Military


MH-53E Sea Dragon

On 19 July 2012, an MH-53E Sea Dragon helicopter assigned to the US Navy's Helicopter Mine Countermeasure Squadron 15 crashed 58 miles southwest of Muscat, Oman while conducting heavy lift support operations. HM 15 had been conducting operations in the region, including in cooperation with the USS Ponce, and may have had a detachment assigned to the ship. The Department of Defense immediately noted that the crash was not due to hostile activity, though the status of the aircraft's 5 crewmembers was not initially clear. Another MH-53E helicopter assigned to the same squadron was sent to the scene, where it provided search and rescue assistance.

The newest military version of Sikorsky's H-53E/S80 series, the MH-53E Sea Dragon, is the Western world's largest helicopter. The MH-53E is used primarily for Airborne Mine Countermeasures (AMCM), with a secondary mission of shipboard delivery. Airborne Mine Countermeasures (AMCM) missions include mine sweeping and ancillary spotting, mine neutralization, floating mine destruction, channel marking, and surface towing of small craft and ships. Additional mission capabilities include air-to-air refueling, hover in-flight refueling, search and rescue, and external cargo transport operations, in both land and seaborne environments. The MH-53E Helicopter also has the ability to perform Vertical Onboard Delivery (VOD) missions as well as transportation of personnel and cargo.

Developed by Sikorsky, the MH-53E is a reconfigured version of the CH-53E Super Stallion presently being used by the Marine Corps. Both the CH-53E and MH-53E are involved in development and modernization programs. They will continue to provide a myriad of support functions for the fleet in the area of heavy and medium lift requirements. The prototype, MH-53E, made its first flight on 23 December 1981. It underwent evaluation and testing at the Naval Coastal Systems Center in Panama City, Fla. The MH-53E was derived from the CH-53E Super Stallion and is heavier and has a greater fuel capacity than its ancestor. The MH-53s can operate from carriers and other warships. Sea Dragon is capable of carrying up to 55 troops or a 16-ton payload 50 nautical miles or a 10-ton payload 500 nautical miles. The MH-53E is capable of towing a variety of mine-sweeping countermeasures systems, including the Mk 105 minesweeping sleed, the ASQ-14 side-scan sonar, and the Mk 103 mechanical minesweeping system.

The MH-53E's triple turbine engines provide greater lift for mine countermeasures operations while enlarged sponsons carry additional fuel to allow up to six hours of time on station. The new configuration also features the airborne mine countermeasures coupled, dual digital automatic flight control system. The system consists of two digital computers, a cockpit control box, six accelerometers, and five position sensors. It is 42 percent lighter, occupies 54 percent less volume and consumes 41 percent less power than the older analog system. There is no organizational level maintenance required. The computers continually cross-check one another and disable any potential false inputs to the automatic flight control system servos. If one computer fails, the other will automatically double its output, eliminating any degradation in automatic flight control performance.

Also part of the new mine countermeasures capability is a dedicated AMCM hydraulic system, improved AMCM navigation, 30,000-pound tension tow boom, better mirrors and better crew environment. The MH-53E Super Stallion is capable of inflight refueling and can be refueled at hover. It is also shipboard compatible with amphibious ships serving as airborne mine countermeasures platforms. The aircraft will sweep waterways for mines by flying above the surface, towing electronic or magnetic sweeping gear as well as gear for neutralizing moored mines.

A new type of Navy squadron was developed by combining active duty squadrons with Naval Reserve squadrons resulting in two integrated Helicopter Mine Countermeasures Squadrons (HM), each comprised of six active duty and four reserve MH-53E Aircraft -- HM-14, Naval Base (NB) Norfolk, Virginia; and HM-15, Naval Air Station (NAS) Corpus Christi, Texas. These integrated squadrons each contain ten aircraft; six active duty and four reserve. The primary mission of HM-14 and HM-15 is minesweeping that is conducted independently or in conjunction with surface forces. Mine sweeping missions either use all squadron aircraft assets or deploy separate detachments, as stated in the Required Operational Capability and Projected Operational Environment (ROC/POE).

