Airworthy Prep

Flight Instructor Airplane test code

AI.X.D.K3Slow flight, Stalls, and Spins: Power-On Stalls

Flight Instructor Airplane test standard, area of operation X, task D

Written as ai.x.d.k3 or AI.X.D.K3 on your score report.

The FAA's wording

Stall characteristics as they relate to airplane design, and recognition impending stall and full stall indications using sight, sound, or feel.

FAA-S-ACS-25, Flight Instructor for Airplane Category ACS (November 2023, effective May 31, 2024), X. Slow flight, Stalls, and Spins, Task D. Power-On Stalls

What it means

AI.X.D.K3 is a knowledge element in the Slow flight, Stalls, and Spins area of operation of the Flight Instructor Airplane test standard. A knowledge element is something the FAA expects you to know, and the written test asks questions on it.

AI
Flight Instructor Airplane ACS
X
Area of operation X: Slow flight, Stalls, and Spins
D
Task D: Power-On Stalls
K3
Knowledge element 3

Seeing it on your score report

Your Airman Knowledge Test Report lists a code for each area where you missed a question. Seeing AI.X.D.K3 there means at least one of your wrong answers was on this element. If you are taking the practical test next, expect the examiner to ask about it. Retaking the written? Start with this code and the others on your report.

Sources: FAA-S-ACS-25, Flight Instructor for Airplane Category ACS (November 2023, effective May 31, 2024); FAA Airman Knowledge Testing Matrix (revised 9/25/26), p. 2.

Can be printed on 2 tests
  • Flight Instructor Airplane (Added Rating) (AFA)
  • Flight Instructor Airplane (FIA)

Got more than one code on your report?

Paste them all into the free study planner and it groups them by subject, most missed first.