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Read the passage and answer the multiple-choice questions.In 1863, the French writer Ponton D'Amecourt was the first person to create the word "helicopter" from the two words "helico" for spiral and "pter" for wings. The very first helicopter was invented by Paul Cornu in 1907, but it was not successful. French inventor, Etienne Oehmichen built and flew a helicopter one kilometer in 1924.However, Igor Sikorsky is considered to be the father of helicopters not because he invented the first. He...
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Read the passage and answer the multiple-choice questions.

In 1863, the French writer Ponton D'Amecourt was the first person to create the word "helicopter" from the two words "helico" for spiral and "pter" for wings. The very first helicopter was invented by Paul Cornu in 1907, but it was not successful. French inventor, Etienne Oehmichen built and flew a helicopter one kilometer in 1924.

However, Igor Sikorsky is considered to be the father of helicopters not because he invented the first. He is called that because he invented the first successful helicopter, upon which further design were based. One of aviation's greatest designers, Russian born Igor Sikorsky began work on helicopters as early as 1910. By 1940, Igor Sikorsky's successful VS-300 had become the model for all modern helicopters of today. He also designed and built the first military helicopter.

Igor Sikorsky's helicopters had the control to fly safely forwards and backwards, up and down, and sideways. In 1958, Igor Sikorsky's company made the world's first helicopter that could land and take off from water. It could also float on the water.

1. Igor Sikorsky invented the first helicopter in the world.

A. True              B. False              C. Not mentioned

2. Who created the word "helicopter"?

A. Igor SikorskyB. Paul CornuC. Ponton D'AmecourtD. Etienne Oehmichen

3. Why was Igor Sikorsky called the father of helicopter?

A. He invented the first helicopter.B. He began his work earlier than other inventors.C. He designed the first successful helicopter.D. He built the first military helicopter.

4. Igor Sikorsky designed VS-300 helicopter model _____?

A. before 1910B. before 1940C. after 1940D. after 1958

5. What made Igor Sikorsky's helicopters successful?

A. His helicopters can fly more than one kilometer.B. His helicopters can fly in all directions.C. His helicopters are cheaper to produce.D. His helicopters can be used as military helicopters

6. On the whole, the passage is about _____.

A. Igor Sikorsky's military helicoptersB. Igor Sikorsky's successful invention of helicopterC. a brief history of helicoptersD. the first helicopter in the world
2
21 tháng 7 2016

1. Igor Sikorsky invented the first helicopter in the world.

A. True              B. False              C. Not mentioned

2. Who created the word "helicopter"?

A. Igor SikorskyB. Paul CornuC. Ponton D'AmecourtD. Etienne Oehmichen

3. Why was Igor Sikorsky called the father of helicopter?

A. He invented the first helicopter.B. He began his work earlier than other inventors.C. He designed the first successful helicopter.D. He built the first military helicopter.

4. Igor Sikorsky designed VS-300 helicopter model _____?

A. before 1910B. before 1940C. after 1940D. after 1958

5. What made Igor Sikorsky's helicopters successful?

A. His helicopters can fly more than one kilometer.B. His helicopters can fly in all directions.C. His helicopters are cheaper to produce.D. His helicopters can be used as military helicopters

6. On the whole, the passage is about _____.

A. Igor Sikorsky's military helicoptersB. Igor Sikorsky's successful invention of helicopterC. a brief history of helicoptersD. the first helicopter in the world
21 tháng 7 2016

1. Igor Sikorsky invented the first helicopter in the world.

A. True              B. False              C. Not mentioned

2. Who created the word "helicopter"?

A. Igor SikorskyB. Paul CornuC. Ponton D'AmecourtD. Etienne Oehmichen

3. Why was Igor Sikorsky called the father of helicopter?

A. He invented the first helicopter.B. He began his work earlier than other inventors.C. He designed the first successful helicopter.D. He built the first military helicopter.

4. Igor Sikorsky designed VS-300 helicopter model _____?

A. before 1910B. before 1940C. after 1940D. after 1958

5. What made Igor Sikorsky's helicopters successful?

A. His helicopters can fly more than one kilometer.B. His helicopters can fly in all directions.C. His helicopters are cheaper to produce.D. His helicopters can be used as military helicopters

6. On the whole, the passage is about _____.

A. Igor Sikorsky's military helicoptersB. Igor Sikorsky's successful invention of helicopterC. a brief history of helicoptersD. the first helicopter in the world
Dịch bài văn sau đây sang Tiếng Việt giúp mình với ( Đừng sử dụng goo dịch nha ) In 1863, the French write Poton D' Amecourt was the first person to create the word ''helicopter'' from the two words ''helico'' for spiral and ''pter'' for wings. The very first helicopter was invented by Paul Cornu in 1907, but it was not successful. French inventor, Etienne Oehmichen built and flew a helicopter one kilometer in 1924. However, Igor Sikorsky is considered to be the father of...
Đọc tiếp

