Aircraft Flight Controls and Operation of Systems

Ailerons, elevator (or stabilator), and rudder produce movement about the three axes (PHAK ch. 6):

The instructor-depth part is the coupling. Ailerons produce adverse yaw — the down-going aileron makes more lift and therefore more drag, so the airplane yaws opposite the bank — and this worsens at low airspeed just as rudder authority weakens (PHAK ch. 6). Teach the rudder as the anticipated correction for the aileron input, not the reaction to the ball.

Flaps, trim devices, and (where installed) leading edge devices, spoilers, and slots. The teaching points:

• Flaps increase lift and drag, permitting a steeper approach angle without an increase in airspeed and reducing stall speed (PHAK ch. 6). The instructor-depth follow-up: the first increment buys mostly lift, the last increments buy mostly drag, so teach why the POH schedules flaps the way it does rather than "flaps 10 on downwind." Extending flaps also changes the trimmed pitch attitude at a given airspeed, which is why the student's picture over the nose moves on every configuration change.
• Trim relieves control pressure at a given airspeed; it does not fly the airplane. Teach "pitch for airspeed, power for altitude, trim to hold what you set," and correct the student who trims to an attitude rather than after establishing one.
• Anti-servo tab on a stabilator increases control force as deflection increases, giving the pilot the feel a stabilator would otherwise lack.

Then tie it to the design: differential ailerons and Frise-type ailerons exist specifically to reduce adverse yaw by increasing drag on the up-going wing (PHAK ch. 6).

Start with the energy path — fuel and air in, controlled combustion, power out — then attach each control and each gauge to a point on that path. In a fixed-pitch trainer that is mixture and throttle; in a complex airplane it is throttle, propeller, and mixture, and the order of operations on power changes becomes a real limitation.

Instructor-depth items students ask about:

• Why lean? Mixture must be adjusted for density altitude; too rich wastes fuel and fouls plugs, too lean raises temperatures.
• Mag check RPM drop — expected on a normal check, and why a zero drop is also a discrepancy
• Carburetor ice — when to expect it and what the initial indication is in a fixed-pitch versus constant-speed installation.
• Constant-speed propeller — the governor holds RPM; a blue knob change is a change in blade angle, not a throttle.

Everything above must be confirmed against your POH before you teach it.

Fixed gear: the failure modes are tires, brakes, and shimmy. Retractable gear: the list grows — hydraulic or electric actuation, the squat switch, gear position indication, the emergency extension procedure, and the airspeed limits VLO and VLE from the POH.

Instructor risk item: the gear-up landing is a distraction accident, not a knowledge accident. Teach a positional flow with a verbal call ("gear down, three green, pressure normal") at the same two points in every pattern, and enforce it from the right seat even when you are busy teaching something else.

The path from tank to cylinder: tanks, selector, strainer/sumps, pump(s), and the engine-driven pump. Then:

• Fuel selector management — which position feeds what, whether "BOTH" exists, and any POH limitation on takeoff and landing tank selection
• Unusable fuel — the gauges read to zero, the tanks do not
• Sumping — what water and what the wrong fuel grade look like, and why you sump after every refueling
• Contamination and fuel grade — the color coding, and why the wrong grade or jet fuel is a preflight-detectable disaster

Every number — capacity, usable fuel, unusable fuel, pump operation — comes from the POH for the airplane you are teaching in.

It powers convenience in a day-VFR trainer and survival at night or in IMC. Teach:

• Alternator/generator and battery
• Master switch — its master and alternator halves
• Bus structure and circuit breakers
• Ammeter or loadmeter — which way the needle moves on your airplane for a charging versus discharging condition

The instructional payoff is the failure drill: recognize the indication, reduce load, follow the POH checklist, and land while you still have the equipment you need. AI.II.E.R1 and R2 are exactly this — detection of the malfunction, then management of it.

Three instruments, one system (PHAK ch. 8 principles):

• Blocked pitot, drain open — airspeed drops toward zero
• Blocked pitot with the drain also blocked — the airspeed indicator behaves like an altimeter: reads high in a climb, low in a descent
• Blocked static — altimeter freezes, VSI reads zero, airspeed is inaccurate; the alternate static source (or, in an unpressurized airplane, breaking the VSI glass) restores a static reference, usually with a slight indication error because cabin pressure is lower than ambient

For vacuum/pressure-driven gyros: teach the failure as insidious rather than sudden — the attitude indicator degrades slowly and lies convincingly, which is why the partial-panel scan and the suction gauge check exist.

