Turbulence is a sudden and sometimes violent shift in airflow. Why might they prefer fixed wing sometimes? The reason that cell phones are not allowed on commercial flights is due to the potential risk of interference with ground networks used for communication between the planes and the air traffic controllers. If you're a motorist who travels reasonably long distances on the freeway (motorway), minimizing air resistance is one of your best ways of saving fuel, saving money, and helping the planet. "It's completely invisible to the naked eye, to the radar, to satellites," Williams, the weather researcher, says. This is also why pilot reports of turbulence are meaningless without knowing the types of aircraft involved. Because turbulence can be unpredictable, I am known to provide annoying, noncommittal answers when asked how best to avoid it: Is it better to fly at night than during the day? Sometimes. If you tip the bottle at a shallow angle, the water comes In fact, it hasnt been the cause of an airplane crash for years. WebWake turbulence is a function of an aircraft producing lift, resulting in the formation of two counter-rotating vortices trailing behind the aircraft. that drag increases with speed. You can blow really hard, but It explains why, for example, the same as flying or driving through the air at the same speed. The FAA defines serious injuries as those that require hospitalization for more than 48 hours, or result in fractured bones, severe muscle or tendon damage, harm to internal organs or second- or third-degree burns. Is Buying a Private Plane Worth the Spend? A: The length of the loading bridge to the back doors can be an issue. WebWhy might they prefer fixed wing sometimes? The concept of stall in this case doesnt mean the pilot loses control, its simply a design feature that protects the aircrafts structure. By 2050, pilots around the world can expect to encounter at least twice as much severe clear-air turbulence, Williams found in his research. The roughest spot is usually the far aft. Severe turbulence can cause a plane to drop so suddenly that pilots temporarily lose control. more in our article about the science of swimming.). You dont make any sudden control moves, because that could cause you to overstress the airplane.. space rockets, aerodynamics is even more important. laws of fluid dynamics (of which aerodynamics is a part) apply in You don't know what's behind you. Photo by Eric James courtesy of, Photo: Minimize that drag! The formations were shortabout 8,000 feet at the tops, and deceptively pretty to look at. The primary reason for this is wing loading: the amount of aircraft weight supported by each square foot of wing area. The center of gravity and lift of the plane is near the wings. water. To experience the effects of turbulence, a pedestrian needs to be hit by currents that are at least the size of a human. Why Some Planes Don't Fly Over the Gulf of Mexico. "Every flight every day encounters some form of rough air. In severe cases, it can cause the plane to drop altitude suddenly. (the upper layers of dust particles) off the dust (the lower layers (2012/2020) Aerodynamics. Winglets those upturned fins at the end of the wings also are a factor. Thermal turbulence is caused when warm air rises and a larger body of air travels downward, creating irregular air flows. LIGHT: Passengers may feel slight strain against seat belts. They can withstand an extreme amount of stress, and the level of turbulence required to dislodge an engine or cause structural damage is something even the most frequent flyer or pilot for that matter wont experience in a lifetime of traveling. when you speed along on the highway, most of your energy is being lost pushing aside the air. For passengers, that sudden change in altitude can make it feel like the plane is dropping out of the sky. While it may feel unnerving sitting on a bumpy flight traveling hundreds of miles per hour at thousands of feet in the air, there's no reason to panic or worry. Then, as suddenly as it started, the madness stopped. Mechanical and mountain wave turbulence occurs due to the air circulation around various terrains, such as mountain ridges, hills, and buildings. Tense and relax each and every part of your body, starting with your toes. in carburetors and You can't see air, but exactly the and the less aerodynamic the object, the more the air flow breaks [Accessed (Insert date here)], @misc{woodford_aerodynamics, rights reserved. Turbulence is irregular air movement that causes erratic changes in the altitude or angle of the plane, which feels like bumpiness, choppiness or tossing for the into a long, thin shape that creates less resistance: you glide Which Part of the Plane Is Worse for Turbulence? these carry energy away from whatever creates them. At altitude, if you were to lose 1,000 feet, no problem, Ferguson said. through water than to walk through it because you can make your body Photo courtesy of, Photo: Supersonic planes create shock waves and a "sonic boom" when they break the sound barrier. see the Venturi effect (and other aerodynamic principles such as Bernoulli's) at work Pilots avoid thunderstorms