Anytime you are planning to land or takeoff at an unfamiliar site, you should gather as much information as you can about the area. Reconnaissance techniques are ways of gathering this information.
The purpose of a High Reconnaissance is to:
Determine the suitability of the landing area.
Determine the wind direction and speed.
Obstacles and their effect on wind patterns.
Select the approach and departure axes.
Select a point for touchdown.
Plan the most suitable flight paths into and out of the area.
Altitude, airspeed, and flight pattern for a high reconnaissance are governed by wind and terrain features. You must strike a balance between a reconnaissance conducted too high and one too low. It should not be flown so low that you have to divide your attention between studying the area and avoiding obstructions to flight. A high reconnaissance should be flown at an altitude of 300 to 500 feet above the surface. A general rule to follow is to ensure that sufficient altitude is available at all times to land into the wind in case of engine failure. In addition, a 45 degree angle of observation generally allows best estimation of the height of barriers, the presence of obstacles, the size of the area, and the slope of the terrain. Always maintain safe altitudes and airspeeds, and keep a forced landing area within reach whenever possible.
A Low Reconnaissance is accomplished during the approach to the landing area (Except when a running landing is necessary). When flying the approach, verify what was observed in the high reconnaissance, and check for anything new that may have been missed at a higher altitude, such as wires, slopes, and small crevices. If everything is alright, you can complete the approach to alanding. However, you must make the decision to land or go-around before effective translational lift (ETL) is lost.
If a decision is made to complete the approach, terminate it in a hover, so you can carefully check the landing point before lowering the helicopter to the surface. Under certain conditions, it may be desirable to continue the approach to the surface. Once th helicopter is on the ground, maintain operating RPM until you have checked the stability of the helicopter to be sure it is in a secure and safe position.
Prior to departing an unfamiliar location, make a detailed analysis of the area. There are several factors to consider during this evaluation. Besides determining the best departure path, you must select a route that will get your helicopter from it's present position to the takeoff point.
Some things to consider while formulating a takeoff plan are the aircraft load, height of obstacles, the shape of the area, and direction of the wind. If the helicopter is heavily loaded, you must determine if there is sufficient power to clear the obstacles. Sometimes it is better to pick a path over shorter obstacles that to takeoff directly into the wind. You should also evaluate the shape of the area so that you can pick a path that will give you the most room to maneuver and abort the takeoff if necessary. Wind analysis also helps determine the route of takeoff. The prevailing wind can be altered by obstructions on the departure path, and can significantly affect aircraft performance. One way to determine the wind direction is to drop some dust or grass, and observe which way it is blowing. Keep in mind that if the main rotor is turning, you would need to be a sufficient distance from the helicopter in order to not have a false indication.
If possible, you should walk the route from the helicopter to the takeoff position. Evaluate obstacles that could be hazardous and ensure that you will have adequate rotor clearance. Once at the downwind end of the available area, mark a position for takeoff so that the tail and main rotors have sufficient clearance from any obstructions behind the helicopter. Use a sturdy marker, such as a heavy stone or log, so it does not blow away.
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Page Last Updated on: Nov-06-2017