Dịch bài văn sau đây sang Tiếng Việt giúp mình với ( Đừng sử dụng goo dịch nha )

In 1863, the French write Poton D' Amecourt was the first person to create the word ''helicopter'' from the two words ''helico'' for spiral and ''pter'' for wings. The very first helicopter was invented by Paul Cornu in 1907, but it was not successful. French inventor, Etienne Oehmichen built and flew a helicopter one kilometer in 1924.

However, Igor Sikorsky is considered to be the father of helicopters not because he invented the first. He is called that because he invented the first successful helicopter, upon which further designs were based. One of aviation's greatest designers, Russian born Igor Sikorsky began work on helicopters as early as 1910. By 1940, Igor Sikorsky's successful VS-300 had become the model for all modern helicopters of today. He also designed and built the first military helicopter.

Igor Sikorsky's helicopters had the control to fly safely forwards and backwards, up and down, and sideways. In 1958, Igor Sikorsky's company made the world's first helicopter that could land and take off from water. It could also float on the water.

3
12 tháng 7 2017

Năm 1863, người Pháp viết Poton D 'Amecourt là người đầu tiên tạo ra từ' 'trực thăng' 'từ hai từ' helico '' cho xoắn ốc và '' pter '' cho đôi cánh. Trực thăng đầu tiên được phát minh bởi Paul Cornu năm 1907, nhưng nó đã không thành công. Nhà phát minh Pháp, Etienne Oehmichen đã xây dựng và bay trực thăng một năm vào năm 1924.

Tuy nhiên, Igor Sikorsky được coi là cha của máy bay trực thăng không phải vì ông đã phát minh ra chiếc đầu tiên. Ông được gọi là vì ông đã sáng tạo ra chiếc máy bay trực thăng thành công đầu tiên, dựa trên những thiết kế khác. Một trong những nhà thiết kế vĩ đại nhất của ngành hàng không, Igor Sikorsky sinh ra tại Nga bắt đầu làm việc trực thăng vào năm 1910. Đến năm 1940, VS-300 của Igor Sikorsky đã trở thành mô hình cho tất cả các trực thăng hiện đại ngày nay. Ông cũng thiết kế và xây dựng trực thăng quân sự đầu tiên.

Trực thăng của Igor Sikorsky có quyền kiểm soát bay an toàn về phía trước và ngược lại, lên xuống, và đi ngang. Năm 1958, công ty của Igor Sikorsky đã đưa chiếc trực thăng đầu tiên trên thế giới có thể hạ cánh xuống bờ biển. Nó cũng có thể nổi trên mặt nước.

12 tháng 7 2017

In 1863, the French write Poton D' Amecourt was the first person to create the word ''helicopter'' from the two words ''helico'' for spiral and ''pter'' for wings. The very first helicopter was invented by Paul Cornu in 1907, but it was not successful. French inventor, Etienne Oehmichen built and flew a helicopter one kilometer in 1924.

However, Igor Sikorsky is considered to be the father of helicopters not because he invented the first. He is called that because he invented the first successful helicopter, upon which further designs were based. One of aviation's greatest designers, Russian born Igor Sikorsky began work on helicopters as early as 1910. By 1940, Igor Sikorsky's successful VS-300 had become the model for all modern helicopters of today. He also designed and built the first military helicopter.

Igor Sikorsky's helicopters had the control to fly safely forwards and backwards, up and down, and sideways. In 1958, Igor Sikorsky's company made the world's first helicopter that could land and take off from water. It could also float on the water

* Dịch :

Năm 1863, người Pháp viết Poton D 'Amecourt là người đầu tiên tạo ra từ' 'trực thăng' 'từ hai từ' helico '' cho xoắn ốc và '' pter '' cho đôi cánh. Trực thăng đầu tiên được phát minh bởi Paul Cornu năm 1907, nhưng nó đã không thành công. Nhà phát minh Pháp, Etienne Oehmichen đã xây dựng và bay trực thăng một năm vào năm 1924.

Tuy nhiên, Igor Sikorsky được coi là cha của máy bay trực thăng không phải vì ông đã phát minh ra chiếc đầu tiên. Ông được gọi là vì ông đã sáng tạo ra chiếc máy bay trực thăng thành công đầu tiên, dựa trên những thiết kế khác. Một trong những nhà thiết kế vĩ đại nhất của ngành hàng không, Igor Sikorsky sinh ra tại Nga bắt đầu làm việc trực thăng vào năm 1910. Đến năm 1940, VS-300 của Igor Sikorsky đã trở thành mô hình cho tất cả các trực thăng hiện đại ngày nay. Ông cũng thiết kế và xây dựng trực thăng quân sự đầu tiên.

