PLT023: Altitude
What code PLT023 covers, why the FAA tests it, and how to study Altitude before your checkride.
Define altitude - absolute / true / indicated / density / pressure
What this means for your checkride
This is the difference between the kinds of altitude a pilot uses. Indicated altitude is what the altimeter reads with the current setting; true altitude is real height above sea level; pressure altitude is height above the standard datum plane; density altitude is pressure altitude corrected for temperature; absolute altitude is height above the terrain below you.
Each altitude answers a different question, terrain clearance, performance, or instrument indication, so the FAA tests whether you can name which one applies and how temperature and pressure move them apart.
Candidates blur true and indicated altitude. On a colder-than-standard day the altimeter reads higher than you actually are, so your true altitude is lower than indicated, which is why cold weather makes obstacle clearance a real hazard.
Where to study it
A code on your test report is an area of deficiency. An authorized instructor must review it with you and endorse that review before you take the practical test, and the examiner may revisit it during the oral. Study it until you can explain it out loud, not just recognize the answer.