Ex. 6 – Straight-and-Level Flight

1. Ex. 6 – Straight-and-Level Flight Ex. 6 - Straight-and-Level Flight

2. OBJECTIVE What you will learn: • How attitude and power setting determine aircraft performance • How to use a combination of attitude and power to achieve straight and level flight at desired airspeed. Ex. 6 - Straight-and-Level Flight

3. MOTIVATION Why learn this? • Majority of time spent flying is straight-and-level flight. • May seem like a simple exercise, but becomes not so simple during times of high workload (especially flying in rough air…) • An absolutely crucial skill to get right from the beginning and keep practising to make it almost automatic. Ex. 6 - Straight-and-Level Flight

4. BACKGROUND KNOWLEDGE - TKT Let’s see how much you already know: • What is angle of attack? • What is a trim tab? • What are the three axes and the corresponding movements, and how does the pilot produce and control those movements? Ex. 6 - Straight-and-Level Flight

5. THEORIES & DEFINITIONS Theories & Definitions • Straight-and-Level Flight Definition • Trim • Effects of Power • on pitch (Attitude + Power = Performance) • on yaw • Instruments • Magnetic Compass • how it works, advantages and disadvantages • magnetic dip and compass errors • Heading Indicator. Ex. 6 - Straight-and-Level Flight

6. THEORIES & DEFINITIONS How do you know when flight is coordinated? controlling heading controlling bank controlling yaw controlling altitude controlling airspeed Straight-and-Level Flight: Definition Achieved through a combination of: • steady direction • wings level • coordinated flight • constant altitude • constant airspeed control surfaces movements + power setting Ex. 6 - Straight-and-Level Flight

7. THEORIES & DEFINITIONS What’s its function? How does it do that? Trim Horizontal stabilizer Elevator • Elevator acts like a small wing • It’s hinged onto the horizontal stabilizer, free to rotate around the hinge • Trim tab is a control surface hinged onto the elevator, position set by the pilot • Adjusting trim tab position helps “trim off” control pressures: you won’t have to keep pulling or pushing on the yoke to keep elevators where you want them to be Elevator trim tab Trim wheel Ex. 6 - Straight-and-Level Flight

8. THEORIES & DEFINITIONS Effect of Power: Pitch Airplane is trimmed for a certain angle of attack In straight-and-level flight, a specific angle of attack corresponds to a specific airspeed Plane wants to maintain established airspeed at any power setting Add power  Plane pitches up and starts to climb Reduce power  Plane pitches down and starts to descend Ex. 6 - Straight-and-Level Flight

9. THEORIES & DEFINITIONS What is attitude? What is power? What is performance? Attitude + Power = Performance • Position of the plane with respect to the horizon • nose up or nose down? • level or banked • Controlled by elevators • How much work is the engine doing? • Controlled by throttle • How fast is the plane going? • Climbing, descending or level? How fast is the climb/descent? • Is the plane turning? How quickly? Attitude and power control every aspect of performance together. Ex. 6 - Straight-and-Level Flight

10. THEORIES & DEFINITIONS Why? Effect of Power: Yaw Add power  Plane yaws to the left Reduce power  Plane yaws to the right Fin usually offset to compensate Offset designed for typical cruise configuration Ex. 6 - Straight-and-Level Flight

11. THEORIES & DEFINITIONS Magnetic Compass • requires no external power • simple (nothing to break) • difficult to read in rough air • not reliable in turns or when accelerating/decelerating Lubber line • Compass card • mounted on a pivot • floating in fluid Ex. 6 - Straight-and-Level Flight

12. THEORIES & DEFINITIONS Magnetic Dip Ex. 6 - Straight-and-Level Flight

13. THEORIES & DEFINITIONS Compass Errors: Northerly Turning Error Ex. 6 - Straight-and-Level Flight

14. THEORIES & DEFINITIONS Compass Errors: Acceleration/Deceleration Ex. 6 - Straight-and-Level Flight

15. THEORIES & DEFINITIONS Why? Why? Heading Indicator • works in turns and when accelerating/decelerating • stable, easy to read, intuitive interface • should be reset every 10-15 minutes in straight-and-level flight • more complicated than compass (more to break). Ex. 6 - Straight-and-Level Flight

16. PROCEDURES Procedures • Set Up Normal Cruise • Changing Power • Increasing Power • Flight at New Power Setting • Decreasing Power. Ex. 6 - Straight-and-Level Flight

17. PROCEDURES Set Up Normal Cruise Keep a good look-out! • Set up level flight at desired altitude and use trim wheel to eliminate control pressures • Control yaw with rudder • Keep wings level with ailerons • Reset heading indicator every 15 minutes. Ex. 6 - Straight-and-Level Flight

18. PROCEDURES Why would we want to increase power? Which way will the plane want to yaw? Which way will the plane want to pitch? The new attitude will be more nose -… ? Increasing Power Keep good look-out! • Add power smoothly to estimated power setting • Anticipate and prevent yaw with rudder • Anticipate and prevent pitch change • Retrim the aircraft Ex. 6 - Straight-and-Level Flight

19. PROCEDURES Flight at New Power Setting Keep a good look-out! • Set up level flight at desired altitude and use trim wheel to eliminate control pressures • Control yaw with rudder • Keep wings level with ailerons • Reset heading indicator every 15 minutes. Ex. 6 - Straight-and-Level Flight

20. PROCEDURES Why would we want to decrease power? Which way will the plane want to yaw? Which way will the plane want to pitch? The new attitude will be more nose -… ? Decreasing Power Keep good look-out! • Reduce power smoothly to estimated power setting • Anticipate and prevent yaw with rudder • Anticipate and prevent pitch change • Retrim the aircraft. Ex. 6 - Straight-and-Level Flight

21. CONSIDERATIONS Additional Considerations • Make a habit of trimming • improves flight accuracy/precision • reduces fatigue and workload on the pilot • Never lead with trim • sloppy flying • Use small, smooth control movements • more accurate flying • more comfortable for passengers. Ex. 6 - Straight-and-Level Flight

22. SAFETY What is the procedure? What percentage of time should be spent looking outside? Why? SAFETY: Lookout • Must maintain constant systematic look-out for traffic • Only glance at instruments for brief cross-checking • Vigilant look-out especially critical when flying at nose-up attitudes. Ex. 6 - Straight-and-Level Flight

23. SAFETY What is the range? SAFETY: Power Changes • Power setting will stay within cruise range • Dangers of too much power: • “redlining” the engine • Dangers of too little power: • reduced visibility due to nose-up attitude • loss of airspeed may lead to a stall. Ex. 6 - Straight-and-Level Flight

24. CONCLUSION Conclusion • Flying straight and level is one of the most important and fundamental skills you will learn as a pilot • Even something as seemingly simple as straight-and-level flight requires understanding and mastery of several interdependent controls • As basic as this exercise is, perfection is a challenge! Hold yourself to a high standard from the beginning to keep improving • For next lesson: read Exercise 7 - Climbing QUESTIONS? Ex. 6 - Straight-and-Level Flight