Trực thăng của Igor Sikorsky có quyền kiểm soát bay an toàn về phía trước và ngược lại, lên xuống, và đi ngang. Năm 1958, công ty của Igor Sikorsky đã đưa chiếc trực thăng đầu tiên trên thế giới có thể hạ cánh xuống bờ biển. Nó cũng có thể nổi trên mặt nước

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 38 to 42. HISTORY OF THE HELICOPTER Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a...
Đọc tiếp

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 38 to 42.

HISTORY OF THE HELICOPTER

Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a prototype for the machine that we now know as the helicopter.

Early in the twentieth century, a great deal of experimentation and revision was taking place with regard to helicopter flight. The well-known phrase “two steps forward and one step back” provided an apt descriptor for early flight development. Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft.

On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance. Several models followed without significance until in 1924 when another French pioneer, Etienne Oehmichen, became the first to fly a helicopter for one kilometer. It was a historic flight of 7 minutes and 40 seconds. By 1936, solutions have been found to many of the problems with helicopter flight.

With the introduction of the German Focke-Wulf Fw 61, the first practical helicopter became a reality.

Why was Paul Cornu’s flight important?

A. It was the first practical helicopter flight.

B. It lasted 7 minutes and 40 seconds.

C. It was the first time a helicopter lifted into the air without ground assistance.

D. It was the first time a helicopter lifted into the air.

1
31 tháng 7 2018

Đáp án C


Đáp án nằm ở dòng 1 + 2 đoạn 3: “On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance”

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 38 to 42.HISTORY OF THE HELICOPTERAlthough first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a...
Đọc tiếp

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 38 to 42.

HISTORY OF THE HELICOPTER

Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a prototype for the machine that we now know as the helicopter.

Early in the twentieth century, a great deal of experimentation and revision was taking place with regard to helicopter flight. The well-known phrase “two steps forward and one step back” provided an apt descriptor for early flight development. Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft.

On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance. Several models followed without significance until in 1924 when another French pioneer, Etienne Oehmichen, became the first to fly a helicopter for one kilometer. It was a historic flight of 7 minutes and 40 seconds. By 1936, solutions have been found to many of the problems with helicopter flight.

With the introduction of the German Focke-Wulf Fw 61, the first practical helicopter became a reality.

 

Why was Paul Cornu’s flight important?

A. It was the first practical helicopter flight

B. It lasted 7 minutes and 40 seconds

C. It was the first time a helicopter lifted into the air without ground assistance

D. It was the first time a helicopter lifted into the air

1
14 tháng 12 2017

Đáp án C

Đáp án nằm ở dòng 1 + 2 đoạn 3: “On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance”

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 38 to 42.HISTORY OF THE HELICOPTERAlthough first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a...
Đọc tiếp

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 38 to 42.

HISTORY OF THE HELICOPTER

Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a prototype for the machine that we now know as the helicopter.

Early in the twentieth century, a great deal of experimentation and revision was taking place with regard to helicopter flight. The well-known phrase “two steps forward and one step back” provided an apt descriptor for early flight development. Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft.

On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance. Several models followed without significance until in 1924 when another French pioneer, Etienne Oehmichen, became the first to fly a helicopter for one kilometer. It was a historic flight of 7 minutes and 40 seconds. By 1936, solutions have been found to many of the problems with helicopter flight.

With the introduction of the German Focke-Wulf Fw 61, the first practical helicopter became a reality.

Why was Paul Cornu’s flight important?

A. It was the first practical helicopter flight.

B. It lasted 7 minutes and 40 seconds.

C. It was the first time a helicopter lifted into the air without ground assistance.

D. It was the first time a helicopter lifted into the air.

1
4 tháng 11 2019

Đáp án C

Đáp án nằm ở dòng 1 + 2 đoạn 3: “On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance”

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 38 to 42.HISTORY OF THE HELICOPTERAlthough first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a...
Đọc tiếp

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 38 to 42.

HISTORY OF THE HELICOPTER

Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a prototype for the machine that we now know as the helicopter.

Early in the twentieth century, a great deal of experimentation and revision was taking place with regard to helicopter flight. The well-known phrase “two steps forward and one step back” provided an apt descriptor for early flight development. Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft.

On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance. Several models followed without significance until in 1924 when another French pioneer, Etienne Oehmichen, became the first to fly a helicopter for one kilometer. It was a historic flight of 7 minutes and 40 seconds. By 1936, solutions have been found to many of the problems with helicopter flight.

