Have you ever wondered what it means when turbulence is reported as moderate vs. light? When you're making a pilot report, how should you classify the type of turbulence you're flying through? You're about to find out...

(Pay attention to the key words in bold for you next flight)

Light Chop

Slight, rapid, and somewhat rhythmic bumpiness without any noteworthy changes in altitude or attitude. Imagine this as driving a boat over a small wake and the kind of small, rhythmic bumps you might expect.

Light Turbulence

Momentary, slight erratic changes in altitude and/or attitude. You might feel a slight strain against your seat belt or shoulder straps. While small unsecured objects might become dislodged, it'd be easy to walk around the cabin with little or no difficulty.

Moderate Chop

Moderate chop is similar to light chop but more intense. It consists of consistent bumps or jolts, with little to no change in altitude or attitude. It feels like driving a boat across white caps on a windy day.

Moderate Turbulence

Changes in altitude/attitude occur, but the aircraft remains in positive control (in your control) at all times. You'll feel a definite strain against seat belts or shoulder straps. Unsecured objects will become dislodged and walking will be difficult.

Severe Turbulence

Large, abrupt changes in altitude or attitude will occur. The aircraft may be temporarily out of control. Walking is impossible and occupants will be forced violently against their seat belts. It's caused messes like this on commercial aircraft:

Extreme Turbulence

The aircraft is violently tossed about and practically impossible to control. Extreme turbulence might cause structural damage or even break apart the airframe. The airplane below flew into a squall line and experienced extreme turbulence, resulting in a mid-air break up.

Reporting Terms

Turbulence frequency is important to report as well. Here are the three types of frequency you can report with turbulence.

• Occasional - Less than 1/3 of the time.
• Intermittent - 1/3 to 2/3 of the time.
• Continuous - More than 2/3 of the time.

Turbulence accounts for roughly 75% of all Part 121 airline weather-related accidents. Understanding how it's reported, and reporting to ATC when you experience it, is pretty important.