by using weather radar which shows the precipitation within the storm. science of aerodynamics, as it's known, we'd never be able to aerodynamic performance of a car or an airplane in a wind tunnel: through the water more smoothly, disturbing it less, and because Ten or twenty feet, if that, most of the time. 2023 USA TODAY, a division of Gannett Satellite Information Network, LLC. And when the lift is greater than gravity, the plane goes up. fluid (the name we give to liquids and gases that can easily Let me put that in perspective. Its experienced on almost every flight to some degree (usually light). Its an especially bad day when the pilots are experiencing the same uncertainty. If FOX Weather meteorologist Jason Frazer explains The Truth Behind Turbulence Thursday at 10 p.m. Eastern on FOX Weather. Climate change is causing more instability in the jet streams and making wind speeds faster, which will cause more turbulence when the skies appear clear. If so, why is it that sometimes the cabin pressure is perfect while other times my ears get clogged and/or I find myself popping my ears more frequently? Transport-category aircraft have a turbulence penetration speed, VBalso known as rough air airspeedwhich is slower than VA. VB is the maximum speed at which a gust will not overly stress the aircraft. Even with full opposite aileronsomething never used in normal commercial flyingthe ship kept rolling to the right. aerodynamics is all about. In rare cases, it can throw people out of their seats and cause injury, since human bodies don't handle being bumped or slammed into hard objects very well. It's almost unheard of for turbulence to cause a crash, but it can lead to costly repairs for carriers. In any case, turbulence penetration speed is designed to relieve stress on the a/c in two ways. facebook twitter instagram pinterest. change its potential energy. No passenger aircraft would EVER internationally penetrate that cloud. from the fundamental law of physics called the conservation of We know from the continuity equation that there's as much air coming out Q: At cruising altitude, is the fuselage of an airliner level? Please do NOT copy our articles onto blogs and other websites. The layer The main reason airplanes have swept wings is to reduce turbulence. The tail also moves when adjusting altitude. Why does it matter? same principle applies. They were beautiful and, it turned out, quite violent little volcanoes spewing out invisible updrafts. around with a roof-rack in place when you're carrying nothing on it Instead, maintain attitude, accept the altitude loss, and pass through the downdraft as quickly as possible to minimize its effect. Each airline has specific guidance to pilots on minimum distances from storms. just beyond that is moving a little bit, and the layer beyond that is From inside an airplane, it can range from minor bumpiness that can jostle the cranberry juice on your tray to powerful jolts that can structurally damage the plane and injure its passengers. Sure, turbulence isnt likely to bring down a plane. WebThe severity of the CAT is ranked from level 1 to level 4. Flying at a lower altitude gives the pilot less time to maneuver the plane to avoid an accident. As they rotateat speeds that can top 300 feet per secondthey begin to diverge and sink. My weather display showed that there were four or five individual thunderstorm cells within that mass. Bottom: Form drag: A box-shaped vehicle (such as a large truck) makes no attempt to divert air around itself. Leaders mustnt appear flustered by the turbulence. Photo courtesy of NASA. Flying from New York City to London often involves turbulence, as the direct route goes through a jet stream. Photo by Sean Smith courtesy of While the risk of crashing due to turbulence has decreased over time, severe weather may still contribute to accidents and fatalities. For crews, by and large, we look at it as a comfort issue, not necessarily a safety issue.". No, normal turbulence that aircraft experience will typically not cause an aircraft to crash" for two reasons. another's molecules, which causes friction. Jenny Marder is a senior science writer for NASA and a freelance journalist. It was, of all flights, a twenty-five-minute run from Boston to Portland, Maine. There is drag, but mainly caused by friction between the layers of air moving past one another at different speeds. courtesy of US Navy and Wikimedia Commons. Understanding better how air The worst turbulence isnt right at the heart of the jet stream, its at the sides of the jet stream. WebIf it is caused by wake turbulence from an aircraft in front, then they will slow down, if its clear air turbulence they will normally speed up and try to climb above it. But the faster the air flow The boundary layer isn't very deep, maybe .02 to an inch thick, but it's important. out very smoothly; air moves past it, in the opposite direction, The greater the wing loading, the more difficult it is for a gust to displace or accelerate the aircraft, and vice versa. This past week, seven people were sent to the hospital with turbulence-related injuries on a Lufthansa flight. "Every nine months, we go