Several incidents where airline passengers needed medical attention have turned the attention to the problem of severe in-flight turbulence. In recent months, Singapore Airlines Ltd., Qatar Airways and Air Europa flights have suffered sudden drops in altitude. This resulted in passengers needing hospital treatment as well. In late May, Singapore Air Flight SQ321 encountered severe turbulence as it entered Thai airspace triggering an emergency landing in Bangkok. The flight was en route to Singapore from London.

Turbulence is on the rise and in recent times, severe air turbulence has even caused death and serious injury (Shutterstock)

This week, forty passengers were injured when an Air Europa flight hit severe turbulence on its way from Madrid to Montevideo in Uruguay. As per turbli database, most turbulent flights of all connect Santiago in Chile to Santa Cruz in Bolivia. Flights leaving Tokyo dominate the list of the roughest long-haul services as per the website. The website produced its rankings by analyzing 150,000 routes using data from UK and US government meteorological agencies.

Strong turbulence is produced when air streams traveling at significantly different speeds come together- typically encountered at the boundaries of jet streams, over mountains and in certain cloud storms, as per turbli website.

The website said that turbulence on the Santiago-Santa Cruz route is generated by winds from the Pacific Ocean to the Atlantic Ocean flowing almost perpendicular to the Andes. The equator is also a well-known region for turbulence.