Different Types of Turbulence and Their Causes

Turbulence during a flight can cause a lot of unwanted stress for passengers. Whether it is mild or severe, passengers often feel like the aircraft could fall through the sky. Pilots, however, are accustomed to this kind of disturbance mid-flight, and much more. Other than making an announcement, turning the seatbelt sign on, and placing a pause on the airline service trolley, turbulence is no surprising occurrence to pilots and aircrew. In this blog, we will be outlining what turbulence is and the different types of turbulence an aircraft may face.

Turbulence can be defined as the sudden change in airflow, characterized by chaotic eddies and currents of air, which results in bumpy, violent movements. In some cases, it can throw an aircraft off course or force the pilot to devise a strategic plan for landing. There are several types of turbulence including mechanical, thermal, and frontal turbulence as well as clean air turbulence and wind shear.

Mechanical turbulence is caused by the friction between the air and the ground, and it usually occurs at lower atmospheric levels. It largely depends on the strength of the wind and is fueled by unstable air flow. Mechanical turbulence is common for aircraft flying over mountains. Mountains often have turbulent eddies called mountain waves that are found downwind from mountain ridges.

Thermal turbulence is usually the result of the sun's uneven distribution of heat over the earth’s surface. This results in the formation of convective currents, with warm air rising and cold air descending. This kind of turbulence occurs in cumulonimbus or dense rain clouds and can feel quite intense, so pilots avoid flying in these conditions.

Frontal turbulence usually occurs between two opposing air masses such as cold and warm fronts. Though more common with cold fronts, it can also be present near a warm front as well. If the warm moist air is unstable and a thunderstorm develops, turbulence can be particularly severe in some cases.

Wind shear is the variation in wind velocity or direction over a specific horizontal or vertical distance, which results in an intense turning force. It can be categorized as severe turbulence when the horizontal velocity changes 15 m/sec over distances of 1 to 4 km.

Clean air turbulence may be the most surprising type and occurs above an elevation of 15,000 feet in cloud free air. Though rare, it is common during the winter and usually catches the aircrew off guard. In some cases, the aircraft can suffer structural damage, and aircrew and passengers can face injuries if they are moving in the cabin. 

Beyond the different types of turbulence, turbulence can also be categorized as light, moderate, or severe. Light turbulence is defined by slight, erratic changes in altitude. Cups may shake but not spill, and passengers may feel their seat belts tighten. Moderate turbulence has changes in altitude that are more intense where cups may topple over, you may have difficulty moving around, the seat belt sign may come on, and flight attendants may not be able to maneuver their carts. And lastly, severe turbulence, as the name suggests, is the most frightening kind for many people. There may be abrupt changes in altitude and air speed, and the aircrew will likely take their seats and the seat belt sign will remain on. In cases of severe turbulence, upon landing, the aircraft is inspected for structural damage.

If you are faced with any structural damage to your aircraft as a result of turbulence and are in need of aircraft hardware or parts, bearings, fasteners, connector parts, or any other specialized items, ASAP Components has an expansive inventory of over 5 million board-level components. ASAP Components is owned and operated by ASAP Semiconductor LLC, an AS9120B, ISO 9001:2015, and FAA AC 00-56B accredited distributor. Explore our online catalog at your leisure and we invite you to fill out an RFQ form. Once you have submitted the form with details about the parts or components you wish to acquire, we will give you a quote back for your comparisons. Email sales@asap-components.com; we are available 24/7x365.


Recent Twitter Posts


ASAP Semiconductor's Certifications and Memberships

Thank You for Visiting.

We Hope that You Will Visit Us Again the Next Time You Need NSN Parts and Make Us Your Strategic Purchasing Partner.

Request for Quote

We use cookies to ensure that we give you the best experience on our website. If you continue to use this site we will assume that you are happy with it.

 Get A Quote