Thermal

Definitions

• A buoyant plume or bubble of rising air.
• A column of rising air associated with adjacent areas of differing temperature. Thermal activity caused by the sun’s heating usually starts 2 to 3 hours after sunrise.

References

• Balloon Flying Handbook, Federal Aviation Administration, 2024
• Glider Flying Handbook, Federal Aviation Administration, 2024
• Powered Parachute Flying Handbook, Federal Aviation Administration, 2007
• Weight-Shift Control Aircraft Flying Handbook, Federal Aviation Administration, 2008