky's S-60 Skycrane with palletized sweep gear, and even the ZPG-1 Airship. The single piston engine Sikorsky HSS-1 Seabat was also evaluated as a minesweeper, but fortunately was never adopted.  Sikorsky S-60 with palletized sweep gear Early in the development of the minesweeping cutter arrays, the equipment was streamed from a surface vessel and towed by the helicopter. Procedures and equipment were designed for the helicopter to take the minesweeping gear from the ship and transfer it to another helicopter to extend the duration of the mission. It wasn't until 1960 that the U.S. Naval Air Mine Defense Unit flew portable sweep gear which enabled the helicopter to operate without the aid of the ship. In 1962, the Chief of Naval operations directed helicopters be converted for MCM development, training and eventual operational deployment. The twin-turbine, tandem rotor Boeing-Vertol HRB-1 or RH-46A was the aircraft of choice. Unfortunately, the U.S. Marine Corps (USMC) had more urgent need for the H-46's, so the Navy turned to the Sikorsky HSS-2, renamed SH-3A Sea King. In 1964, Sikorsky began converting nine SH-3A's to RH-3A's for AMCM.  RH-3A Minesweeping Helicopter The RH-3A, with it's ASW sonar removed, was modified for AMCM. A pivoting towboom and towhook, tension and yaw angle indicators, pilot controlled eletrical rear-view mirrors, second large cargo door on the port side, reinforced cargo floor with access to tow winch below, and two aft observation bubbles were installed. In order to strenghten the helicopter for the stresses it would be placed under during towing operations, the upper forward cabin and transverse fuselage between the cargo doors, aft tub, and the tail wheel were all reinforced. Fuel and oil capacity was also increased by additional tanks installed in the cabin. Tilting seats from the S-64 Skycrane were used to compensate for the extreme nose-low attitude the Sea King developed while towing under tension. The RH-3A towed the MK-101 Vermoor Cutter Array, MK-104 Acoustic Minesweeping System, AN/SPU-1W Magnetic Orange Pipe, and struggled with the MK-105 hydrofoil sled. It also had it's sonar well enlarged to accomodate the primitive AN/ALQ-79 Turtle II mine-hunting sonar. The first RH-3A flew in 1965, with deliveries continuing until 1966. These aircraft were initially stationed at Naval Air Test Center (NATC) at Patuxent River, Maryland and Air Mine Defense Development Unit at Panama City, Florida. NATC pilots flew trials aboard Mine Countermeasures Support Ship USS OZARK (MCS-2) in 1966. The fleet had operational AMCM capability when RH-3A's joined detachments of Helicopter Combat Support Squadrons. In 1967, HC-6 deployed three minesweeping Sea Kings on USS OZARK in the Atlantic and HC-7 deployed three on USS CATSKILL in the Pacific. However, the RH-3A was more of an interim AMCM aircraft. Struggling at the limits of it's engines and dynamic components, the Sea King anti-torque tail rotor was never designed for the flight regime it operated in while towing. With up to 30 degrees nose down attitude while under tension, the RH-3A's tail rotor was past it's design limitations and occassionally failed. This led to increases in the diameter and chord of the tail rotor, as well as improved construction and design. Despite it's limitations and weaknesses, the Sea King proved itself as an AMCM platform until it was replaced. Admiral Zumwalt, Chief of Naval Operations, began Project 60 in 1970. This project was the use of Airborne Mine Countermeasures as the principal means of clearing mines, based upon the sensitivity and sophistication of modern mines which precluded the use of surface minesweeping. The RH-53D Sea Stallion, a version of the CH-53A Sea Stallion was the selected successor as the AMCM platform. However, in an interim measure, the first AMCM squadron, HM-12 Sea Dragons, was formed in April, 1971 using fifteen CH-53A's borrowed from the USMC. As was the RH-3A, the CH-53A was similarly upgraded with AMCM specific enhancements.  HMH-463 CH-53D towing a MOP in Lach Huyen in the Haiphong Roadstead. The end of the Vietnam war brought increased interest in AMCM. The war had ended due in part to heavy bombing and extensive mining. The peace agreement required mine clearance of Vietnamese harbors and rivers. The concept of AMCM finally became realized during the post-war clearance of Haiphong Harbor. Navy and Marine Corps CH-53D Sea Stallion helicopters were the primary clearance force in this clearance operation. HM-12, together with a DET from HMM-165, utilized the MK-105 sled in the deep waters of Haiphong Harbor, while HMH-463 pulled the MOP, and later the triple MOP, in shallow waters. HM-12 embarked their Sea Stallions aboard USS NEW ORLEANS for Operation End Sweep, and on 9 March 1973, triggered the only mine detonated during the operation.  