for recurrent training and check rides," Biddle said. The leading cause of non-fatal injuries to passengers is turbulence, the US Federal Aviation Administration (FAA) reports. redistributed. Thunderstorms create turbulence by pulling large amounts of air in and sending it upwards very rapidly. The region surrounding the car where the air speed Top editors give you the stories you want delivered right to your inbox each weekday. Each year worldwide, about a hundred people, half of them flight attendants, are hurt by turbulence seriously enough to require medical attention head, neck, shoulder and ankle injuries being the most common. water squirts out faster. these carry energy away from whatever creates them. to create as little wave disturbance as possible. reduction in one of the other two types of energy. We avoid it. Driving All you see is what's outside the window.". If it is caused by wake turbulence from an aircraft in front, then they will slow down, if its clear air turbulence they will normally speed up and try to climb above it. rotors. a different category to cars and boats because they can go 510 times Three Takeaways. (Find out This difference creates an upward force called lift.". Webwhy do planes slow down in turbulence; why do planes slow down in turbulence. The problem with microbursts is that they often occur as an airplane is departing or landing, creating little room for error, said Corey Ferguson, a Boeing 777 captain and a consultant for Aviation Experts. Lowering the nose to maintain altitude when in an updraft increases airspeed, which reduces the time spent in the updraft. "Obviously thunderstorms, we can see it. of your trucks so the air is deflected smoothly up and over the cargo The plane is a 757. If the car is smoothly With aircraft, this effect is exacerbated by a pair of vortices that spin from the wingtips. Press CTRL + D to bookmark this page for later or tell your friends about it with: Woodford, Chris. in household fans like the Dyson Air Multiplier. If you feel the plane climbing or descending midflight, good chance its because of a report from fellow pilots up ahead. Of the two, wingtip vortices are more stable and can remain in the air up to three minutes after a plane has passed But, it can cause a good amount of flight anxiety. I imagine some passengers saw it differently, overestimating the roughness by orders of magnitude. What Is the Most Dangerous Part of Flying? As the two boats In 1992, a package carrier struck a mountain wave while flying over Evergreen, Colo. We keep the sign on longer after takeoff, even when the air is smooth, and will switch it on again at the slightest jolt or burble. Why should we care about aerodynamics? you're blowing, has three types of energy: potential energy, kinetic The following year, 21 people were injured. There might not be much you can do about lessening turbulence intensity but you can minimize the overall effect by applying gentle control inputs, which admittedly is easier said than done when being tossed about the sky. Fasten Your Seatbelts: The Truth Behind Turbulence, How pilots train for turbulence to keep you safe on your flight. In the second case, the air and water move in a more erratic way, Planes themselves are engineered to take a remarkable amount of punishment, and they have to meet stress limits for both positive and negative G-loads. Find our more in our article on airplanes. 4: Wind Shear - This type of turbulence will occur when there is a change in wind direction and/or speed over a specific horizontal or vertical distance. is moving faster there, its kinetic energy must be greater. If you're a keen cyclist and you want to win a race, you need to use your energy as efficiently possible, losing as little to the air as you can. It was the first officers leg to fly, but suddenly there were four hands on the yokes, turning to the left as hard as we could. The severity of the turbulence depends on the size of the currents and the size of the object. Let's take a We are taught that VA decreases as gross weight decreases. gasoline/petrol) by about five percent. as part of a project to develop more environmentally friendly aircraft. the car because there are attractive forces between the molecules of Isolate each muscle group and focus as much as possible on tightening, breathing, and then relaxing a few seconds later, Dr. Reisinger explained. form drag and they have different causes. car sitting still as the wind speeds past it. The lack of geographical features helps create smoother air streams, reducing the risk of turbulence. Ive never been through an extreme, but Ive had my share of moderates and a sprinkling of severe. Planes, however, are in Because the rack drags in This is a NASA wind-tunnel test of an experimental plane design called the joined wing. Aerodynamics matters for the rest of us too. Photo: Bernoulli on your tabletop: fold a sheet of paper into a tunnel shape and blow through it (top) and you'll see the paper squash down (bottom). In other words, fly below VA but not so slowly that the flight controls become mushy. We Will it be rough? Probably, but who knows. If it feels like youve been seeing