PLT056: Horizontal Situation Indicator
What code PLT056 covers, why the FAA tests it, and how to study Horizontal Situation Indicator before your checkride.
Interpret information on a Horizontal Situation Indicator (HSI)
What this means for your checkride
The horizontal situation indicator combines the heading indicator and the VOR or localizer course display in one instrument. A course pointer set to the desired course, a deviation bar, and the heading under the lubber line let you see course and heading together, which reduces reverse-sensing errors.
The HSI is common on instrument panels, so the FAA tests how to set and read it and how it differs from a separate CDI and heading indicator.
Pilots forget to set the course pointer to the front course, inviting reverse sensing. Setting the HSI course arrow to the inbound course makes the deviation bar sense correctly.
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.