MAXIMUM PERFORMANCE TAKEOFF
A maximum performance takeoff is used to climb at a steep angle to clear barriers in the flight path. It can be used when taking off from small areas surrounded by high obstacles. Before attempting a maximum performance takeoff, you must know thoroughly the capabilities and limitations of your equipment. You must also consider the wind velocity, temperature, altitude, gross weight, center-of-gravity location, and other factors affecting your technique and the performance of the helicopter.
To safely accomplish this type of takeoff, there must be enough power to hover, in order to prevent the helicopter from sinking back to the surface after becoming airborne. This hover power check can be used to determine if there is sufficient power available to accomplish this maneuver.
The angle of climb for a maximum performance takeoff depends on existing conditions. The more critical the conditions, such as high density altitudes, calm winds, and high gross weights, the shallower the angle of climb. In light or no wind conditions, it might be necessary to operate in the crosshatched or shaded areas of the height/velocity diagram during the beginning of this maneuver. Therefore, be aware of the calculated risk when operating in these areas. An engine failure at a low altitude and airspeed could place the helicopter in a dangerous position, requiring a high degree of skill in making a safe autorotative landing.