AA.II.C.S6
Taxiing (ASEL, AMEL)
What does AA.II.C.S6 mean?
Maintain correct and positive airplane control, proper speed, appropriate use of wheel brakes and reverse thrust, and separation between other aircraft, vehicles, and persons to avoid an incursion/ incident/accident..
- Area of Operation
- II. Preflight Procedures
- Task
- C. Taxiing (ASEL, AMEL)
- Element type
- A Skill element — something you must physically demonstrate to your examiner on the practical test (checkride), not the written.
What you need to know
Taxiing is where many serious accidents (runway incursions, collisions) happen because pilots relax too early — the task tests your discipline in following ATC instructions exactly and cross-checking them against the airport diagram before moving. Watch for confirmation/expectation bias: pilots often hear the clearance they expect rather than the one actually given, so always read back instructions and verify hold-short lines, runway crossings, and any route or runway changes rather than assuming the original plan still applies. Task-manage deliberately — complete checklists fully (not partially, even under distraction), brief the taxi route as a crew if applicable, and slow down or stop rather than guess when uncertain, especially in low visibility where cues are reduced. Ultimately the examiner wants to see you maintain aircraft control, proper speed, and positive situational awareness of other traffic, vehicles, and the airport environment throughout the entire taxi, not just at the start.
Why students miss this
Students tend to treat taxi as a low-workload phase and underestimate how confirmation bias creeps in — they hear what they expect on a taxi clearance (habitual route, usual runway) rather than what was actually said, especially when a route or runway change is issued. This same complacency drives incomplete checklist use and loss of positional awareness during head-down moments like programming avionics or briefing.
Focus on: Practice actively cross-checking every taxi clearance against the airport diagram in real time, especially when anything changes from the expected routing, and treat taxi as a fully crewed, checklist-driven phase rather than a pause between other tasks.
Drill this area until it sticks
AA.II.C.S6 came from a question you missed on the FAA Airline Transport Pilot Multiengine Airplane knowledge test. Drill ACS-aligned practice questions with AI explanations and the cited FAA handbook reference behind every answer — free to start.
Missing it isn't a verdict on you — it's a sign your prep skipped the why behind it. Memorizing answer letters is exactly what leaves gaps like this. Here, every answer explains the reasoning and cites the FAA source it comes from, so the concept holds on test day and at the checkride oral.
Study this concept
Plain-English explanations of the key ideas behind AA.II.C.S6, grounded in the FAA handbooks.
Related ACS codes in C. Taxiing (ASEL, AMEL)
Other elements the FAA tests under this same Task — review them together.
- AA.II.C.R1Distractions, task prioritization, loss of situational awareness, or disorientation.
- AA.II.C.R2Confirmation or expectation bias as related to taxi instructions.
- AA.II.C.R3A taxi route or departure runway change.
- AA.II.C.R4Partial completion of checklist(s).
- AA.II.C.R5Low visibility taxi operations.
- AA.II.C.R6Runway incursion.
- AA.II.C.S1Receive/record taxi instructions, read back/acknowledge taxi clearances, and review taxi routes…
- AA.II.C.S2Use an appropriate airport diagram or taxi chart, if published.
+ 6 more elements in this Task.
Common question
What should I do if I'm not sure I understood a taxi clearance correctly?
Stop the aircraft if needed and ask ATC to confirm or repeat the instruction rather than guessing — clarifying a clearance is always preferable to proceeding on an assumption that could lead to a runway incursion.
What is an FAA ACS code?
The FAA's Airman Certification Standards (ACS) break each certificate into Areas of Operation, Tasks, and specific Knowledge (K), Risk Management (R), and Skill (S) elements. Every knowledge-test question maps to one code like AA.II.C.S6. When you miss a question, your Airman Knowledge Test Report lists its code so you know exactly what to review.
Have a whole list of codes from your report? Paste them all into our free ACS code lookup to see every weak area at once — or browse the aviation glossary for plain-English definitions.