The MH-53E Helicopter is a new production aircraft first introduced to the fleet in Fiscal Year (FY) 87. New production aircraft were delivered to the Naval Air Reserve beginning in November 1993. Forty-four MH-53E helicopters have been delivered to the Navy. The MH-53E Helicopter replaced the RH-53D in the fleet and fleet reserve squadrons. MH-53E deliveries to HM-14 and HM-15 (including Reserves) are completed.

Helicopter Combat Support Squadron (HC)-4 in Sigonella, Sicily, transitioned from CH-53E to MH-53E Helicopters on a one-for-one basis, for a total of nine aircraft. This transition took place between April and September 1995. The mission of HC-4 was not affected by this transition; their assigned MH-53Es are not configured for AMCM missions, and are used primarily in fleet support roles.

The MH-53E Helicopter was procured by Japan directly from Sikorsky Aircraft Corporation. The Navy provides support for the procured aircraft through the H-53 Foreign Military Sales (FMS), Program Manager, Air (PMA) 226-0121, Cherry Point.

All MH-53E Helicopter Pilots receive ground training and aircraft familiarization using simulators at Airborne Mine Countermeasures Weapon Systems Training School (AWSTS), Norfolk, Virginia. Basic MH-53E Pilot and Aircrew flight training is conducted at HMT-302, Marine Corps Air Station New River, North Carolina. Flight crews destined for AMCM activities receive further mission and tactics training at AWSTS, while MH-53E fleet support Pilots and Aircrew proceed directly to HC-4, Sigonella, Sicily. Organizational level maintenance training is conducted at Maintenance Training Unit (MTU) 1031, Naval Air Maintenance Training Unit, Norfolk, Virginia.

For AMCM missions, the MH-53E Helicopter is operated by a crew of seven consisting of pilot, copilot, safety observer, port and starboard AMCM equipment handlers, and port and starboard ramp operators. Enlisted personnel from aviation maintenance ratings with Navy Enlisted Classifications (NECs) 8225 or 8226 perform aircrew duties. These squadrons also perform secondary missions such as transportation of passengers, equipment, and cargo, as well as VOD missions.

The T64-GE-419 engine, AN/ARC-210(V), R-2606/U GPS, and AN/ARC-220 are being retrofitted into the MH-53E by field modification teams or by the Naval Aviation Depot (NAVAVNDEPOT) Cherry Point, North Carolina, during scheduled Standard Depot Level Maintenance (SDLM). The minor changes to the MH-53E Helicopter will also be introduced into the fleet by field modification teams or during SDLM. The main gearbox ECP will be retrofitted on an attrition basis.

The MH-53E Helicopter is a CH-53E modified to perform AMCM missions. The modifications include:

  • Enlarged sponsons
  • Rear escape hatches
  • Improved tail rotor system
  • Airframe structural reinforcement
  • 30,000-pound tension tow boom
  • 90-degree stub ramp
  • Winch control system
  • AN/APN-217(V)2 Doppler Radar
  • A second AN/APN-171(V) Radar Altimeter
  • Improved mirrors
  • Equipment stowage box
  • Mk-104 davit hardpoints
  • Egress lighting
  • Guillotine, tension, and skew system
  • Tow hook release system
  • Transfer hook and control system
  • Smoke marker rack
  • XM-218.50 caliber machine gun

The MH-53E Helicopter retained approximately 80 percent of the CH-53E configuration. The physical changes include the larger fuel sponsons and auxiliary AMCM equipment. The newly designed sponsons each contain two fuel tanks. This allows for a total fuel capacity of 3,200 gallons, which will increase both aircraft range and loiter time. Two enlarged window-type escape hatches in the aft cabin area permit easier egress for aircrew in an emergency situation. An A-frame suspension system is stowed in the forward position.

The Tow Boom is a fixed length four-inch diameter composite tubing that increases towing capacity. The boom has 32 degrees of movement in the pitch plane, and can yaw about the vertical axis to either side of the cabin. The forward end of the boom is set in sleeve bearings to allow operating motion for a load cell that monitors tow loads.

