Airworthy PrepCommercial Pilot Airplane test code
CA.III.A.K4Airport and Seaplane Base Operations: Communications, Light Signals, and Runway Lighting Systems
Commercial Pilot Airplane test standard, area of operation III, task A
Written as ca.iii.a.k4 or CA.III.A.K4 on your score report.
The FAA's wording
Appropriate use of transponder(s).
What it means
CA.III.A.K4 is a knowledge element in the Airport and Seaplane Base Operations area of operation of the Commercial Pilot Airplane test standard. A knowledge element is something the FAA expects you to know, and the written test asks questions on it.
- CA
- Commercial Pilot Airplane ACS
- III
- Area of operation III: Airport and Seaplane Base Operations
- A
- Task A: Communications, Light Signals, and Runway Lighting Systems
- K4
- Knowledge element 4
Seeing it on your score report
Your Airman Knowledge Test Report lists a code for each area where you missed a question. Seeing CA.III.A.K4 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-7B, Commercial Pilot 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
- Commercial Pilot Airplane (CAX)
- Commercial Pilot Airplane Canadian Conversion (CCP)
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.