10-year-old Benson, from Rockford, Michigan, wanted to know, “How do airplanes fly?”
Craig Merrett, a professor of Mechanical and Aerospace Engineering at Clarkson University in Potsdam, N.Y., was assigned the task of answering Benson’s question via The Conversation website.
“A force that everyone encounters every day is the force of gravity, which keeps us on the ground. When you get weighed at the doctor’s office, they’re actually measuring the amount of force that your body applies to the scale. When your weight is given in pounds, that is a measure of force.”
This is a great way to explain the force of gravity. Most of us, kids included, can relate to being weighed. Personally, I wish I had a bit less force on the scale.
“You can experience something similar to drag when swimming. Paddle through a pool, and your arms and feet provide thrust. Stop paddling, and you will keep moving forward because you have mass, but you will slow down. The reason that you slow down is that the water is pushing back on you — that’s drag.”
My kids loved swimming in the hotel pool when we traveled. If Benson, or any kid for that matter, has gone swimming, this explanation should make sense.
“The reason why air moves at different speeds around an airfoil remains mysterious, and scientists are still investigating this question,” Craig noted.
Admitting we don’t understand every aspect of flying is important.
Overall, I found the article to be a nice explanation of how airplanes fly. Does that mean I’m a 10-year-old? Mentally, maybe.
Hopefully many more 10-year-olds will be as curious as Benson and make their way into the aerospace industry with the help of Craig’s article.
“If you can’t explain it to a six-year-old, you don’t understand it yourself.” –Albert Einstein, theoretical physicist
“Every great leader has to be a great teacher. Never forget this idea… The mediocre teacher tells. The good teacher explains. The superior teacher demonstrates. The great teacher inspires.” –William Arthur Ward
The wing has to generate a very small pressure difference between the upper and lower surfaces to lift the aircraft.
As an example, my Cessna has 170 sq. ft of wing, which is 24,480 sq. inches.
At a gross weight of 2,350 lb, the wing only needs 0.096 psi lower pressure on the upper surface, to lift the aircraft into flight .[ Bernoulli or not.!? ]
Yes, keep Bernoulli out of it. As Wolfgang says ‘ the explanation is more puzzling than the puzzle ‘ in reference to this.
The pressure difference on your 170 is less than 2 ozs per square inch to keep it up, and most of that comes from the wing upper surface.
In fact at cruise speed or higher most of the lower surface is below ambient static pressure as well.
Very interesting calculations! Thanks to both of you for posting this.
The answer is obvious as to how airplanes fly: Piles of money. Seriously, thanks for General Aviation News and for keeping it mostly civil. That other aviation site is becoming insufferable due to the contest as to who can out-insult whom.
Boogie speaks truth.
I was in an EAA chapter once whose logo was a $100 bill folded into a paper airplane, on fire.
Money makes airplanes fly. All the noise about lift, air pressure, angle of attack, laminar airflow, boundary layers and so on is just sophistry. It is money. With enough money, you could fly Boulder Dam.