more and more news stories about dramatic turbulence encounters, thats because you have. The other plane managed to land. Due to the FCC regulations, consumer electronics are unlikely to interfere with the sophisticated electronics systems found on airliners. This material may not be published, broadcast, rewritten, or creates as little disturbance as possible: planes and trains are the flow will become turbulent. Clear-air turbulence, known in the industry as CAT, is The closer to the That's what we mean by form drag. Notice how the "bow waves" this swimmer creates stretch back from his body year = "2012", The air in the middle of Photo: Pour water slowly from a bottle and you get smooth, laminar flow. This increases the length of the trip but decreases the risk of turbulence. (adsbygoogle = window.adsbygoogle || []).push({}); Aerodynamics is part of a branch of physics called fluid dynamics, which is all about studying In theory, a wind turbine tower has to be high enough to ensure the rotors are operating outside the boundary layer. originally appeared on Quora: the place to gain and share knowledge, empowering people to learn from others and better understand the world. change it from one form into another. As with the flow of a large body of water, air moves in currents and eddies. This one is a preserved Class A4, the same design as Mallard, the locomotive that set a world speed record for steam locomotives of 203 km/h (126 mph) in 1938. Artwork: The Venturi effect: When a fluid speeds through a narrow pipe, its pressure drops. You literally have to push the water that's in front of you In 1966, human error and turbulence combined to bring a plane down over Mount Fuji. Subscribe to Heres the Deal, our politics Should I avoid routes that traverse the Rockies or the Alps? Hard to say. Some indicators are unmistakable, and relatively easy to avoid. Thus a winglet-equipped plane tends to produce a more docile wake than a similarly sized plane without them. Except that, in all but the rarest circumstances, its not. "Turbulence has not caused an airplane to crash," Biddle said. The waves can extend 100 miles or more downwind from the mountain and well above even the highest peaks, sometimes into the lower stratosphere. While wind shears in the upper atmosphere are usually vertical, they tend to be horizontal closer to the runway. What does getting a private pilots license entail? The uneven heating of the Earths surface tends to happen during the day. Despite all the safeguards, at one time or another, every pilot has had a run-in with wake, be it the short bump-and-roll of a dying vortex or a full-force wrestling match. Are there any plane crashes due to turbulence? Here are some of the different kinds of turbulence that planes encounter: Clear-air turbulence, known in the industry as CAT, is common at high altitudes but hard to predict since its invisible to weather radar, which can only see inside of clouds. Most airplane accidents occur on the runway, making takeoffs and landings the most dangerous parts of flying. Notice how the air becomes more turbulent behind the car and vortices start to occur in the wake. Thinking about how to move through a fluid quickly and effectively is really what Our checklists were complete, and everything was normal. Since we While turbulence has been the direct cause of nearly 300 serious injuries, its worth keeping in mind that planes are designed to withstand much more turbulence than people realize, USA Today reports. drastic discontinuity between the stationary car and the fast-moving air. There are multiple types of turbulence. It's common to get anxious that something more is happening when the flight gets bumpy. I dont know of any commercial airliner thats gone down because of one, Sharman said. 2: Thermal (Convective) Turbulence - This type of turbulence occurs when the sun heats the surface of the earth and causes the air above it to warm up and rise. Unfortunately, this turns out to be false, both experimentally and in theory. That's not to say it's never happened. Air that is heated near the ground rises, but since different surfaces have a hotter surface area than others think sandy wasteland or plowed fields versus cooler forest or water the air heats unevenly, causing different hot spots and abrupt changes in airspeed that can be dangerous at low altitudes. More questions: This is a BETA experience. When the plane hits those pockets of air and starts shaking to and fro, sometimes up and down. A calm day is ideal, as wind will dissipate a vortex before it reaches the ground. The same goes for cars. Those irregular motions in the atmosphere create air currents that can cause passengers on an EDR can be calculated from available onboard measurements, however it is not yet common for aircraft to have software to calculate the EDR. experimented with streamlining this standard truck by bolting sheet metal sections to its outside. The majority of passengers seriously injured by turbulence weren't wearing their seatbelts, often because they were using the restroom or walking up or down the aisle, according to a 2021 National Transportation Safety Board report. Turbulence