### Introduction Now that we've covered all the elements of planning a cross-country trip, it's time to talk about the things that can go wrong.  Inadvertent flight into [[IMC]] is one of those things. Inadvertent VFR flight into IMC is a real danger, especially due to unexpected weather, or flying at night.  Without spatial references, the average untrained pilot will lose control of the airplane within minutes.  Therefore, the pilot must learn to control the plane solely by reference to instruments long enough to return to visual conditions. **Pre-Lesson Reading/Homework:** [[~ PPL Pre-Lesson Reading]] **Builds On:** [[PPL1.2 Four Fundamentals of Flight]] **Schedule:** Ground 0.5 hr, Sim/Flight 1.0 hr Practice on multiple flights > [!note] > Can be completed at the same time as [[PPL5.3 Emergency Operations]]. ### CFI Equipment Hood or foggles ### Lesson Elements **The General Approach** 1. Relax - to think more clearly, and to feel the flight control pressures 2. Don't trust your senses.  The vestibular sense (motion sensing by the inner ear) will generate false sensations and fool the pilot.  Trust the instruments. 3. Execute a continuous Instrument Scan (See below) 4. Trim for level flight, and use fingertip control.  Resist the urge to over-control.  Experiment with letting go of the controls, watching the airplane's behavior, and correcting with trim. 5. Use autopilot if available. 6. All turns, climbs, and descents should be very gradual (no more than 10° bank, 2.5° pitch up or down) 7. Read [[IFH]] Chapter 7 for more pro tips **The Continuous Instrument Scan** 1. Control/performance instruments vs. primary/supporting instruments 2. Attitude Indicator - the most important instrument 3. Instrument cross-check, types of scans 4. 4-step scan procedure (Butcher) to initiate any maneuver 1. Set approximate attitude and power 2. Inverted V-scan to check trends 3. Scan primary instruments 4. Scan all instruments **Scenarios of Particular Concern for Accidental IMC** 1. Accidentally flying into a cloud -- turn around! 2. Accidentally trapped above a cloud layer -- go elsewhere to VFR conditions 1. If unable to go elsewhere, with ATC's help/instructions, establish stable, slow descent through layer **Attitude Instrument Flight Basics** 1. Straight and Level flight ([[IFH]] 7-2) 1. Set appropriate engine power and pitch attitude. 2. Continuous scan, returning to the attitude indicator after each other instrument 3. Interpret results, make adjustments 2. Straight climbs and descents (IFH 7-14) 1. Avoid combining these with turns 1. To climb: 1. Power-pitch-trim 2. Scan continuously 2. To descend 1. Pitch-power-trim 2. Scan continuously 3. Turns (IFH 7-19) 1. Don't combine with climb/descent-- too complicated 2. Aim for a standard-rate turn 1. How to check this on your avionics? 3. On roll-in, use instrument scan to maintain altitude 4. Be aware of compass errors: [[NOSE]] etc. **Common errors** 1. Spatial disorientation (see [[Illusions Leading to Spatial Disorientation]]) 2. Distraction 3. Fixation or omission 4. Multitasking in a turn -- watch the turn, and do nothing else until complete 5. Heavy touching, over-controlling 6. Improper trim control ### Completion Standards Client must demonstrate basic attitude instrument flying skills, to ACS standards. Maneuvers will include straight-and-level, turn to headings, and perform constant airspeed climbs and descents, by reference to flight instruments only. Concurrent tasks will include looking up and tuning radio and navigation frequencies. > [!success]- Tolerances (Partial) from [[Private Pilot ACS|ACS]] > ±200', heading ±20°, airspeed ±10 knots ### Resources - Instrument Flying Handbook ([[IFH]]) Ch 6-7; - [[Private Pilot ACS]] Sections VIII.A,B,C,D,F ### Required Homework None ### Recommended Homework - [ ] Chair fly four fundamentals using image of instruments. What do you expect to see changing in each for each maneuver? *Return to [[~ PPL Lesson Plan Outline|Table of Contents]]^*