The Army's 12th Aviation Battalion operates UH-1 "Hueys" and VH-60 helicopters to provide priority air transport of Congress, the senior leadership of the Department of Department of Defense and other federal and state agencies in the National Capital Region. The 5 assigned VH-60 Blackhawks are specially modified, and are the only aircraft of this type in the US Army.
The Marine Corps VH-60N is a helicopter transport for the President of the United States, Vice President, and other visiting heads of state. It has seating provisions for 10 passengers and the aircrew consists of a pilot, co-pilot, crewchief, and a communication system operator. As an executive transport, it has an interior suitable for executive travel and receives extensive care and maintenance exceeding normal standards to keep the aircraft in superior condition. The VH-60N can be folded quickly, in less than two hours, for loading and storage onto an Air Force C-5A/B, and C-17, allowing for transport on short notice. It is also capable of being loaded onto an Air Force B, C-130, and C-141. Marine Helicopter Squadron One [HMX-1] is the sole helicopter support for executive transport throughout the United States and overseas.
VH-60N is in Phase III, Production, Deployment, and Operational Support phase of its life cycle. The VH-60N is expected to remain in service until the year 2015, after which a determination will be made whether it should undergo a Service Life Extension Program, which could potentially extend it's life to the year 2025. Naval Air System Command contracts for instruction of pilots, communication system operators, and maintenance personnel at the squadron in HMX-1 Quantico, Virginia for the VH-60N. No specific military aircrew or maintenance training exists for the VH-60N. On 26 November, 1995, the Secretary of Defense directed the Department of the Navy to procure a VH helicopter pilot simulator for HMX-1. A contract to procure the VH-60N Aircrew Proficiency Trainer was awarded in April 2000.
The VH-60N is single main rotor, twin engine helicopter, designed as an executive transport. The VH-60N aircraft systems, furnishings and equipment have been optimized for executive transport missions. The main and tail rotor blades, stabilator, and tail rotor pylon can fold to reduce dimensions for air transportability or storage.
The aircrew consists of a pilot, co-pilot, communications system operator, and crewchief. When on a mission, the detachment is completely self-contained, supported by dedicated aircrew, maintenance, technical representatives, security personnel and logistics. In addition to its Executive air support role, it also provides support for emergency evacuation, development of new systems, and training of new helicopter tactics.
The VH-60N is still in production at the Sikorsky Aircraft Division of United Technologies. The VH-60N has an original service life expectancy of 7,500 flight hours (the "fleet" standard service life) based on its original design and evaluative process. The aircraft are constantly monitored for appropriate maintenance schedules, and modifications to established maintenance procedures are instituted each time an indication of necessity or desirability for such change occurs. . Since the VH-60N airframe is a newer technology, for which many components have not even been assigned a service life expectancy, detailed study has gone into arriving at service life designations to be applied based on safety/reliability assessments on their design. Once those limits have been established, they are rated out and replaced at approximately 75% of their life expectancy.
On 19 May 1993 a VH-60N helicopter crashed while flying a local maintenance evaluation flight near Washington, D.C. While conducting an autorotation to verify the rotor RPM (NR) setting during autorotations (autoturns) and evaluate a previous transient power turbine speed (NP) discrepancy, the aircrew experienced a dual engine flame-out resulting in a full autorotation into a wooded site. Engineering investigation analysis indicated that the load demand spindle (LDS) roll pins were improperly installed. The LDS system is a load anticipator that is designed to reduce transient NP/NR droop during collective flight control demands. The improperly installed LDS roll pins, coupled with a suspected high autoturn setting allowed the engines to reach an overspeed condition that activated the engine overspeed protection system causing both engines to flame-out. The mishap aircraft did not have an "auto restart" capability at the time of the mishap (although it is by no means clear that such a capability could have resulted in sufficient engine torque to have altered the situation measurably). The cause of the mishap was failure to comply with proper installation and quality assurance procedures by squadron maintenance personnel.
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