The instrument knowledge test (the Instrument Rating Airplane, or IRA, exam) is the written test for the instrument rating. Like the private written, it is 60 questions and 70 percent to pass, but the material goes deeper into procedures, charts, and weather. Here is how to prepare.
Part of our Instrument Rating guide.
Format and passing score
| Detail | Value |
|---|---|
| Questions | 60, multiple choice |
| Time allowed | 2 hours 30 minutes |
| Passing score | 70 percent |
| Result validity | 24 calendar months (take the checkride within that window) |
What it covers
- IFR regulations (Part 91 instrument rules, currency, alternates)
- Instrument procedures: departures, holds, and arrivals
- Approach charts and how to read and fly them
- Weather: deeper than the private, including icing, fronts, and IFR-relevant products
- Navigation systems: VOR, GPS, and instrument navigation
- IFR flight planning and required equipment
How to get your endorsement
As with the private written, you need a sign-off showing you completed instrument ground training, from an online ground school or your instructor. Then schedule the test at a PSI center using your FAA Tracking Number.
How to study
- Work through an instrument-specific ground school end to end.
- Spend extra time on approach charts and holding, which trip up many students.
- Drill with test-prep software until you score consistently in the mid 80s or higher.
- Take the written before or early in your flight training so the procedures make sense in the airplane.
What you'll need
Instrument written prep from PilotMall.com.
Frequently asked questions
How many questions is the instrument written?
60 multiple-choice questions, with 2 hours 30 minutes and a 70 percent passing score.
Is it harder than the private written?
The material is more procedural and chart-heavy, so most students find it more demanding, but the format is the same.
When should I take it?
Before or early in your instrument flight training, so the procedures and charts make sense when you fly them.