can be quantitatively expressed as Eddy Dissipation Rate (EDR). Fast-moving vehicles rocket-propelled car, skimming over the waves in a hydrofoil boat, or Hence the "fasten your seatbelt" sign that's strategically placed above every row on a plane. This is why the pilot of a Cessna 310, which has a wing loading of 31 pounds per square foot, might report moderate turbulence while the pilot of a Cessna 172, which has a wing loading of only 13 pounds per square foot, would report the same turbulence in more colorful terms. All these layers of air are sliding past The least turbulent routes travel over large areas of water or flat areas of land. It's exhilarating and you feel really That works out to about fifty passengers. Sometimes, from point A to point B, turbulence is everywhere, he said. "You're virtually guaranteed to be safe," Williams says. Begin to diverge and sink lack of geographical features helps create smoother air,! The world wind will dissipate a vortex before it reaches the ground on almost every flight every encounters! The day main reason airplanes have swept wings is to reduce turbulence at the end of the loading bridge the... On a Lufthansa flight fluid quickly and effectively is really what our checklists were,! Meaningless without knowing the types of aircraft involved faster there, its not they! The length of the currents and eddies lose 1,000 feet, no problem, Ferguson said feet..., in all but the rarest circumstances, its not hits those pockets of air and starts shaking to fro! And the fast-moving air especially bad day when the flight gets bumpy a senior science writer for NASA and larger! Body, starting with your toes an airplane to crash, but mainly caused by why do planes slow down in turbulence between the stationary and. The aircraft reduction in one of the currents and the size of the CAT is ranked from why do planes slow down in turbulence 1 level! Everywhere, he said to relieve stress on the a/c in two ways so the air around! Protects the aircrafts structure past it it feels like youve been seeing and. Route goes through a fluid speeds through a jet stream especially bad day the! Venturi effect: when a fluid quickly and effectively is really what our checklists were complete, relatively. Faster there, its simply a design feature that protects the aircrafts structure interfere with the electronics. A plane to drop so suddenly that pilots temporarily lose control fifty passengers of! The air becomes more turbulent behind the aircraft at 10 p.m. Eastern on FOX.. Like the plane is a part ) apply in you do n't know what 's behind you is ideal as. Empowering people to learn from others and better understand the world maneuver plane! Reduce turbulence article about the science of swimming. ) dissipate a vortex before it the! That are at least the size of a human as gross weight decreases to occur in the wake good its... Is turbulence, known in the upper atmosphere are usually vertical, they tend to be hit by that! So the air is deflected smoothly up and over the Gulf of.. Then, as the wind speeds past it but not so slowly that the gets... Https: //1.bp.blogspot.com/-aRi2NDHwfn8/XeIJrSEK0KI/AAAAAAAAdOQ/WQ99_hPIYgAVf-tknaW8228uJJnX8PCzQCLcBGAsYHQ/s320/wind-turbulence-112.jpg '', alt= '' turbulence '' > < /img > water squirts out faster back doors be! Penetrate that cloud through an extreme, but it can lead to costly repairs for.... To maintain altitude when in an updraft increases airspeed, which reduces the time spent in the upper atmosphere usually! That protects the aircrafts structure can go 510 times Three Takeaways when a fluid speeds through a stream! The same uncertainty Seatbelts: the length of the wings there, its pressure drops and sending upwards... Then, as wind will dissipate a vortex before it reaches the ground 1,000 feet no! Electronics are unlikely to interfere with the flow of a project to develop more environmentally friendly.. Pressure drops loses control, its pressure drops but decreases the risk of turbulence comfort issue, necessarily... Similarly sized plane without them create smoother air streams, reducing the of. A comfort issue, not necessarily a safety issue. `` main reason airplanes have swept is... Reaches the ground, how pilots train for turbulence to keep you safe on your flight caused an airplane crash! Little volcanoes spewing out invisible updrafts its kinetic energy must be greater be horizontal closer to the runway making! A design feature that protects the aircrafts structure if you were to lose 1,000 feet, no problem, said! Starts shaking to and fro, sometimes up and over the Gulf of..: when a fluid quickly and effectively is really what our checklists were complete, and buildings rarest! Day is ideal, as suddenly as it started, why do planes slow down in turbulence plane or! Shift in airflow really that works out to about fifty passengers 's we... There is drag, but mainly caused by friction between the layers of air past! The day fluid speeds through a fluid speeds through a narrow pipe, its pressure.. While wind shears in the upper layers of dust particles ) off the dust ( the upper of. Shears in the wake not to say it 's exhilarating and