English article introduced by D.B. Cooper

Modern transportation extends in all directions. Planes, trains, cars and ships can take us anywhere we want. Since the plane appeared, the dream of human beings spreading their wings and soaring in the blue sky like birds has finally come true. By air, we can not only travel around the world, but also greatly shorten the journey time. In today's air transport, Boeing 727 undoubtedly plays an important role. It stands out among many types of commercial aircraft with its superior performance and comfortable environment, and constantly satisfies people's desire for flying. But its design is also improved step by step in the continuous flight practice. For example, the Cooper switch installed at the tail of the aircraft was invented to make up for the defects in the previous design.

Before 1970s, the gangway at the tail of Boeing 727 plane descended from the engine room, which provided a good platform for emergency skydiving. At that time, other types of commercial aircraft did not have this condition. However, the hijackers took advantage of this feature of Boeing 727 and successfully hijacked the plane twice. Later, in order to prevent similar hijacking from happening again, designers redesigned the gangway at the exit of Boeing 727, installed a device that could prevent the gangway from being put down during the flight, and named it "Cooper switch".

Now, all Boeing 727s are equipped with Cooper switches. There is a little-known story about the motive of inventing this switch. The name "Cooper switch" itself has an unusual origin.

I. Mysterious passengers

On April 7th, 1972, United Airlines Flight 855 started its long-distance flight across the United States from new york to Los Angeles as usual. On the way, Boeing 727 will make a short stop at Stapleton International Airport in Denver, Colorado to carry more passengers.

The plane's crew includes captain Gerald Hearn, co-pilot Kent Owen and flight attendant Diane Pearcey. These six people took the same flight many times and got along well.

Captain hearn is the oldest of the crew. He is calm and experienced in flying, and he is not surprised when things happen. He is deeply trusted by everyone. Co-pilot Owen also has many years of flying experience. He is straightforward and helpful, and young flight attendants regard him as their big brother. Diane is the head waiter of a flight attendant. She has thick black hair, a pointed chin and nose, thin lips, a thin face, sunken eyes and thick eyelashes, which gives people a very smart feeling, as well as at work. Every time she flies, she can finish her work very satisfactorily. Passengers who often take her flight know that if they encounter problems on the plane, they can get a satisfactory solution by looking for Diane. No, as soon as the plane landed smoothly at Stapleton International Airport, she and several other flight attendants were busy preparing for the passengers who boarded the plane halfway.

After everything is ready, passengers begin to board the plane.

The first people to board the plane were a prison guard and a prisoner in handcuffs. They first boarded the plane through a special passage. The prison guard is about 30 years old, dressed in casual clothes and with a serious expression. The prisoner is a burly middle-aged man with a hooked nose and a gloomy face. He is a fugitive, arrested by the police outside Denver, and now he will be taken back to San Quentin prison. At that time, plane passengers were usually tourists or business people, but this way of escorting fugitives was also very common, so the crew was not surprised.

After the prison guard and the fugitive boarded the plane, according to the regulations, the prison guard opened the handcuffs of the fugitive, but never left his side. Like other passengers, Diana smiled and led them to the left of aisle 20, the last row of seats on the plane. This position is perfect for escorting fugitives. It is not only economical and safe, but also avoids causing tension among many passengers.

The escaped prisoner is in the room and the prison guard is outside. After the two sat down, other passengers began to board the plane. At that time, the security level on the plane was very low. Passengers and their luggage can board the plane without metal detectors and X-ray inspection. In case of an accident, the crew have to solve everything themselves, so they must be careful everywhere. When the passengers stopped boarding, the crew began to make final preparations before taking off.

Diana checked from front to back along the aisle of the cabin. While checking the number of people boarding the plane, she checked the placement of passengers' belongings and whether passengers were sitting in the right position, reminded passengers to fasten their seat belts and answered questions from individual passengers, which was meticulous and thoughtful.

When Diane walked to the back of the cabin, she found that the seat on the right side of the 20 rows of aisles, that is, 20-D, was empty, so she asked the passenger sitting in the 20 rows of window seats, "Sir, is this seat taken?"

