by Jonathan M. Stern
Combinations of the Four Fundamentals
You now have learned how to use your instruments to perform the four fundamentals. All that remains of basic attitude instrument flying are the two hybrids, climbing and descending turns. These flying maneuvers are simply combinations of the four fundamentals, which you have already learned. If they are more difficult, the difficulty arises only from the fact that more things are going on at the same time. In a climbing turn, not only is the heading changing, but the altitude also is increasing. It becomes all the more important to continue to scan the instruments. If you fixate on one instrument, say the altimeter, it is likely that you will neglect to roll out on your desired heading. (See Figure 12.5.)
Figure 12.5. Fixation on one instrument (in this case, the heading indicator) leads to control errors. Here, the airspeed and descent rate are excessive.
Table 12.5 shows the primary pitch, bank, and power instruments used for the different types of climbing and descending turns.
|TABLE 12.5 Instruments for Climbing And Descending Turns|
|Constant Rate Climb With Standard Rate Turn||VSI||Turn Coordinator||Airspeed|
|Constant Rate Climb With Constant Bank Turn||VSI||Attitude||Airspeed|
|Constant Rate Descent With Standard Rate Turn||VSI||Turn Coordinator||Airspeed|
|Constant Rate Descent With Constant Bank Turn||VSI||Attitude||Airspeed|
|Constant Airspeed Climb With Standard Rate Turn||Airspeed||Turn Coordinator||Manifold pressure or Tachometer|
|Constant Airspeed Climb With Constant Bank Turn||Airspeed||Attitude||Manifold Pressure or Tachometer|
|Constant Airspeed Descent With Standard Rate Turn||Airspeed||Turn Coordinator||Manifold Pressure or Tachometer|
|Constant Airspeed Descent With Constant Bank Turn||Airspeed||Attitude||Manifold Pressure or Tachometer|
Now you can try a constant rate climbing, standard rate right turn. Because a standard rate turn is being made, the turn coordinator provides the primary indication of bank performance. The vertical speed indicator is the primary pitch performance instrument because a constant rate climb is being made.
The altimeter and heading indicator serve as secondary pitch and bank instruments and provide the information necessary to know when to roll out of the turn and level off from the climb. As is true of all maneuvers other than constant airspeed climbs and descents, the airspeed indicator serves as the primary power performance indicator. Just as with the other maneuvers, the roll out of the turn should begin when the heading is within one-half of the bank angle of the desired heading, and the leveloff should begin when the altitude is within one-tenth of the rate of climb of the desired altitude (see Figure 12.6).
Figure 12.6. Many things happen at once in a constant rate climbing, standard rate turn.
Table 12.6 presents a typical scan pattern for a constant rate climbing, standard rate right turn. The scan pattern is the same for a constant rate descending standard rate turn.
Try climbing to 5,000 feet at 500 feet per minute in a standard rate left turn to the heading at which you began the turn. If you do this just right, you reach 5,000 feet just as you roll out at your initial heading. Then descend to 2,000 feet at 1,000 feet per minute while turning toward the departure airport. Land and proceed to the next chapter!
|TABLE 12.6 Scan Pattern for Constant Rate Climbing Right Turn|
|Attitude indicator||Right bank sufficient for standard rate turn; nose raised several degrees for 500 FPM climb|
|VSI||Climb rate only 400 FPM|
|Attitude indicator||Raise nose slightly to increase climb rate|
|Turn coordinator||Reflects standard rate right turn|
|Attitude indicator||Maintain bank angle|
|Airspeed||90 knots; maintain power setting|
|Attitude indicator||Maintain bank and pitch|
|VSI||Reflects 500 FPM climb|