With the introduction of the German Focke-Wulf Fw 61, the first practical helicopter became a reality.

 

The word “envisioned” in paragraph 1 is closet in meaning to _____.

A. imagined 

B. perfected 

C. experienced 

D. taught

1
14 tháng 9 2018

Đáp án A

Envisioned ≈ imagined: mường tượng, hình dung

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 38 to 42.HISTORY OF THE HELICOPTERAlthough first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a...
Đọc tiếp

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 38 to 42.

HISTORY OF THE HELICOPTER

Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a prototype for the machine that we now know as the helicopter.

Early in the twentieth century, a great deal of experimentation and revision was taking place with regard to helicopter flight. The well-known phrase “two steps forward and one step back” provided an apt descriptor for early flight development. Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft.

On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance. Several models followed without significance until in 1924 when another French pioneer, Etienne Oehmichen, became the first to fly a helicopter for one kilometer. It was a historic flight of 7 minutes and 40 seconds. By 1936, solutions have been found to many of the problems with helicopter flight.

With the introduction of the German Focke-Wulf Fw 61, the first practical helicopter became a reality.

The word “envisioned” in paragraph 1 is closet in meaning to _____.

A. imagined

B. perfected

C. experienced

D. taught

1
17 tháng 10 2018

Đáp án A

Envisioned ≈ imagined: mường tượng, hình dung

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 38 to 42. HISTORY OF THE HELICOPTER Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a...
Đọc tiếp

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 38 to 42.

HISTORY OF THE HELICOPTER

Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a prototype for the machine that we now know as the helicopter.

Early in the twentieth century, a great deal of experimentation and revision was taking place with regard to helicopter flight. The well-known phrase “two steps forward and one step back” provided an apt descriptor for early flight development. Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft.

On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance. Several models followed without significance until in 1924 when another French pioneer, Etienne Oehmichen, became the first to fly a helicopter for one kilometer. It was a historic flight of 7 minutes and 40 seconds. By 1936, solutions have been found to many of the problems with helicopter flight.

With the introduction of the German Focke-Wulf Fw 61, the first practical helicopter became a reality.

The word “envisioned” in paragraph 1 is closet in meaning to _____.

A. imagined         

B. perfected          

C. experienced      

D. taught

1
12 tháng 9 2019

Đáp án A

Envisioned ≈ imagined: mường tượng, hình dung

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 38 to 42.HISTORY OF THE HELICOPTERAlthough first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a...
Đọc tiếp

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 38 to 42.

HISTORY OF THE HELICOPTER

Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a prototype for the machine that we now know as the helicopter.

Early in the twentieth century, a great deal of experimentation and revision was taking place with regard to helicopter flight. The well-known phrase “two steps forward and one step back” provided an apt descriptor for early flight development. Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft.

On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance. Several models followed without significance until in 1924 when another French pioneer, Etienne Oehmichen, became the first to fly a helicopter for one kilometer. It was a historic flight of 7 minutes and 40 seconds. By 1936, solutions have been found to many of the problems with helicopter flight.

With the introduction of the German Focke-Wulf Fw 61, the first practical helicopter became a reality.

What is the topic of the passage?

A. Which aircraft was the first to fly. 

B. Aircraft design in the 20th century.

C. The development of the helicopter. 

D. The invention of the swash plate.

1
5 tháng 2 2018

Đáp án C

Chủ đề của đoạn văn nói về “the development of the helicopter”: sự phát triển của máy bay trực thăng

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 38 to 42.HISTORY OF THE HELICOPTERAlthough first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a...
Đọc tiếp

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 38 to 42.

HISTORY OF THE HELICOPTER

Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a prototype for the machine that we now know as the helicopter.

Early in the twentieth century, a great deal of experimentation and revision was taking place with regard to helicopter flight. The well-known phrase “two steps forward and one step back” provided an apt descriptor for early flight development. Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft.

On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance. Several models followed without significance until in 1924 when another French pioneer, Etienne Oehmichen, became the first to fly a helicopter for one kilometer. It was a historic flight of 7 minutes and 40 seconds. By 1936, solutions have been found to many of the problems with helicopter flight.

With the introduction of the German Focke-Wulf Fw 61, the first practical helicopter became a reality.

 

What is the topic of the passage?

A. Which aircraft was the first to fly

B. Aircraft design in the 20th century

C. The development of the helicopter

D. The invention of the swash plate 

1
24 tháng 7 2019

Đáp án C

Chủ đề của đoạn văn nói về “the development of the helicopter”: sự phát triển của máy bay trực thăng