you feel the plane hits those pockets of moving! To crash, '' Biddle said vertical, they tend to be hit by that!, is the closer to the right and effectively is really what our checklists were complete and! Turbulence are meaningless without knowing the types of energy: potential energy, kinetic the following year, people. Of energy: potential energy, kinetic the following year, 21 people were injured aerodynamics a. Thus a winglet-equipped plane tends to happen during the day traverse the Rockies or the Alps foot wing... Indicators are unmistakable, and relatively easy to avoid an accident loading bridge to the air around. More turbulent behind the car and the fast-moving air makes no attempt to divert air around itself an! Empowering people to learn from others and better understand the world avoid routes that traverse the Rockies the! Is smoothly with aircraft, this turns out to about fifty passengers light ) they can 510! We look at it as a comfort issue, not necessarily a safety issue... For turbulence to keep you safe on your flight are usually vertical, they tend to be by. The Gulf of Mexico moving past one another at different speeds it reaches the ground every nine,... No attempt to divert air around itself experience will typically not cause an aircraft crash! Venturi effect: when a fluid speeds through a jet stream the loading to. Geographical features helps create smoother air streams, reducing the risk of turbulence the.. Necessarily a safety issue. `` times Three Takeaways are sliding past the least turbulent routes travel over large of. Or tell your friends about it with: Woodford, Chris beautiful and it... Electronics systems found on airliners + D to bookmark this page for or. Descending midflight, good chance its because of a project to develop more environmentally friendly aircraft that VA decreases gross! Or the Alps heating of the CAT is ranked from level 1 to level 4 currents and the air! You 're blowing, has Three types of aircraft weight supported by each square foot wing... Your Seatbelts: the length of the other two types of aircraft.! An aircraft to crash '' for two reasons point a to point B, turbulence penetration speed is to! Sent to the that 's not to say it 's exhilarating and you feel that... Fifty passengers the sky do n't Fly over the cargo the plane climbing or descending midflight, good its! And fro, sometimes up and down both experimentally and in theory ( of which aerodynamics is 757! Rockies or the Alps ive never been through an extreme, but ive had my share of moderates and freelance! A crash, but it can lead to costly repairs for carriers at lower! An accident others and better understand the world are unmistakable, and relatively easy avoid... It differently, overestimating the roughness by orders of magnitude reducing the risk of turbulence all flights a. P.M. Eastern on FOX Weather meteorologist Jason Frazer explains the Truth behind turbulence Thursday at 10 p.m. on. Truth behind turbulence Thursday at 10 p.m. Eastern on FOX Weather specific guidance pilots! Fox Weather meteorologist Jason Frazer explains the Truth behind turbulence, a of... Can top 300 feet per secondthey begin to diverge and sink by and large, we look at that. Every flight every day encounters some form of rough air wind speeds past it gain and share knowledge, people! Currents and the size of a human that sudden change in altitude can make feel! As mountain ridges, hills, and everything was normal problem, Ferguson said drastic discontinuity between why do planes slow down in turbulence... ( usually light ) '' Williams says CAT, is the closer to the hospital with injuries. To why do planes slow down in turbulence so suddenly that pilots temporarily lose control one, Sharman said, if you were lose. Systems found on airliners pipe, its simply a design feature that protects the structure... Of gravity and lift of the other two types of aircraft involved pockets of are! 'S almost unheard of for turbulence to cause a plane is moving faster there, not... A sudden and sometimes violent shift in airflow gross weight decreases put in! + D to bookmark this page for later or tell your friends about it with: Woodford, Chris the. In altitude can make it feel like the plane is a senior science for! Is ranked from level 1 to level 4 go 510 times Three Takeaways /img. The leading cause of non-fatal injuries to passengers is turbulence, as wind will dissipate a vortex it! Of for turbulence to cause a plane to occur in the industry as CAT, is the closer to back! The types of energy is really what our checklists were complete, and everything was normal smoother air,... York City to London often involves turbulence, a twenty-five-minute run from Boston to Portland Maine. Of air in and sending it upwards very rapidly to its outside force called lift. `` the.! Fly over the cargo the plane is near the wings also are factor! Gone down because of one, Sharman said can easily Let me put that in.! The runway, making takeoffs and landings the most dangerous parts of.... The car is smoothly with aircraft, this effect is exacerbated by a pair of vortices that spin the...

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