The power for the MH-53E Helicopter is currently furnished by three T64-GE-416 or -416A Engines. Upgraded engines are installed on 14 MH-53E Helicopters out of 44 aircraft in the fleet. This new engine, the T64-GE-419, increases engine performance and allows for contingency power during a One-Engine-Inoperative condition. The Main Gearbox improvement program will provide greater reliability and an increased time between unscheduled removals. This redesign effort for fleet aircraft will be accomplished through an ECP. The MH-53E Helicopter has a modified CH-53E Hydraulic System consisting of an additional 3,000 pounds per square inch hydraulic supply system dedicated to AMCM.

In addition to the onboard fuel system, the MH-53E Helicopter has air-to-air and Helicopter-In-Flight Refueling (ship-to-air) pressure refueling systems, an inner tank fuel dump system, and a range extension fuel transfer system. The MH-53E Helicopter has enlarged fuel sponsons and uses a new fuel management system. There are three independent suction-pressure type fuel systems, one for each engine. The fuel systems are joined by a crossfeed system for maximum fuel utilization.

The flight station design for the MH-53E Helicopter differs from the CH-53E in the gages, switches, and circuit breaker panels necessary for effective AMCM aircraft operations. Some modifications to the flight station layout will result from the Navigation and Communication System integration. Due to the additional electronic equipment, the MH-53E Helicopter wiring system and circuit breaker panel have been redesigned.

The Digital Automatic Flight Control System Coupler System has been incorporated with modifications to the MH-53E Helicopter Digital Automatic Flight Control System (AFCS) computer. This provides longitudinal and lateral ground speed control, selected ground speed stabilization, and automatic altitude retention.

The AN/ARN-151 GPS is being replaced by the R-2606/U MAGR 2000 GPS, fully integrated with the aircraft navigation instruments and providing non-precision approach capability. The AN/APN-217(V)2 Radar Navigation Set is a Doppler radar that measures aircraft ground speed and drift angle. It has the unique ability to perform accurately at low airspeeds over smooth water. Additional navigation systems aboard the MH-53E Helicopter include two AN/APN-171(V) Radar Altimeters, the AN/ARN-118(V) Tactical Air Navigation (TACAN), AN/ARN-89A Automatic Direction Finder, VIR-31A Very High Frequency Omni Directional Radio (VOR)/Instrument Landing System (ILS) navigation system, and vertical gyro system.

The two AN/ARC-182(V) Radios provide direct securable communications in the Ultra High Frequency (UHF) and Very High Frequency (VHF) bands. When operated with a C-11984 Control Unit, the AN/ARC-182(V) provides a frequency hopping anti-jam capability in the UHF mode. Other communication systems aboard the MH-53E Helicopter include the AN/ARC-174A(V)2 High Frequency Radio, AN/APX-72 Identification Friend or Foe Transponder, KIT-1A/TSEC Computer Transponder, TSEC/KY-58 Secure Voice Data Set, and the AN/AIC-14A Intercom. The AN/ARC-182(V) Radio is being replaced by the AN/ARC-210(V) ECCM Radio System, and the AN/ARC-174 is being replaced by the AN/ARC-220 to provide a data-link capability. The AN/ARC-210(V) provides normal and secure communication in the Amplitude Modulation and Frequency Modulation modes in both UHF and VHF bands. It is compatible with the TSEC/KY-58, has frequency hopping jam-resistant capabilities, and is interoperable with other Air Force and Army radio systems.

The Airborne Mine Countermeasures Navigation includes the PNS, a navigation system that has been integrated with the AN/ARN-151 Receiver (which was part of the AN/ARN-151 provisions installation). It is used for precise mine field navigation during AMCM missions. The interim GPS functions are assumed by the R-2606/U GPS when integrated into the MH-53E Helicopter.

The AN/ALE-39 Countermeasures Dispensing System is mounted either internally or externally and is designed to dispense chaff, infrared decoy flares, or expendable jammers.

Several modifications to the MH-53E Helicopter are planned over the next few years. These modifications include upgrading to the T64-GE-419 engine, upgrading to the MAGR 2000 Global Positioning System (GPS), an Engineering Change Proposal to the main gearbox, and other minor Airframe Change modifications to the helicopter.