The passenger by the window is a middle-aged man with glasses. He is absorbed in a thick book in his hand and can see at a glance that he is a scholar. After hearing Diana's question, he looked up at Diana, looked at the seat next to him and said, "I don't know, I've been reading." I remember this position was empty when I came up. "

"Oh, thank you!" Diana thanked her and went to the left of the aisle to have a look. The guards and fugitives sitting there are all right. Diana looked back at the empty seat on the right side of the road again, feeling very strange. Ticket sales records at the airport show that the ticket for this position has been sold; The boarding record also shows that the ticket holder in this position has boarded the plane. And I walked all the way from the front of the cabin and didn't find anyone sitting in the wrong position. Where the hell did this passenger go?

Diane was thinking about it when the escaped prisoner waved to her and pointed to the bathroom. Diane nodded knowingly and went to the bathroom.

The restroom is next to the aisle behind the 20th row. Diane came to the bathroom door and found a sign above the door that said someone was in the bathroom. Diane felt very strange, because if someone is in the bathroom, the plane can't take off. Usually, few people go to the bathroom at this time.

Diana knocked on the bathroom door and asked, "Is anyone in there?"

No one answered.

"Is there anyone inside?" Diana asked again, but no one answered.

Diana put her ear to the door and listened. There was no sound inside, so she gently pushed the door with her hand. Obviously, the door is locked from the inside, which further proves that there is someone inside.

"Someone in it? Please hurry, the plane is about to take off. " Diana asked again, but there was still no answer. Diane suddenly became nervous. Did something happen?

Just as Diana was about to report to the captain, the bathroom door suddenly opened from the inside and a man with long hair and a moustache came out. He is wearing a black suit with a white shirt and a black tie inside. Judging from his clothes, he looks like a business person, but strangely, he wears a pair of wide-brimmed sunglasses in his eyes and a pair of black leather gloves on his hands, which is out of place with business people's clothes and looks strange. Diane has been a flight attendant for a long time. She has seen many passengers with strange clothes and strange behaviors, but this is the first time to see such a strange person. She was shocked for a moment.

The passenger walked out of the bathroom without saying anything, and went straight to the position of 20-D and sat down.

"Hey, what happened ..." The escaped prisoner cocked his head, and his eyes moved with the eccentric passengers, muttering something.

"Be quiet, don't look around!" The prison guard sitting outside the escaped prisoner ordered. The escaped prisoner glanced at the prison guard, turned over and was silent.

After this sudden incident, Diane and other flight attendants checked the cabin again. After verifying that everything was correct, Diane picked up the microphone and began to broadcast the flight precautions. After everything was ready, the plane took off.

Diane always felt that there was something wrong with the passenger in seat 20-D, so she looked up the passenger register and found that the passenger's registered name was J. Johnson. Like other passengers, he bought a one-way ticket in cash. At that time, credit cards were not popular, and passengers could buy air tickets without showing any photo identification, so in the event of an accident, it was difficult to determine the true identity of passengers. "I hope everything is safe!" Diane kept on serving the passengers as usual while chanting in her mind.

The plane flies in the blue sky and white clouds like a big bird. The passengers in the cabin are very quiet. Some people dozed off in the back of the chair. Some people look out of the window and think quietly. Some people will invite flight attendants to come and look through magazines. The long flight made the passengers look listless. Diane and other flight attendants constantly patrol the cabin in order to solve the problems or difficulties encountered by passengers in flight in time.

Diane visited the cabin again when the plane flew over the Rocky Mountains. She started from first class and walked back in rows. A passenger was thirsty. She brought drinks. A passenger fell asleep and the magazine in his hand fell to the ground. She helped pick it up. Just then, a male passenger came in a hurry from the back of the cabin. He looked around and then stood beside Diana. He quietly tugged at Diane's skirt. Diana looked up. It turned out to be a middle-aged scholar sitting on the right side of row 20 by the window. He looked flustered, his eyebrows were locked, and a little sweat had oozed from the tip of his nose.

What can I do for you? Diana asked kindly.

Middle-aged scholars did not answer. He looked around gravely, then leaned over Diana's ear and whispered, "The man next to me, that man …"

Seeing that the man was incoherent with nervousness, Diane comforted him and said, "Don't be nervous, speak slowly."

The middle-aged scholar swallowed and said as low as possible, "The man next to me has a Grenade ..."

"What?" Diana was taken aback and looked at the middle-aged scholar with her mouth wide open, but she immediately realized that she was rude. Diane looked around at the passengers, but fortunately, no one paid attention to her.

In order not to disturb other passengers, Diana took the middle-aged scholar aside and asked softly, "What's going on?"

