A new helicopter specifically designed for external vertical lift operations, such as moving transportable rig components or seismic equipment in remote locations, operates more efficiently than most other medium or heavy lift helicopters, according to manufacturer Kaman Aerospace.
The single pilot helicopter was designed as an "aerial truck" for efficient lifting of heavy loads but with the operating costs of a light lift craft.
The K Max helicopter can lift more pounds of cargo per gallon of fuel consumed than other similar helicopters, according to Kaman. For example, to transport a 5,000 lb load at an elevation of 8,000 ft, the K Max helicopter consumes 85 gal of fuel/hr. Under the same load conditions, the next most efficient commercially available helicopter consumes 160 gal of fuel/hr and requires two pilots.
The 4,500 lb helicopter can lift 5,000 lb to an altitude of 8,000 ft or about 6,000 lb at low altitudes.
The first production aircraft flew in September 1993, and the first commercially available aircraft was built in January.
The initial price of the helicopter is $3.5 million. Through 1995, 14 aircraft are planned to be built, according to Kaman.
DESIGN
The K Max helicopter is designed with two counter-rotating intermeshing rotors and no tail rotor (Fig. 1). Thus, all the engine power is available to the main rotors for lift, improving vertical-lift efficiency.
The intermeshing rotors provide the counter torque normally provided by a tail rotor, which can require up to 30% of the engine's power during heavy load operation. Without a tail rotor, all available power is used for lift.
The tail rotor drive train, maintenance, noise, vibration, and safety hazard are eliminated.
One drawback of the intermeshing rotor configuration is a low forward speed, about 100 115 knots.
However, most external-lift operations involve hovering and short hops at low speeds.
To change direction, an aerodynamic servo flap rotor control system adjusts the pitch of the main blades by living the blades to the required angle of attack. Only the flap moves, not the entire blade as on conventional helicopters. This light mechanical system replaces the heavier mechanical and hydraulic systems on conventional helicopters.
COST EFFICIENCY
In many situations, exploration companies that contract helicopters in remote areas are responsible for all logistical support costs. The cost of fuel and its transportation to a site can be quite expensive. The cost of helicopter fuels runs about $1/gal, but the cost to transport it in drums to a remote site may be triple that amount. A helicopter's efficiency is measured in the weight transported per gallon of fuel consumed. Thus, greater fuel efficiency (more load per gallon of fuel) can reduce logistics costs.
The K Max's operational costs are reduced primarily, because the helicopter requires only one pilot, uses less fuel to haul a standard load, and has less down time because simple mechanical systems are used, according to Kaman.
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