Mine detonated by a MK-105 Hydrofoil sled during Operation End Sweep 9 March 1973 Aircraft Commander: LT C.H. "Skip" Yates, III Copilot: LTjg Ron Kuhurt Crewchief: ATC Kelly In 1974, having received the new RH-53D Sea Stallion, HM-12 was sent to the Middle East to clear the Suez Canal during Operation Nimbus Star. The RH-53D succeeded in not only clearing mines in the water, but also detonated land mines on the banks of the canal. The following year found the RH-53D's clearing the waters around Port Said in Operation Nimbus Stream. The RH-53D had improved engines, air-to-air refueling capabilites, and AMCM modifications. Two new AMCM squadrons were formed in 1978, HM-14 and HM-16, while HM-12 became the training squadron for the AMCM community.  RH-53D Minesweeping in the Gulf of Suez During Operation Intense Look in 1984, HM-14 employed the AN/AQS-14 minehunting sonar for the first time operationally. HM-14 searched for contact mines in the Persian Gulf in 1987 during Operation Earnest Will. During this operation, for the first time since the Korean war, live moored contact mines were swept.  MH-53E Sea Dragon helicopter in a hover The Navy had designed a new larger hydrofoil sled, the MK-166, and realized that even the RH-53D was underpowered to tow it. So in 1982, Sikorsky was awarded a contract to develop a new minesweeper, the MH-53E Sea Dragon. Based on the CH-53E Super Stallion, the first prototype of this three engine, seven bladed MH-53E helicopter was in fact a conversion CH-53E. It first flew in September 1983, and the first production aircraft was delivered to HM-12 in April 1987. It was decided that HM-16 would be disestablished in 1987, and key personnel would be taken to form HM-15 in Alameda, California, the first operational MH-53E squadron. The Naval Reserve received the RH-53D's displaced by the MH-53E's and formed two reserve AMCM squadrons, HM-18 in 1986 and HM-19 in 1989. Though the MK-166 sled was abandoned, the Sea Dragon has proven to be a valuable and powerful AMCM platform. Rated at 25,000lb maximum tow tension, the MH-53E eclipses the RH-53D (15,000lbs) and RH-3A (a mere 8,000lbs). During Operation Desert Shield, HM-14 deployed six aircraft aboard USS TRIPOLI, then moving to USS NEW ORLEANS and USS LA SALLE. Most of the minesweeping missions in the gulf were MK-103 cutter arrays and MK-106 magnetic/acoustic sweeps. Toward the end of Operation Desert Storm the AN/AQS-14 sonar was successfully employed. During this period the helicopters also upgraded to Global Positioning System receivers for minefield navigation. Prior to this, the crews had to depend on less acurate and more complicated systems to determine their position in the minefield. The MH-53E's were usually trailed by SH-3 Sea Kings, SH-60 Seahawks, or UH-1N Twin Hueys which acted as mine spotters and carried Explosive Ordinance Disposal divers. AH-1J Cobras provided air fire support since the Sea Dragons have no armament (other than small .50 caliber machine guns) and have limited manueverability under tow. Following Desert Storm, both AMCM squadrons (HM-14 and HM-15) went from 12 to 8 MH-53E aircraft, and the Naval Reserve squadrons upgraded from the RH-53D to the MH-53E. In 1992 the Commander, Mine Warfare Command assumed operational command of the AMCM squadrons. In 1994 and 1995, the Reserve AMCM squadrons were disestablished while Naval Reserve personnel and aircraft merged with the active duty squadrons to form two 12 aircraft integrated squadrons. In 1997, the USS INCHON (MCS-12)became operational as the Mine Countermeasures Command and Support ship. The HM squadrons received a dedicated platform from which they could launch AMCM missions from the sea.
Only two other countries are known to have an aerial minesweeping capability. The Russians have used the Mi-14 Haze with mechanical minesweeping gear. While Japan has a squadron of 12 Sikorsky S-80M-1's, a variant of the MH-53E, with a variety of AMCM systems similar to those employed by the United States. The U.S. Navy Airborne Mine Countermeasures Community has many question marks in its future. While the MH-53E is slated to receive upgrades to it's engines, they are slow in coming, and a long awaited Navigation/Communication System upgrade to the cockpit has been cancelled. Improvements to many AMCM systems are also planned, including an improved MK-105 hydrofoil sled, a new sonar system (AQS-20), and a new shallow water influence magnetic sweep system (SWIMS) which can be transported internally. Though currently only a day VFR operation, night missions are envisioned in the future, however the cockpit of the MH-53E must be altered as it it not currently night vision goggle (NVG) compatible. History has proven time and again that mines will continue to be a dominant factor in control of the seas. Inevitably, airborne mine countermeasures will continue to play a role in finding and eliminating this ever present threat. |
|
Home Page | AMCM | AMCM History | Naval Mines | Mine History | Glossary | E-mail addresses | FAQ | Links MH-53E | HM-12 | HM-14 | HM-15 | HM-16 | HM-18 | HM-19 | HSL-94 | AWSTS | CSS | USS INCHON
This site is designed and maintained by LT Mark Zwolski DISCLAIMER |
 |
when this page is updated. |
