“Fear of flying” is a bit of a misnomer. It’s usually not a fear of flying itself, but of what may go wrong once you’re up there. After all, you’re thousands of feet in the air, in a giant metallic capsule, hurtling through the sky at 500 miles per hour, at the mercy of the elements. Despite all that, you might even forget you’re on a plane at all if not for one annoying (or terrifying) reminder: turbulence.

It feels like the plane is bouncing over a pothole-riddled road. But instead of cursing your city’s public works department, you’re gripping the seat in front of you and holding on for dear life. We all know turbulence is a common part of flying and mostly harmless, but that doesn’t always suppress the visceral gut response of “oh my God, this is it, we’re going down.” On a recent Air Canada flight to Australia, severe turbulence even injured over 30 passengers.

So—is turbulence dangerous? Is the mild heart attack you have every time the plane hits a nasty bump actually justified? We spoke to Mark Baier, CEO and aviation expert at AviationManuals, to get answers to all your turbulence-related questions.

Matador: What exactly is turbulence?

Mark Baier: Turbulence is an area of disturbed air through which an aircraft is flying. When an aircraft wing passes through this disturbed air, it generates inconsistent lift, so that is what commonly causes the “bumpy ride” passengers experience on an airplane.

Some of the most common sources of turbulence are wind shear, the jet stream, weather such as thunderstorms or areas where cold and warm fronts meet, as well as mountains, which can push air up or down.

How can pilots predict turbulence in advance?

Turbulence is hard to predict, but the aviation industry has set up several tools to help pilots better identify potential areas of turbulence. Along with weather forecast sources, the National Oceanic and Atmospheric Administration (NOAA) Aviation Weather Center produces and collects weather reports, forecasts, and pilot reports (information submitted by pilots encountering turbulence), which when put together can help identify the presence of turbulent conditions.

Are there different categories of turbulence? What are they?

Turbulence classification is categorized by intensity and is described as light, moderate, severe, or extreme. The intensity is generally determined by the pilots encountering it based on standardized criteria describing the effect of the turbulence on the aircraft.

Can turbulence actually cause passengers serious harm?

Injury due to turbulence does happen, but it is not generally the turbulence itself. Injuries usually happen because unsecured items in an aircraft hit passengers, or an unbuckled passenger is thrown out of their seat and hits something in the cabin. Even so, serious harm is still rare. The National Transportation Safety Board (NTSB) has had just over 75 reports of crewmembers or passengers becoming seriously injured due to encounters with turbulence during the past 10 years.

Do seat belts actually make a difference in keeping us safe from turbulence?

Absolutely. Injuries due to turbulence are almost always associated with aircraft occupants not wearing their seatbelts at the time of encountering turbulence. It is important for passengers to follow their crew’s instructions to keep their seatbelts fastened at all times during flight, as turbulence may be encountered with little or no warning.

Do some planes handle turbulence better than others?

In general, turbulence tends to “feel” less severe in larger aircraft because of the larger wing surface area. However, that does not make them immune to it. Turbulence can be felt in all aircraft, from the small single-engine hobby plane to the gargantuan Airbus A380.

Can turbulence be powerful enough to bring down a plane?

If an aircraft is in flight at high altitude, there is generally little to no risk of turbulence bringing down a plane on its own. Even when closer to the ground, such as on approach to an airport, there is generally only one type of turbulence, namely wind shear, that in incredibly rare cases can bring down an aircraft. Pilots intentionally avoid these areas, and aircraft technology has advanced to now include tools such as wind shear detection, to further help pilots with avoidance.

Which airspaces around the world get the most turbulence?

There is no specific area of the world that sees the “most” turbulence, since turbulence is highly dependent on weather and local conditions at the time. That being said, flights operating near the jet stream (particularly during the winter months), near convective activity such as thunderstorms, and crossing cold or warm fronts are more likely to encounter turbulence.