Flight safety and passenger comfort are pivotal to all Air France operations. Now the airline is going even further, providing pilots with cutting-edge technology for avoiding weather conditions that cause turbulence.
This year, Air France became the world’s first airline to equip its 3,600 pilots with an innovative app that transmits a 4D weather analysis to their connected tablets. Named eWAS (Enhanced Weather Awareness Solution), it displays weather forecasting models of unprecedented accuracy. All over the world, and up until the aircraft doors are closed, crews are informed in real time of any meteorological risks they may face during the flight. Olivier Beghin, an A320 Air France captain, discusses air turbulence and how to avoid it, for Air France magazine.
Captain, can you explain what is widely known as an air pocket?
An air pocket is a myth that can be compared to that of the legendary Bermuda Triangle. There are no pockets in air, just as there are none in water. It’s merely that when an aircraft is in flight, it passes through updrafts and downdrafts that can cause a slight loss in altitude. In most cases, they cause uncomfortable turbulence, but have no impact on the flight.
Can pilots see turbulence?
Cumulonimbus clouds, the storm clouds that cause turbulence, are highly visible, and during the day, we fly around them. At night, or when they are concealed in a layer of clouds, the aircraft weather radar system detects them for us. But certain kinds of turbulence are invisible. To avoid them, we consult the weather displayed by the eWAS app and alter our flight paths accordingly. We also receive messages from aircraft flying ahead of us that have encountered turbulence. Finally, if we cannot avoid an area of turbulence, we reduce the aircraft’s speed to minimize the effects.
Passengers sometimes notice that wingtips move a lot, especially during turbulence. Is this normal?
Absolutely. Wings are designed to bend significantly, thanks to their flexible structure. The wings of an A380, for example, bend upward during flight. The vertical shift at the wingtip can be as much as two to three meters. It’s spectacular, but perfectly normal; wings can flex up to three times this figure.
Can an aircraft be damaged as it flies through an area of turbulence?
No, aircraft are designed to withstand extreme turbulence. There is, however, a considerable risk of falling objects and passenger injury. This is why, for your onboard safety, it’s important to comply with the safety instructions given by the crew.
Is there any wind at the altitudes at which aircraft fly? Is it this wind that causes turbulence?
Yes, of course. Winds increase with altitude and can reach speeds of up to 300 kph. Winds exceeding 150 kph are called jet streams. They are very useful and we often ride them, especially during transatlantic flights, to reduce flight times and fuel consumption. This is why flights from New York to Paris are generally shorter than Paris/New York flights. These jet streams also create turbulence, which we avoid flying through.
Is there more turbulence over mountain ranges?
Yes, for two main reasons. First, there is wave turbulence over mountains. Air at higher altitudes follows the shape of the mountains, creating mini roller coasters as it moves, generating turbulence when aircraft fly through it. Second, mountainous regions create conditions favorable to storm formations. Mountain climbers know this well. The cumulonimbus clouds that form generate strong drafts, which contribute to turbulence.
Can pilots do anything to avoid these areas of turbulence?
Our eWAS weather tool shows crews the areas of turbulence along their route, which means that during flight preparation they can study alternative pathsa highly effective procedure that is often used. Then, once in flight, thanks to the weather radar system in the cockpit, they can adapt their route and change altitude as required, to avoid areas of storm activity. In flying jargon, it’s known as “weather avoidance.”
By providing pilots with better knowledge about weather conditions, Air France can offer its passengers safer and also more comfortable flights, by better anticipating zones of turbulence.
"Wings are designed to bend significantly, thanks to their flexible structure."
© Pages précédentes : Christophe Leroux – Ci-contre : Virginie Valdois - Antoine Akrich/Air France