How Can an Airplane Fly? - Part 2
Aircraft Parts in Action
Written by Benjamin Chee, last edited on 1/2/2023
Now that you understand what flaps do, here are some reasons why engineers designed them in the first place.
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Problem: Planes take off and land on short runways, so they need lots of lift at low speed (best achieved with a super large and curved wing) while also being efficient at high speeds in flight (best achieved with a thin, flat wing).
Solution: give planes the ability to change the shape of their wings! Well, not the planes, but the pilots.
An aircraft’s takeoff speed is half or a third of the cruising speed, and these drastically different speeds mean different lifts generated. Much more curvature produces more lift, and a bigger wing means more surface area for lift. When the flaps are extended, they create more drag which is more lift at slower speeds. When the flaps are retracted, they create less drag since there is less surface area for the air particles to interact with, and allows the airplane to fly quickly.
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The complexity of flaps: Smaller flaps create a lot of lift but not a lot of drag, which is best for takeoff, while larger flaps create a lot of lift and drag, which is best for a slow and controlled landing of aircraft.
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Spoilers/speed brakes are located on the top of the wing. They disturb/stop airflow above the wing, which increases resistance on top of the wings, and reduces lift. Ground spoilers deploy when an aircraft touches down on the ground to force weight onto the wheel brakes, increasing the rate that an aircraft slows down while also creating aerodynamic drag.
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Ailerons roll the plane in flight. In a left turn, for example, the right aileron goes down and the left aileron goes up. The high speeds in cruise mean minor deflection causes massive twisting of the wings and quick turning of the aircraft.
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All flight control surfaces are symmetrical so that if one side fails the other will not operate to not create asymmetry and flight control issues.
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We hope you enjoyed our short article! Please email us if you have any questions or want to learn more!
References:
https://www.grc.nasa.gov/www/k-12/UEET/StudentSite/dynamicsofflight.html#:~:text=Airplane%20wings%20are%20shaped%20to,wing%20up%20into%20the%20air.
https://www.nasa.gov/audience/forstudents/k-4/stories/ames-how-do-planes-fly-text.html
https://www.faa.gov/air_traffic/publications/atpubs/aim_html/chap7_section_4.html#:~:text=Wake%20turbulence%20is%20a%20function,and%20direction%20of%20the%20vortices.
https://www.youtube.com/watch?v=67HUcVOAY_0
https://www.youtube.com/watch?v=EmftxGv-yLI
Image Sources:
https://www.fool.com/investing/2020/07/02/report-boeing-to-wind-down-747-production.aspx
https://www.flyingmag.com/ups-receives-delivery-of-its-last-new-boeing-747/
https://www.bbc.com/future/article/20180927-the-boeing-747-the-plane-that-shrank-the-world
https://www.grc.nasa.gov/www/k-12/UEET/StudentSite/dynamicsofflight.html#:~:text=Airplane%20wings%20are%20shaped%20to,wing%20up%20into%20the%20air.
http://www.aviation-history.com/theory/airfoil.htm
https://blog.klm.com/7-remarkable-facts-about-jet-engines/
https://www.lsptechnologies.com/resources/how-do-aircraft-engines-work/
https://www.boldmethod.com/learn-to-fly/aircraft-systems/how-the-four-types-of-aircraft-flaps-work/
https://aviation.stackexchange.com/questions/45392/why-were-the-747sps-trailing-edge-flaps-so-much-different-than-those-of-the-10
https://ultralightdesign.wordpress.com/2017/10/23/all-in-a-flap/
https://www.grc.nasa.gov/www/k-12/airplane/flap.html
https://thepointsguy.com/news/how-airplane-wings-work/