Taxiing, Airport Signs, and Lighting (ASEL, AMEL)

To the formalized teaching of safe operating practices during taxi operations. The AFH's language: safe aircraft operations can be accomplished and incidents eliminated if the pilot is properly trained early on and throughout their flying career on standard taxi operating procedures — the flight instructor is the key to developing that teaching. The instructor should instill in the learner an awareness of the potential for runway incursion and emphasize the avoidance procedures (AFH ch. 1). Translation for the checkride: an applicant who taxis well but teaches nothing while taxiing has not met this Task's objective.

A runway incursion is any occurrence at an airport involving an aircraft, vehicle, person, or object on the ground that creates a collision hazard or loss of separation with an aircraft taking off, landing, or intending to land. The three major contributing areas (AFH ch. 1):

• Communications
• Airport knowledge
• Flight deck procedures for maintaining orientation

Those three are also your lesson outline — teach the radio call, teach the diagram, teach the position-tracking habit. And note the AFH's warning that many flight training activities are conducted at non-tower controlled airports, where the absence of a tower creates a need for increased vigilance.

Make the plan a spoken product, not a private intention. Before releasing the brakes the student:

1. Has the airport diagram out and in view at all times — the AFH's first listed taxi procedure (AFH ch. 2).
2. States the expected route aloud, including which runways will be crossed.
3. Identifies the Hot Spots on the route. Hot spots are designated on the airport diagram, and the geometry they mark is real — PHAK's worked example is Taxiway Bravo intersecting Runways 31-13 and 35-17, which themselves cross, a combination that can be very confusing and create navigational challenges (PHAK ch. 14).
4. Reviews the complete taxi plan even at a familiar airport. The AFH's reasoning is precise: a pilot given the same taxi instructions repeatedly starts expecting those same instructions and might not realize they no longer apply — it only takes missing one instruction or turn to generate an accident.

Mechanically it's a slip — an error of action, where a person plans to do one thing and inadvertently does another. The AIH's own example is a taxi/runway case: a pilot assigned runway 30 for many days is assigned runway 12, and out of habit turns to enter the pattern for runway 30 (AIH ch. 3). It is a change in routine, which is one of the conditions under which errors are known to happen.

Training against it, using the AIH's own error-reduction methods:

• Using reminders — write the clearance down; a written route is a visible reminder actively used.
• Developing routines — a standardized readback and a standardized "confirm before turn" call.
• Raising awareness — teach the student to flag the moment itself: "this is different from last time" out loud.
• Taking time — hurrying increases slips through the speed-accuracy tradeoff. A student under time pressure at the hold line is a student about to make one.

Four yellow lines across the full width of the taxiway — two solid, two dashed — painted where taxiways intersect runways, in alignment with and collocated with the holding position sign (PHAK ch. 14).

• Approaching the runway you see the two solid lines first. Stop before them and ensure no portion of the aircraft intersects the first solid yellow line. Do not cross the double solid lines until a clearance from ATC has been received.
• Exiting the runway you approach the double dashed lines. To be clear of the runway, the entire aircraft must cross both the dashed and the solid lines. No ATC clearance is needed to cross this marking when exiting.

At a nontowered airport or when the tower is closed, you may taxi onto or across the runway only when the runway is clear and there are no aircraft on final approach — with extreme caution, looking both ways.

The sign itself — white characters outlined in black on a red background, the numbering conventions, and the surface painted version — is covered under Task II.C. Teach the appearance on the ground; this Task is about what happens when the airplane is moving.

The consequence is the part to state without softening: noncompliance with a runway holding position sign — or marking — may result in the FAA filing a Pilot Deviation against you (PHAK ch. 14). Never allow any part of the aircraft to cross either the vertical sign or the surface painted marking without an ATC clearance — not the nose, not a wingtip.

