Comprehensive Study Guide
Top of Descent (TOD) & Glidepath Study Guide
Master the 3-to-1 distance rule, Ground Speed FPM multiplier (5 rule), shock cooling avoidance, and ear comfort.
Editorially reviewed by the AviCalculator team
1. Professional Descent Math
Managing descent profiles trades potential energy for forward airspeed smoothly.
- TOD Distance (NM): TOD = Altitude to lose in thousands of feet × 3.
- Descent Rate (FPM): FPM = Ground Speed in knots × 5.
- Cabin Comfort Rule: Keep unpressurized cabin descents below 500 FPM to prevent painful Eustachian inner ear blocks.
Test Your Knowledge
You've reviewed the theory. Now apply it to real FAA/EASA checkride questions to verify your understanding.