No pilot launches off a runaway with their fingers crossed. That’s not how we deal with risk.
What I’ve come to realise over the past 10 years as a pilot is that in the eyes of a fearful flyer, the more you know the less you fear.
The reason I wanted to put this together is the shed some light on the scary word… ‘turbulence’ so you will know more and fear less.
Before any of that, if you’ve ever flown on an aeroplane you’ve probably felt it. Whether cruising at 38,000 feet or about to land, it can be a frightening experience as a passenger and the scariest part of flying… but turbulence is no cause for alarm.
It is however extremely important that if we pop the seatbelt signs on you return to your seats and securely fastened your seat belts. I always recommend having your lap belt fastened if you’re in your seat, on the off chance we encounter any unexpected turbulence.
Definition of turbulence- the irregular, chaotic and unpredictable flow of a fluid (like air or water).
So when talking about turbulence on an aeroplane we’re talking about the shaking, the grumbling, the dropping and the lifting caused by the actual turbulent area around it.
This can be caused by a number of things;
Most common turbulence is associated with storms and that is particularly relevant as of the last few weeks across Europe. Bad weather causing delays, cancellations, frustration, re-routing et cetera.
But how does happen and is it dangerous?
This turbulence is a result of water vapour condensing into droplets, when it condenses it releases a tiny amount of latent heat. When this happens a lot you get sudden masses of warm air that rise and then cool and become down drafts. It’s this mixing of the air that is causing what you would feel as turbulence.
This won’t happen to your plane though as your pilot will not fly straight into the heart of a thunderstorm!
We generally give thunderstorms a wide birth and where possible fly up wind to avoid any turbulent air.
How do we see them?
If we’re not able to see them out the window, no problem, we have a weather radar. This paints a range of colours on our screen: green, yellow, red, magenta.
Anything taller than 28,000 ft we plan to avoid by at least 20 miles anything higher than 35,000ft we give a greater margin. We don’t only react to these situations we mitigate the risk at the planning stage and when deciding how much extra fuel to take for delays/rerouting/flying at a different altitude.
Mountain range turbulence-
When wind blows perpendicular to a mountain range it’s forced up and over and then creates this sinal wave like oscillation which you and I feel as turbulence. Imagine a wave breaking over a sandbank this is exactly like that and if you’re the other side of that sandbanks you will experience the turbulence.
Greatest by the rising of hot air over land, common on summer afternoons, flying into places such as Mallorca where the land has heated up throughout the day and so the approach can feel a little rock and roll.
Clear air turbulence- CAT (Common)
This occurs in areas of clear open conditions where one air mass meets another moving at a different speed. The most common culprit here is the cold polar air meeting the warmer air from the south. This produces what you may know or hear over the pilots announcement as a ‘jet stream’ which is effectively a river of air that at its core travels at approx 130 mph or more. Where this meets the slower moving air around it, it can produce lots of eddies of confided air. The rapid change of wind speed and direction is know as windshear. The boundaries of jet streams are always shifting and often exist in beautiful blue skis. Again we have ways to not only manage flying into these but also make use of them and the meteorologists that provide us with our weather charts pre flight do a fantastic job it predicting the altitude and strength and severity of the jet and surrounding turbulence.
A jetstream can knock hours off an Atlantic crossing but be safe in the knowledge that if there’s a smoother route or altitude to be had we’ll sort it. It’s not always possible due factors such as an other aircraft already occupying the space but know that we as pilots much prefer a smooth ride too and will do our best as we talk to air traffic control and other aircraft to find the best route.
Finally, aircraft themselves produce ‘wake turbulence’.
The heaviest slowest aircraft produce the most and as a general rule as pilots we avoid the area below and behind the generating aircraft. This is often why you will have experienced sitting on the runway wondering why you haven’t yet begun the takeoff role. You could be sitting there for 2 min 20 secs behind an aircraft such as the almighty Airbus 380. This can seem like a long time to someone with a fear of flying.
Levels of turbulence (non official)
Light – you may feel a slight strain against your seatbelt, your G&T May begin to creep across the table.
Moderate – similar but now a good service and trying to walk would be difficult. You G&T is definitely on the move. Straw needed.
Severe – the G&T is all over your lap. Walking impossible and you’ve possibly grabbed the arm rest with one hand and the leg of the stranger next to with the other.
The more you know the less you fear.
I hope this brief overview of the different types of turbulence out there has given you the knowledge to understand how it occurs and what we do to avoid and manage it. Above all be safe in the knowledge that at all times you are in incredibly safe hands and we will do everything possibly to make your flight as comfortable as we can. Listen to your cabin crew and to us if we pop that belt sign on.
I hope to see you on a smooth flight soon.