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

Ex. 6 - Straight-and-Level Flight 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. OBJECTIVE

Ex. 6 - Straight-and-Level Flight 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. MOTIVATION

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

Ex. 6 - Straight-and-Level Flight 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. THEORIES & DEFINITIONS

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

Ex. 6 - Straight-and-Level Flight Trim THEORIES & DEFINITIONS Elevator Elevator trim tab  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 What’s its function? Trim wheel How does it do that? Horizontal stabilizer

Ex. 6 - Straight-and-Level Flight Effect of Power: Pitch THEORIES & DEFINITIONS 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 Attitude + Power = Performance THEORIES & DEFINITIONS What is attitude? What is power?  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 What is performance?  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 Effect of Power: Yaw THEORIES & DEFINITIONS Fin usually offset to compensate Offset designed for typical cruise configuration Why? Add power  Plane yaws to the left Reduce power  Plane yaws to the right

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

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

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

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

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

Ex. 6 - Straight-and-Level Flight Set Up Normal Cruise PROCEDURES 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 Increasing Power PROCEDURES 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 Which way will the plane want to yaw?Why would we want to increase power?Which way will the plane want to pitch?The new attitude will be more nose -… ?

Ex. 6 - Straight-and-Level Flight Flight at New Power Setting PROCEDURES 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 Decreasing Power PROCEDURES 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. Which way will the plane want to yaw?Why would we want to decrease power?Which way will the plane want to pitch?The new attitude will be more nose -… ?

Ex. 6 - Straight-and-Level Flight Additional Considerations 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 SAFETY: Lookout SAFETY  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. What is the procedure? What percentage of time should be spent looking outside? Why?

Ex. 6 - Straight-and-Level Flight SAFETY: Power Changes SAFETY  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. What is the range?

Ex. 6 - Straight-and-Level Flight 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?