How that turns into instruction while taxiing:

• Make the student say it, not just see it — require a verbal call at every hold short line, "holding short of 27, no clearance", from the first taxi lesson. A student who narrates cannot drift through one while distracted, and distraction is how it happens
• Stop the airplane before you discuss anything — if the student is confused about which sign applies, brakes first, then talk. Sorting it out while rolling is the actual incursion mechanism
• Your intervention criterion: if the airplane is still moving inside the last aircraft-length before the line and the student hasn't begun to stop, you say "stop" — a single word, not a question — and take the brakes if it doesn't happen immediately. There is no coaching opportunity worth a runway incursion

This is also the clearest place in primary training to apply the law of primacy: whatever the student does at a hold short line on the first three lessons is what they'll do at every hold short line for the rest of their flying.

From PHAK ch. 14:

• Taxiway edge lights — blue, omnidirectional, outlining the taxiway edges; many have variable intensity adjustable by ATC or on pilot request.
• Taxiway centerline lights — green at airports that have them.
• Clearance bar lights — three in-pavement steady-burning yellow lights at holding positions, to increase conspicuity in low visibility or mark an intersecting taxiway at night.
• Runway guard lights — at taxiway/runway intersections, either a pair of elevated flashing yellow lights on either side of the taxiway or a row of in-pavement yellow lights across the entire taxiway at the runway holding position marking. Note: some airports have a row of three or five in-pavement yellow lights at taxiway/runway intersections that should not be confused with clearance bar lights.
• Stop bar lights — a row of red, unidirectional, steady-burning in-pavement lights across the entire taxiway at the holding position, plus elevated steady-burning red lights on each side, used to confirm an ATC clearance to enter or cross an active runway in low visibility (below 1,200 ft RVR). Operated with taxiway centerline lead-on lights: after the clearance, the stop bar goes off and the lead-on lights come on, and both are automatically reset by a sensor or backup timer.

RWSL, the REL/THL distinction, and the inference students invert are covered under Task VI.A — teach the system there. The one line to carry into the taxi lesson: the lights are red, they indicate runway status only, and they do not indicate clearance (PHAK ch. 14). A dark REL is not a clearance.

What's specific to taxiing is that RWSL is not installed at most airports, so you have to decide what you're training. If you instruct at an RWSL field, the risk is that students build the habit on the lights and lose it the first time they taxi somewhere without them. Train the clearance discipline as primary and treat the lights as a backup that happens to be present — never the reverse.

Teach the reason, then the rule, then the check. From AFH ch. 2:

• Quartering headwind — hold aileron into the wind (upwind aileron UP). Moving the aileron up reduces the effect of the wind striking that wing, reducing lifting action; the downwind aileron goes DOWN, producing a small amount of lift and drag on the downwind wing that further reduces the upwind wing's tendency to rise.
• Quartering tailwind — elevator DOWN and upwind aileron DOWN, reducing the tendency of the wind to get under the tail and the wing and nose the airplane over.
• Nosewheel airplanes hold the elevator neutral with moderate to strong headwinds and strong slipstream; tailwheel airplanes hold it full aft to keep the tail down, moving toward neutral only when the headwind gets very strong.
• Applying these corrections also minimizes the weathervaning tendency and results in easier steering — which is the argument that convinces students, because it's about control, not ritual.

Make it stick by requiring the student to state the wind source before the airplane moves and to re-state it after each turn. Position without perception is the error.

From the visual wind indicators, and this is a knowledge element in its own right — you are expected to teach the hardware, not just the control positions. From PHAK ch. 14:

• Wind cone / wind sock — the best of them, because it gives direction and lets the pilot estimate velocity and gust factor: it extends out straighter in strong winds and moves back and forth when the wind is gusting.
• Wind tee and tetrahedron — these swing freely and align themselves with the wind, but either can also be manually set to align with the runway in use, so a pilot should look at the wind sock for wind information if one is available. The tetrahedron's small end points in the direction of landing, and pilots are cautioned against using it for any purpose other than landing direction; at a towered field reference it only when the tower is closed, because tower instructions supersede tetrahedron indications.
• Segmented circle — the visual indicator system these usually sit in, made up of wind direction indicators, landing direction indicators, landing strip indicators, and traffic pattern indicators.

The teaching point students miss: even where a CTAF broadcast exists, there is no assurance the information provided is accurate, so PHAK says check the indicators anyway. Make "look at the sock" a spoken item before taxi, then have the student predict the control positions from what they saw.