The management problem, not the button sequence. Teach three levels of automation and the discipline to drop down a level when the airplane is not doing what you expect:

• Full automation
• Flight director / heads-down navigation
• Hand-flying with raw data

Concrete instructor rules:

• Verify what the box is doing — mode annunciation, active leg, altitude preselect — out loud
• Program on the ground, or in level cruise, never on the approach
• If the automation surprises you, disconnect and fly first, diagnose second

AI.II.E.R4 flags the paired risk: providing instruction in unfamiliar aircraft, or with unfamiliar flight display systems and avionics. If you do not know the box, you cannot supervise a student using it.

• Environmental — cabin heat in most trainers is exhaust-heated air through a heater muff, which is why carbon monoxide is a winter risk in the airplane you fly weekly (see Task II.A).
• Deice — removes ice after it forms (boots, weeping wing depending on installation)
• Anti-ice — prevents it from forming (heated pitot, prop heat, hot windshield panels)

The teaching point that matters more than the hardware: known-icing capability is an authorization, not a description of what the airplane can survive, and a trainer with a heated pitot tube has no icing capability at all.

• Oxygen — covered in depth in Task II.N: continuous flow, diluter demand, pressure demand, and pulse demand systems, their altitude limits, and the 91.211 requirements.
• Water rudders (ASES, AMES) — retractable control surfaces on the back of each float, extended downward into the water for directional control while taxiing, attached by cables and springs to the air rudder (FAA-H-8083-23 glossary). Retracted for takeoff and landing; see Task II.L.

A repeatable four-step pattern that works for every sub-element in K1:

1. Purpose — what problem does this system solve? One sentence.
2. Path — trace it physically. Fuel from tank to cylinder, air from inlet to instrument, electrons from alternator to bus. Draw it; a student who can draw it can troubleshoot it.
3. Controls and indications — what the pilot touches and what the pilot reads, tied to points on the path.
4. Failures — what the indication looks like, what the POH says, and what the student does.

This is the demonstration-performance explanation phase (AIH ch. 5): the learner should be intellectually ready before the demonstration, and the explanation should cover the safety procedures before the doing starts. Finish by having the student teach it back to you at the airplane with their hand on the actual control — that is AI.II.E.S1.

Because a checklist only helps a pilot who has correctly identified the problem. The whole value of system knowledge is the detection step named in AI.II.E.R1 — a rough-running engine, a slowly failing attitude indicator, a discharging ammeter, and a blocked static port each present as a symptom that the student must map back to a system before the checklist becomes relevant.

Teach the mapping explicitly. Give the student the indication and ask for the system, then the system and ask for the indication. Then run the checklist.

Decide in advance who does what and brief it. A workable division:

• Student flies, instructor manages on first exposure to a real (not simulated) abnormality
• Positive three-step exchange of controls whenever the roles change (AIH ch. 9)
• Simulations are announced as simulations, and simulated failures are never introduced in a phase of flight where the real thing would be unrecoverable

For multiengine work, AFH ch. 13's rule is the model: no engine failure is introduced below VSSE, and if no VSSE is published, use VYSE. Extend the principle: no simulated failure at an altitude or configuration from which the recovery has not been briefed.

• Real control inputs. Pulling the actual control creates the actual failure. A mixture cut, a fuel selector to OFF, or a real master switch off may not restore promptly. Simulate with the throttle or with a verbal statement wherever possible, and know the restoration procedure before you touch anything.
• Forgetting to reset. The student solves it correctly and you forget to reset. Build a "restore and verify" call into the debrief-in-flight.
• Compound failures. Simulating one thing while a real second thing is happening is how training flights become emergencies. If anything about the airplane is abnormal, cancel the simulation.
• Distraction from the primary duty. You are still responsible for see-and-avoid, terrain, and airspace while the student runs a checklist.

Two gates, and both must open.

Legally:

• Category and class rating on both your flight instructor and pilot certificates (61.195(b))
• A type rating on your pilot certificate for any aircraft requiring one, including for instrument training (61.195(e))
• 5 hours of PIC time in the specific make and model before giving training required for a certificate or rating in a multiengine airplane, helicopter, or powered-lift (61.195(f))

Practically, AI.II.E.R4 names instruction in unfamiliar aircraft or with unfamiliar avionics as a risk in its own right. Meeting the regulation is not the same as being able to detect a system abnormality one second before the student does. Get the training, fly the airplane, learn the box — then teach.