An MH-53E Sea Dragon helicopter of the Helicopter Mine Countermeasures Squadron (HM) 14 Vanguards went down during a routine training mission in the Atlantic Ocean 25 January 2005 approximately 28 miles off the coast of Virginia at approximately 3 p.m. with eight people aboard. All eight were rescued and are being transported by two MH-60S Knighthawk helicopters to Portsmouth Naval Medical Center.

Airborne Mine Countermeasures Equipment

The MH-53E Helicopter is capable of using a variety of AMCM equipment described below. In addition, new AMCM equipment is currently in various stages of development. These include the AN/AQS-20 Sonar Detecting Set, Airborne Laser Mine Detection System (ALMDS), A/N37U-1 Mine Clearing Set for moored mines, and Airborne Mine Neutralization System (AMNSYS).

The AN/SPU-1/W is a single magnetized orange pipe mine sweeping system which may be externally transported to and from the operating area by an appropriately configured MH-53E Helicopter. The MH-53E Helicopter is capable of towing a single unit or three units in tandem; however, streaming and recovering tandem units is accomplished from surface craft or shore ramp facilities.

The Mk-103 Mod 2 is a mechanical mine sweeping system used for sweeping moored mines. This system is streamed, towed, and recovered by an appropriately configured MH-53E Helicopter. The system is a port and starboard diverted wire sweep that is armed with cutters. The sweep wires are diverted by otters and supported by marker floats.

The Mk-104 Mod 3 acoustic mine sweeping gear generates a sound field capable of actuating acoustic mines. The acoustic gear is designed to be streamed, towed, and recovered by appropriately configured MH-53E Helicopters.

The Mk-105 is a magnetic influence sweep device. The MH-53E Helicopter is not capable of carrying this device; therefore, it is streamed from a surface vessel or shore site. The helicopter acquires the tow cable and aircrews make the electrical and mechanical connections necessary to begin towing operations. When the mission is completed, the tow cable is transferred to another helicopter or back to personnel either aboard a surface vessel or ashore.

The Mk-106 is a combination of acoustic and magnetic sweep formed by attaching the Mk-104 to the Mk-105. General operating procedures are identical to the Mk-105 procedures.

The AN/AQS-14 Sonar Detecting Set is a high resolution, dual side-looking, mine-hunting sonar that is used for detection, classification, and marking of mines and other underwater objects. The sonar's transducers are housed in an underwater towed vehicle while the information processing and display equipment and controls are located in the helicopter. The sonar components are divided into three major groups; underwater towed vehicle, electro-mechanical tow cable, and airborne electronic assembly. The AN/AQS-14 is streamed, towed, and recovered by the MH-53E Helicopter.

The AN/ALQ-141 Acoustic Mine Countermeasures equipment is capable of actuating acoustic mines. The AN/ALQ-141 is composed of the towed sonar vehicle, the electro-mechanical tow cable, and the MH-53E mounted electronic controls. The AN/ALQ-141 is capable of being streamed, towed, and recovered by an appropriately configured MH-53E Helicopter.

The AN/AQS-20 Sonar Detecting Set is a high-resolution sonar that provides the fleet with the operational capability to hunt mines from air and surface craft. The AN/AQS-20 system was initiated to develop a high-speed reconnaissance and mine hunting sonar capable of searching large volumes of the sea for mine-like objects with a high probability of detection and classification and low probability of false alarms. This information is used for mine avoidance and neutralization.

The Airborne Laser Mine Detection System [ALMDS] is an airborne electro-optical system that is capable of rapid detection, classification, and localization of floating and moored mines located in relatively shallow water. With input from GPS, accurate navigation data is provided to determine target location. Operation of the ALMDS consists of firing a pulsed laser into the water and imaging any objects within the illuminated sector using a gated camera system.

The A/N37U-1 Mine Clearing Set, Moored Mines system consists of sweepwires which deploy Mk-17 Mod 1 cutters to sever mine moorings; electro-mechanical depressors which "fly" submerged in the water to maintain predetermined sweep depth; electro-mechanical otters, which function like depressors, but also separate the port and starboard sweepwire sections in order to maintain the proper sweep width; and one or more sections of Kevlar tow wire, depending on the desired sweep depth.




NEWSLETTER
Join the GlobalSecurity.org mailing list