Figure 30-2: Straight and Level Flight
As noted above, Figure 30-2 depicts a selective radial scan pattern for straight and level flight. The answer to the question, What information do I need to fly straight and level?, is information on heading and altitude. The answer to the next question, Which instruments give me the needed information?, is the heading indicator and the altimeter. To answer the question, Is the information reliable? ,the pilot must:
1. confirm the reliability of the heading indicator by referring to the compass and the turn and bank; and
2. confirm the reliability of the altimeter by referring to the vertical speed indicator and airspeed indicator.
In all four diagrams, the heavy arrows depict the scanning pattern the pilot uses most frequently to acquire the needed information. The light arrows indicate a less frequently repeated scan of the supporting instruments. This scan is used to confirm that the main instrument indications are reliable, and also to determine if there is any trend toward an undesired flight condition. The supporting instruments that are more relevant to the task at hand are viewed more frequently than the others. For example, when the pilot is more concerned about altitude control, the VSI would logically be more frequently viewed than the turn and bank indicator.
Figure 30-3: Straight Climb
Figure 30-3 shows the correct scanning pattern for the straight climb. The heavy arrows show that the pilot pays most attention to heading and airspeed while climbing. The light arrows depict the important (but less frequent) scan used to confirm heading and attitude information. For the straight climb, the pilot uses the turn and bank and magnetic compass to confirm the heading. The information from the VSI and altimeter confirms that the aircraft is performing as expected in the climb.
By interpreting the information on climb performance and power, the pilot can determine if the attitude indicator is reliable.
Figure 30-4: Approaching Desired Altitude
Figure 30-4 shows the most appropriate scan as the helicopter nears the assigned altitude. At this point, airspeed information becomes less important than the altitude information. During the transition from the climb to straight and level flight, the pilot uses the scan pattern that gives more frequent attention to the attitude indicator, with support from the heading indicator and altimeter.
Figure 30-5: Level, Approaching Desired airspeed
As the cruise attitude is established, the pilot should allow the helicopter to accelerate to cruise speed before setting the cruise power. As shown in Figure 30-5, as the helicopter approaches the cruising attitude, airspeed information becomes more important, and the ASI is again scanned more often, along with the attitude indicator. The pilot also scans the heading indicator and altimeter often to establish and maintain cruise flight.
INSTRUMENT EXERCISES
STRAIGHT AND LEVEL FLIGHT
This consists of flying at a constant altitude (power setting), airspeed and heading (adjusted with cyclic). The rotor disc (miniature aircraft wings) should be level with the horizon on the attitude indicator if the instrument has been adjusted correctly.
When an instrument indicates an adjustment is required to maintain desired performance, the pilot will determine the necessary amount from other instruments. Airspeed, torque/MP, and/or altimeter indicate the adjustment to be made in power or attitude. Corrections to changes in attitude should be made as soon as noticed. Then instead of fixating on that particular instrument to note the effect, the scan is continued to finally return to the original instrument. In this way the entire panel reflects the effect of the adjustment.
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本文链接地址：直升机飞行训练手册 HELICOPTER FLIGHT TRAINING MANUAL(60)
