E6B Flight Computer
A teaching tool, not a substitute for your aircraft’s flight manual.
This works every answer the way a real E6B works it, so you can follow the steps and check them against your own wheel. It is here to teach the instrument and to help you plan — but it knows nothing about your airplane. Fly the numbers in your flight manual.
Pick a calculation and fill in what you know. It shows the working as well as the answer — and the instrument moves: drag the disc to set the rate, swing the red cursor to read a different pair, drag the red wind dot to plot a different wind, or turn the compass ring to change the course. The numbers follow as you go.
- Heading to fly
- 90°
- Ground speed
- 135 kt
- Wind correction
- none — fly the course
How it works out
- Split the wind about your course of 90°: 25.0 kt along it, 0.0 kt across it.
- The crosswind is what you crab into: sin⁻¹(0.0 ÷ 110) = 0.0° to the right.
- Apply it to the course: 90° + 0° = 90°.
- Crabbing costs you speed along the course, and the tailwind takes 25.0 kt more: 135 kt over the ground.
- Headwind
- 12 kt
- Crosswind
- 14 kt from the right
How it works out
- The wind is 50° off the runway heading of 170°.
- Along the runway: 18 kt × cos(angle) = 11.6 kt headwind.
- Across it: 18 kt × sin(angle) = 13.8 kt from the right.
- Time
- 1:30 hh:mm
- Ground speed
- 115 kt
- Distance
- 172 nm
How it works out
- Distance = speed × time. Rearrange for whichever one you left blank.
- 172 nm ÷ 115 kt = 1.50 hours, which is 1:30.
- Use ground speed, not true airspeed — the wind is already in it.
- Fuel burned
- 23.8 gal
- Endurance
- 2.50 hr
- Burn rate
- 9.5 gph
How it works out
- Gallons = rate × time: 9.5 gph × 2.50 hr = 23.8 gal.
- At 9.5 gph, a 45-minute reserve is 7.1 gal. Carry it on top.
- That is 30.9 gal in the tanks to fly this leg legally by day.
Reserve shown is the day-VFR 30 minutes rounded up to the 45 most pilots plan. Night VFR and IFR need more.
- Pressure altitude
- 9,934 ft
- Density altitude
- 14,094 ft
- True airspeed
- 137 kt
How it works out
- Pressure altitude: (29.92 − 29.92) × 1,000 + 9,934 ft = 9,934 ft.
- A standard day at 9,934 ft would be -4.7 °C. It is 30.0 °C, so you are 34.7 °C above standard.
- Density altitude: 9,934 ft + 120 × 34.7 = 14,094 ft.
- True airspeed: 110 kt ÷ √(density ratio at 14,094 ft) = 137 kt — 24.2% more than indicated.
Above 12,000 ft density altitude a normally aspirated engine is making less than half its rated power. Takeoff roll and the distance to clear an obstacle both roughly double, and the climb may not out-perform the terrain. Consider waiting for the morning.
- Result
- 115.078 SM
How it works out
- 100.000 NM = 115.078 SM.
- On the wheel: set the one value against the other on the outer and inner scales, and every other pair reads off at the same setting.
Why the altitude page matters here
Most Colorado fields are above 5,000 ft, and a warm afternoon puts the density altitude thousands of feet higher still. The airplane does not know what the altimeter says — it flies the air it is in. Leadville on a 30 °C day is above 13,000 ft density altitude, where a normally aspirated engine makes less than half its rated power.
For a field-by-field picture with real temperatures, use the Density Altitude Calculator. To see how far you can actually get in today's wind, use the Range Finder.