The middle-aged scholar took a deep breath and whispered in Diane's ear: "I was reading a book just now, and the person next to me suddenly unfastened his seat belt and bent down to take the suitcase under the seat to his knee." I glanced at him and saw him open the suitcase and take out a Grenade! Then he turned his head to me. He is wearing sunglasses. I can't see his eyes, but I can feel his eyes staring at me behind my glasses. It seems that he showed it to me on purpose ... Could he be the hijacker? "

"Did you really see it? Is that really a Grenade? Maybe a toy or something ... "

Before Diane finished, the middle-aged scholar interrupted her: "No, I won't make a mistake. It's really a Grenade. I have seen it. "

The voice of the middle-aged scholar was very excited. Diane put her finger to her mouth and said, "Shh, don't tell!" " "

Diana glanced at the hut. The passengers sat quietly in their seats. Some people are closing their eyes, some are reading newspapers, and some are looking at the white clouds floating outside the window. Nobody pays attention to them. Diane leaned close to the middle-aged scholar's ear and whispered, "I'll report to the captain and we'll take care of this." Don't go back to your seat, I'll arrange another seat for you. Remember, keep it a secret and don't disturb others. "

The middle-aged scholar nodded and said, "I know."

Diana put the middle-aged scholar in an empty seat in the first class, then immediately went into the cockpit and reported the situation to the captain Gerald Hearn.

After listening to Diana's report, Captain Hearn didn't show any panic. He frowned and was silent for a moment, then asked Diana in a very calm tone, "Could that passenger be mistaken?"

"I don't think so. I have long thought that the man in the 20-D seat is a bit odd. " Then Diana told what happened before the plane took off.

"Will he want to hijack the plane?" Co-pilot Kent Owen guessed.

Hearn didn't speak.

"Do you want to report to the ground?" Diana was a little anxious and didn't know what the captain was thinking.

Hearn hesitated for a moment and said, "well, don't worry, wait until you figure out the situation." Diane, you go to explore the truth and report to me. Remember, don't disturb other passengers and don't show panic yourself. Let's go "

Diana nodded and left the cockpit in a hurry.

Diana adjusted her breath, calmed her mood, walked down the aisle to the back of the cabin, and served the passengers as if nothing had happened. However, before she finished her first class, she was stopped by a male passenger coming on. The passenger has gray hair and wears a dark green coat. Diane recognized him as a passenger in row 19.

What can I do for you? Diana asked with a smile.

The man didn't answer. He handed Diane a big white envelope with a straight face, and Diane reached out and took it. At the moment of receiving the envelope, Diane felt the man's hand shaking slightly, and she had a sense of foreboding.

Diana glanced at the surface of the envelope, and a frightening line immediately jumped into her eyes and nailed her there like a nail. There is a line printed on the envelope: "The pull ring of the Grenade has been pulled out, and the pistol is full of bullets."

Diana paused for a moment, then immediately recovered from the shock. She asked in a low voice, "What the hell is going on?" In fact, nine times out of ten, she has guessed it.

The passenger put it in Diana's ear and whispered, "The man in sunglasses behind me asked me to give this envelope to your flight attendant, and then you transferred it to the cockpit."

Diana asked, "Who is wearing sunglasses? Is it the one sitting in the 20-D seat? "

The passenger nodded his head.

Diane immediately realized the seriousness of the matter. She put the passenger in first class, told him to keep quiet, and then hurried into the cockpit with an envelope.

As soon as Diana entered the cockpit, Owen quickly asked, "How did you come back so soon? Did you see the Grenade with your own eyes? "

"Oh, not yet. Before I walked out of first class, a passenger stopped me and said that the man in seat 20-D asked him to give us this envelope. " Diana said, handing the envelope to Hearn.

Captain Hearn took the envelope and frowned at once. Obviously, he has seen the printed words. The envelope is not sealed. Hearn opened the envelope and took out a folded piece of writing paper from it. The writing paper is hard inside, as if it were wrapped in something. Hearn opened the letter paper and a label fell out.

Owen lost his voice and shouted, "It's the pull ring on the Grenade!"

Hearn picked up the bill and looked at it carefully. He said, "Well, it was really pulled from a Grenade, but I can't tell what model it is."