Separate element, separate lesson, and it starts before taxi:

• Anti-collision lights ON at all times before engine start; for night operations the position (navigation) lights should also be on (AFH ch. 2). Teach it as the signal to everyone outside that the propeller is about to turn — paired with "CLEAR" out the side window and a wait for a response.
• Position lights are arranged like a boat's: red on the left wingtip, green on the right, white on the tail (AFH ch. 11). Worth teaching on the ground because it is the same knowledge the student will use to resolve traffic in the air.
• At night the pilot should turn the rotating beacon ON or flash the position lights to alert people nearby to remain clear of the propeller — but the AFH is explicit that this supplements, not replaces, a careful methodical scan around the aircraft.
• After starting and when ready to taxi, turn the taxi or landing light ON. The limits the AFM/POH will tell you about: continuous landing-light use while taxiing can place an excessive drain on the electrical system, and some landing lights overheat from inadequate cooling airflow, so the landing light may be used only if necessary.
• Don't blind other pilots — the AFH says so directly, and it's the courtesy item that separates a taught student from a self-taught one. Kill the landing light when facing a run-up area or an airplane on final for the parallel.

Then teach the airborne extension in the same breath: landing lights on within 10 miles of an airport and below 10,000 feet, day or night and in reduced visibility, and in areas where flocks of birds may be expected (AFH ch. 11).

The brake check — brakes tested for proper operation as soon as the airplane is put in motion. Technique: apply power to start moving forward slowly, retard the throttle, and simultaneously apply just enough pressure to one side, then the other, to confirm proper function and reaction of both brakes. If braking performance is unsatisfactory, the engine should be shut down immediately (AFH ch. 2). The ACS makes it a skill element (AI.V.D.S5), and the reason it's first is that you still have room to stop by other means.

Not a number — a set of capabilities. The primary requirements for safe taxiing (AFH ch. 2):

• Positive control
• The ability to recognize any potential hazards in time to avoid them
• The ability to stop or turn where and when desired, without undue reliance on the brakes

Operationally: speed should be at the rate where movement of the airplane is dependent on the throttle — slow enough that when the throttle is closed, the airplane can be stopped promptly. Proceed at a cautious speed on congested or busy ramps.

Related habits to teach in the same breath:

• Retard the throttle immediately once the airplane begins moving, since more power is needed to start moving than to keep moving.
• Other than sharp turns at low speed, the throttle should always be at idle before the brakes are applied; it is a common error to taxi with a power setting that requires controlling taxi speed with the brakes.
• Slow down before a turn — sharp high-speed turns place undesirable side loads on the gear and may cause tire damage, an uncontrollable swerve, or a ground loop. Swerves are most likely turning from a downwind heading toward an upwind heading.

Same three steps, adapted to a phase where both people can reach the controls (AIH ch. 9):

1. Instructor tells, instructor does — you taxi, narrating: the wind source and your control positions, why you're looking where you're looking, the sign you just passed and what it means, the hold line coming up.
2. Student tells, instructor does — the student calls the route, the signs, and the control positions while you steer. This is where you find out they think blue lights mark runways, at zero cost.
3. Student tells, student does — the student taxis and verbalizes. Your feet stay near the brakes.

Two AIH cautions apply hard here. With potentially hazardous maneuvers the instructor should be alert and ready to take control at any time, especially on a first attempt. But if a learner is progressing normally, the instructor should avoid unnecessary interruptions or too much assistance — a student who is never allowed to correct their own centerline drift never learns to.

• Riding the brakes. Named by the AFH as a common error — taxiing with a power setting that requires the brakes to control speed. Correction: set the throttle so closing it stops the airplane, and call out "throttle idle" before any brake application.
• Head down. When taxiing, the pilot's eyes should be looking outside the airplane, scanning from side to side while looking both near and far to assess routing and potential conflicts (AFH ch. 2). Correction: assign the scan out loud, and take the diagram away briefly if it has become a fixation object.
• Wandering off centerline. The AFH wants the yellow centerline stripe visually placed under the center of the fuselage, because some taxiways have above-ground taxi lights and signage that could strike the airplane or propellers without accurate control.
• Reading back a clearance without hearing it. Correction: write it, then read it back — the ACS wants clearances received and correctly read back (AI.V.D.S1).
• Continuing when uncertain. The rule the AFH gives: if at any time there is doubt about safe clearance from an object, stop the airplane and check the clearance — it may be necessary to have the airplane towed or physically moved by a ground crew. Extend the same rule to position: unsure where you are, stop clear of the runway and ask.

