Essay on dragonflies and airplanes, essay on why dragonflies fly low

Dragonfly. Dragonflies vibrate with their wings to create locally unstable air currents that are different from the surrounding atmosphere, and use the vortices created by the air currents to make themselves upward. Dragonflies can soar with very little thrust and can fly not only forward, but also backward and left and right, and can fly forward at speeds of up to 72 km/h.

In addition, the dragonfly flies to fly with only two pairs of wings flapping constantly. Scientists have successfully developed a helicopter based on this structural basis. When flying at high speed, the aircraft often causes violent vibrations, and even breaks the wings and causes a plane crash.

Dragonflies rely on weighted wings to fly at high speeds, so counterweights were added to the wings of the aircraft to solve this thorny problem caused by high-speed flight.

In order to study the aerodynamics of gliding flights and collisions and the efficiency of their flight, a four-bladed, remote-controlled airfoil model was developed and, for the first time, flight parameters were tested in a wind tunnel.

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One summer morning, the sun was shining, I was playing in the yard, suddenly a few dragonflies flew in, I was just about to catch them, some flew to the flowers, some flew to the branches, some flew to the grass.

Yikes! I saw a bigger dragonfly on the branch of the tree, and I walked lightly, and only to hear two "buzz" sounds, a small bee flew over, and I fled in fright. By this time the dragonfly had already flown into the flower bed opposite, and it seemed to say to me proudly

You have the ability to catch me! "I thought to myself not to be too proud to ride a donkey and read the record book—and lo and behold, the dragonfly flew to a flower again, and I was about to catch it, but the bee came sooner or later, and I thought to myself, you're too doggy to take a mouse—nosy!

When I went to look for the dragonfly again, it was long gone! I searched left and right, and finally found it on the branch, and I saw the right moment, and thought: I will definitely catch you this time, I gently reached out and grabbed its wings, I really caught it.

I looked at it carefully, it looked at me pitifully, I thought it was also a beneficial insect, Qingtuan I shouldn't hurt it, I gently let go of my hand, let it go back to the embrace of nature.

That day, the sky was full of dark clouds, and I passed through the park after school and saw a large group of dragonflies flying around, and I wondered why the dragonflies flew so low. It's as if the wings are tied, and you can't fly even if you can't fly. Some of them were still flying around me, and I thought it was fun, so I ran after the dragonflies.

After running for a while, suddenly a few small drops of rain fell, and then it started to rain. The group of dragonflies scurried in the rain and disappeared in three or two clicks. I hurried home, soaking wet.

The next day, it was a sunny day, and I saw dragonflies again. These dragonflies are completely different from yesterday's. Now I see that it is very sensitive, flying high, like a lively child. Compared to yesterday's one, it's like a rebirth.

This kind of doubt is in my mind. Why do dragonflies fly so low when the clouds are thick? Why is it so sensitive on a sunny day?

Is it because it is about to rain, why do dragonflies fly low before it rains? I couldn't figure it out. When I got home, I hurriedly flipped through a lot of books about animals, and finally understood why the dragonflies flew low before it rained.

It turns out that because dragonflies encounter relatively humid air, their wings will be stained with water droplets, so dragonflies fly very low before it rains.

Today, I learned a little more. It seems that only by paying attention to the knowledge in life is everywhere!

Sunday, after lunch. Dad asked me, "Fanfan, shall we go for a walk together?" I jumped three feet high and quickly said, "Okay! Good! Good! ”

My dad and I were scattered in the park, and we were greeted by verdant willow trees, each of which resembled a young girl washing her long hair by the river. The fish in the creek are jumping around, as if they are naughty children. Some swim around in the river, like submarines, and the water is crystal clear.

At this time, we were tired of walking and sat in the gazebo. Suddenly, a flock of dragonflies flew up to me and danced in mid-air, some of them forming a large circle around me and trapping me in as if I were their trophy. At this time, the clouds were thick and it was raining heavily, and suddenly the dragonflies scurried and disappeared into the vast rain.

The next day, after school. I saw a flock of dragonflies flying high above my head, as if they were several small planes. At this time, I wondered why dragonflies fly low on rainy days and so high when the sun is shining.

When I got home and finished my homework, I went to my study to find a book on the secrets of insects. Finally I found it, I opened the book and looked at the table of contents, 107 pages. It turns out that the reason why the dragonfly flies low is that:

Usually before rain, the humidity in the air is quite high, and when dragonflies fly, they tend to wet their wings when they encounter damp moisture; This is the time for dragonflies to catch their prey and prevent raindrops, lightning, and hail from harming themselves. That's why we see the phenomenon of dragonflies flying low.

Through this incident, I learned that if I pay attention to the small events of each thing, I can discover the mystery of it.

Answer: Insects in the humid air, in order to prevent raindrops, hail and thunder from harming themselves, instinctively lower their flight altitude before the rain. Dragonflies, on the other hand, feed on insects, so dragonflies fly low to prey on those insects and fly low as they fly.

Dragonfly, invertebrate, insecta, dragonfly, a common name for insects of the suborder Paraptera. Generally large, the wings are long and narrow, membranous, and the reticulate wing veins are extremely clear. Extremely sensitive vision, 3 in one eye; antennae 1 pair, thin and short; Chewing mouthparts.

Dragonflies are the insects with the most eyes in the world. Dragonflies have large, bulging eyes that occupy most of their heads, and each eye is composed of countless "small eyes" connected to photoreceptor cells and nerves, which can distinguish the shape and size of objects, they have excellent vision, and can look up, down, forward, and backward without having to turn their heads.

Question: Is this true?

Ask a question [powerful].

I discovered the secret of dragonflies flying low It was summer vacation, and the weather forecast said that there would be heavy rain today, so I went out of the house wearing a raincoat and rubber shoes. I came downstairs to a patch of grass in the plaza and saw a flock of dragonflies flying around in front of my eyes. Intrigued, I looked in front of the dragonflies.

Yikes! I felt like I saw a mosquito flying in a circle in front of this group of dragonflies. I thought to myself:

No, mosquitoes fly so low and so slowly, isn't it sent to death? As soon as I thought of this, it began to rain heavily, and I hurried home. As soon as I got home, I hurried into the study and lay down on the table, thinking about the phenomenon of dragonflies flying low in the grass that I had found in the grass today.

Suddenly, my eyes lit up, and I had a way to go back the next day to see if there were any dragonflies flying low. If there is, it is related to rain, and if not, it is a coincidence. The next day, I came to the grass early.

Yes! The day before, the dragonflies were catching pests again, and they were flying very low as usual. I was overjoyed, and it seemed that my guess was correct.

But why is that? I still can't solve this mystery. I wanted to go back and ask my mother, but I wanted to try to solve it myself.

So, I began to observe the dragonflies closely. Hey, there are a lot of mosquitoes flying low, what the hell is going on? Is it that when the mosquito's wings are wet, it can't fly high and can't fly fast?

Do dragonflies fly low just because they want to catch pests? I went home and asked my mother, "Mom, are dragonflies flying low to catch pests?"

A hard work, a harvest. That's a good saying. Not only did I learn this knowledge through observation, but it also made me feel happy.

I love to observe!