直升机教员手册 Helicopter Instructor’s Handbook
时间：2014-11-10 08:35来源：FAA 作者：直升机翻译 点击：次
|
To view this page ensure that Adobe Flash Player version 9.0.124 or greater is installed. Alert the student to the problem of losing the wind when the helicopter descends below the height of the obstacle, normally on the final stages of the approach. Have the student plan and think ahead of the aircraft. Discuss the consequences of less wind upon descending into the confined area. Does the student comprehend that losing favorable wind velocity may have the same effect as losing ETL? Help the student anticipate the potential increased rate of descent and corresponding need for power. Takeoff A confined area takeoff is considered an “altitude over airspeed” maneuver. This means it is more important to gain altitude than airspeed. Make the best takeoff possible to attain a normal attitude and climb airspeed to avoid or exit the crosshatched or shaded areas of the height/velocity diagram as quickly as possible. Because this is primarily an altitude acquiring maneuver, it usually requires lowering the nose to gain airspeed after the obstructions are cleared. Before takeoff, make a ground reconnaissance to determine the type of takeoff to be performed. Doing so helps determine the point in which the takeoff should be initiated to ensure the maximum amount of available area, and how to best maneuver the helicopter from the landing point to the proposed takeoff position. If wind conditions and available area permit, the helicopter should be brought to a hover, turned around, and hovered forward from the landing position to the takeoff position. Under certain conditions, sideward flight to the takeoff position may be necessary. If rearward flight is required to reach the takeoff position, the pilot must attempt to see what is behind the helicopter prior to hovering backwards. Hovering backward in a confined area is not recommended unless the pilot is absolutely sure that the area is clear of trees, high sloping terrain, or any other obstacle that the tail rotor could strike. If there is no other option and there are two pilots available, it would be beneficial to get out of the helicopter and visually inspect the area first. When planning a takeoff, consider power available, wind direction, obstructions, and forced landing areas. The angle of climb on takeoff should be normal, or at least no steeper than necessary to clear any barrier. It is better to clear a barrier by a few feet while maintaining normal operating rpm with perhaps a reserve of power, than to clear a barrier by a wide margin but with a dangerously low rpm and no power reserve. As an aid in helping to fly up and over an obstacle, have the student form an imaginary line from a point on the leading edge of the helicopter to the highest obstacle to be cleared. Fly this line of ascent with enough power to clear the obstacle. As a rule of thumb, during the climbout, if there is an observed distance between the rotor tip-path plane and the obstacle, the obstacle will most likely be cleared. After clearing the obstacle, maintain the power setting and accelerate to the normal climb speed. Then, reduce power to the normal climb power setting. The instructor should also explain that the leading edge of the landing gear needs to clear the obstructions as well. Often, the student begins to get in a hurry and nose the helicopter over to speed up the process, but this lack of patience could cause the landing gear to contact leaves and limbs. The student must observe where both points are relative to the obstruction(s) during takeoff. In the event that it appears the helicopter will not clear the obstacle (i.e., the tip-path plane is below the obstacle), take the appropriate action to abort the takeoff. This decision should be made earlier in the approach rather than waiting until the student finds the helicopter at maximum power and with fewer options available. Demonstrate that aircraft control can be maintained by flying the aircraft back down the flightpath if necessary. If the student is going to pursue flight at higher elevations and small areas, training in the vertical takeoff method with aborts back into the confined area would be advisable to demonstrate the different performance of the helicopter. Proper heading control is very important to maintain tail rotor clearances. Aborted confined area takeoffs should terminate close to the forward barriers to ensure tail rotor clearance. All instructors should have designated confined areas established to conduct various proficiency based levels of training. A new student will probably need a large open area. As coordination and proficiency levels increase, the student should be introduced to smaller, more challenging confined areas. Those same smaller confined areas are suitable for training of more advanced students, such as a commercial pilot applicants. Several areas should be used to give the student every opportunity to consider all of the factors that influence operation into and out of confined areas. Have the student fly over a projected landing area and then describe the factors involved in a landing to that specific area. Items such as wind direction, favorable approach path, suitable forced landing areas, obstacles to be cleared, where turbulence might be encountered, and the helicopters expected performance should be discussed relative to each approach. The student must also consider the performance capability of the helicopter when planning a departure from a confined area. As an instructor, maintain awareness of the disadvantages of seasonal training. A student that learns these maneuvers in the fall or winter months will not be prepared for the environmental consequences of warmer weather. Discuss this with the student, increasing general awareness of the potential impact of different seasonal conditions. A good discussion on performance would include having the student compare the charted and experienced performance values against those from a typical hot summer day. If the charts furnish sufficient information, the instructor might be able to adjust the power to simulate that of a hot summer day and how the helicopter performance is different. |
推荐内容
热点内容
