All Weather Ops



    The most important effect of high ambient temperature and/or low barometric pressure on drone operations is the relatively large reduction in shaft horsepower available from the gas turbine engine. A secondary effect of increased temperature and/or decreased pressure (reduced density) is a small de- crease in aerodynamic efficiency of the rotor system. (It should be noted that humidity, by itself, does not have any noticeable influence on gas turbine engine shaft horsepower output or aerodynamic efficiency of the rotor system.) Any variation in drone performance in forward flight in extreme hot weather is considerably less than 5 percent, and the resulting mission time or endurance is only similarly affected.

    The only performance parameters that are influenced to any appreciable degree by hot weather are those involving the use of maximum engine shaft horsepower available, i.e. vertical and maximum (forward flight) rate of climb. Since maximum (forward flight) rate of climb capability will always be of substantial magnitude so long as even a small amount of excess horsepower is available in a hover, extreme variations in ambient conditions cannot cause this performance parameter to approach marginality. Thus the only flight parameter, which can be sufficiently influenced by hot weather, such that marginal or inadequate performance might result, is rate of climb at zero translational velocity with respect to the air mass (vertical rate of climb).

    Refer to the "Normal Procedures" section for low pressure and high temperature operating techniques and to the "Performance Data" section for vertical rate of climb data.



No special procedures are required for operation of the drone in cold weather.

    The drone is not provided with an operable anti- icing system at this time. Heater mats are installed in the leading edge of the fiberglass rotor blades for future use.



The drone is equipped with lights for night operation.



Operations in light rain only are permissible, until the drone is equipped with all weather features.


End of All Weather Operations Section

Home Up Description Normal Procedures Emergency Procedures Auxiliary Equipment Operating Limitations Flight Characteristics Systems Operation Crew Duties All Weather Ops Performance Data


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