Airworthy Prep

Commercial Pilot Airplane test code

CA.IX.C.K2bEmergency Operations: Systems and Equipment Malfunctions

Commercial Pilot Airplane test standard, area of operation IX, task C

Written as ca.ix.c.k2b or CA.IX.C.K2b on your score report.

The FAA's wording

System and equipment malfunctions specific to the aircraft, including:

Vacuum/pressure and associated flight instrument malfunctions.

FAA-S-ACS-7B, Commercial Pilot for Airplane Category ACS (November 2023, effective May 31, 2024), IX. Emergency Operations, Task C. Systems and Equipment Malfunctions

What it means

CA.IX.C.K2b is a knowledge element in the Emergency 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
IX
Area of operation IX: Emergency Operations
C
Task C: Systems and Equipment Malfunctions
K2b
Part (b) of knowledge element 2

Seeing it on your score report

Your Airman Knowledge Test Report lists a code for each area where you missed a question. Seeing CA.IX.C.K2b 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.