The realistic list, and the answer to each:

• Add power in a turn and load the gear. Your hand stays near the throttle whenever the student's is.
• Taxi across a hold line while looking at the diagram. Your intervention point is before the solid lines, not at them — brief a mandatory full stop short of every hold line, every time, and take the airplane if it isn't slowing.
• Turn the wrong way onto a runway on a clearance to cross a different one. Mitigate by requiring the student to state the runway designation on the sign out loud before crossing.
• Freeze under a controller's rapid-fire instruction. You take the radio, not the airplane — and you brief in advance that you may.
• Taxi into an obstruction they can't see from the left seat. Your wingtip clearance judgment is the one that counts; if in doubt, stop.

The governing limit is the AIH's: learners should never be allowed to exceed the flight instructor's limits, and instructors should not exceed their own ability to perceive a problem, decide upon a course of action, and physically react (AIH ch. 9).

Everything gets slower and more procedural. Brief:

• Diagram in hand and route pre-stated, because visual cues that carried the student in daylight are gone.
• The lighting system as the primary navigation reference — blue taxiway edge lights, green centerline lights where installed, yellow clearance bars and runway guard lights, red stop bars.
• Clearance bar lights specifically, since they exist in part to indicate the location of an intersecting taxiway during periods of darkness (PHAK ch. 14).
• Airport lighting control: at towered airports ATC controls it; at nontowered airports lights may be on a timer or, at selected airports, pilot-controlled by keying the microphone on a specified frequency — 7 clicks within 5 seconds for highest intensity, 5 clicks within 5 seconds for medium or lower, 3 clicks within 5 seconds for lowest available. Pilot-controlled lighting availability is published in the Chart Supplement (PHAK ch. 14).
• A stop-and-ask threshold, agreed in advance, so that being lost is a briefed outcome rather than an embarrassment.

• Runway guard lights exist primarily to enhance the conspicuity of taxiway/runway intersections in low visibility, but may be used in all weather conditions.
• Clearance bars increase conspicuity of holding positions in low visibility.
• Stop bar lights confirm an ATC clearance to enter or cross an active runway in low visibility — below 1,200 ft RVR — and are the one system where the light state is tied to a clearance you were already given.
• RWSL warns, but does not clear.

The limit to teach: none of this substitutes for knowing where you are. Airport knowledge is one of the three contributors to runway incursions (AFH ch. 1), and lights only help a pilot who already has a position fix.

Stop the airplane clear of intersections and rebuild the plan out loud. Concretely:

• Re-read the new clearance from what they wrote, not from memory.
• Re-identify hot spots on the new route — the old ones no longer apply.
• Re-state which runways will now be crossed, and confirm each crossing is explicitly cleared.
• Reload takeoff data if the runway changed: length, surface, wind components, and the emergency plan for the takeoff briefing, which is runway-specific (see Task V.F).

The instructor framing is that this is the highest-value teaching moment on the whole taxi, because it's the exact condition — a change in routine — under which the AIH says errors are known to happen (AIH ch. 3). Name it as such to the student while it's happening.

The instrument cross-check, for free. Taxiing checklists are sometimes specified by the AFM/POH, but if there are no specific items, taxiing still provides an opportunity to verify the operation and cross-check of the flight instruments (AFH ch. 2). What should be true:

• Airspeed at or near zero, depending on taxi speed, wind, and lower limit sensitivity
• Attitude indicator showing pitch and roll level, no flags
• Altimeter indicating the proper elevation within prescribed limits
• Turn indicator showing the correct direction of turn, with the ball moving toward the outside of the turn, no flags
• Directional gyro set and cross-checked against the magnetic compass, verified accurate to the direction of taxi
• VSI reading zero

This works on conventional mechanical instruments and on glass. Teaching it during taxi builds the habit at no cost in flight time, and it catches the failed instrument on the ground.