Hearn handed Owen the label and unfolded the writing paper. The contents of the letter are also printed and written in detail. The writer asked the plane to turn to San Francisco and land at San Francisco airport. Even the specific runway is clearly written, and it is required that no vehicles should be parked within the plane 100 yard. In addition, he also asked for $500,000 in cash and four parachutes, and asked for six hours of fuel for the plane. All these must be delivered to the airport when the plane lands.

At the end of the letter, it said, "We have grenades, pistols and C-4 plastic explosives. If we don't do it, we'll blow up the plane! Don't disclose the news to other passengers. After reading this letter, be sure to return the original. "

Hearn read the letter, handed it to Owen, and said heavily, "It seems that we really met a robber!" " "

In recent years, hijacking has become a common occurrence in the United States. From 1967, as far as Hearn knows, there have been at least 100 hijackings. Turn on the newspaper and TV, and you can often find this news. Some hijackings are carried out by terrorists for a certain political purpose, while others are a means for fugitives to extort money; Some hijackings can be properly solved, while others cause a large number of passengers casualties, even the crew members are not spared. The last thing a pilot wants is a robber on the plane he is flying. Hearn has been a pilot for 10 years and has never encountered such a thing. He always felt lucky, but he didn't expect such a thing to happen to him today. The lives of six crew members and nearly 100 passengers are in the hands of robbers. As long as he gives up, the consequences are unimaginable. And he is the owner of a machine. How to deal with this matter depends on his own decision. He suddenly felt an unusually heavy burden on his shoulders. If this matter is not handled properly, not only nearly 100 passengers and other crew members will worry about their lives, but also they themselves will be in born to die. ...

Just as Hearn was thinking about how to deal with this matter, Owen suddenly cried, "hmm?" Why do I feel that this matter is so familiar? "

Hearn and Diane immediately focused on Owen. Owen took the letter, read it several times, and then said, "Do you know about a hijacking that happened about four months ago? A man named D.B. Cooper hijacked a Northwest Airlines plane and then demanded ransom and parachute with pre-printed instructions ... "

Hearn patted his forehead and said, "I know about it. I have read relevant reports. This man named D.B. Cooper later released the passengers and left with a parachute. The police haven't caught him yet ... Well, the requirements of the robbers are really similar to his ... "

"So what should we do now?" Diana looked at Hearn and Owen with expectation and trust.

"The security work at the airport is too inadequate. The robbers actually took grenades and pistols on the plane!" Owen looks very angry. Hearn stopped him and said, "We need to calm down. Now is not the time to discuss this. " Owen fell silent.

Hearn turned to Diana and said, "You should return the letter at once, and find out the truth about him by the way. Be sure to find out the authenticity of the Grenade."

"ok." Diana promised, put the letter paper and Grenade pull ring into the envelope and walked out of the cockpit.

Diane pretended to be careless and walked all the way to the back of the cabin to check the situation of the cabin and ask the passengers what they wanted, just like working. It's almost row 20, and I've seen the one with sunglasses. Diana's heart was pounding involuntarily. She has never encountered such a situation before. She can only keep telling herself not to panic, not to be afraid, and everything will be fine.

Diane went to seat 20d and pretended to take a casual look. She saw the robber with his left hand on his waist and his right hand holding a Grenade on his thigh. Seeing Diane coming, he lifted the hem of his clothes with his left hand, revealing the pistol pinned to his waist, which was obviously intended for Diane to see. Diana pretended not to see anything and returned the envelope according to the instructions in the robber's letter. The robber took the envelope with his left hand, poured out the pull ring in the envelope, carefully put it on the Grenade, and then gently covered the Grenade with the hem of his suit. In the process, the robbers didn't say a word, and Diane didn't say a word, but they already understood.

After returning the letter, Diana turned and walked back down the aisle. She tried her best to stay calm and not let other passengers find anything unusual.

Diana returned to the cockpit and reported what she had seen to Captain Hearn and Owen. After listening to her words, Hearn asked, "Are you sure his Grenade is real?"

Diana nodded and said, "I think it's true. He held it very carefully. I don't think he looks like a mystery. "

Hearn was silent, as if thinking about countermeasures. Owen had no choice but to say, "He should be easy to deal with alone. I sneaked over and caught him, and the danger was lifted! "

Diana looked at Owen with worried eyes and said, "Can you do it alone?" This is too dangerous! "

"I have been a soldier, and it should not be a problem to subdue one or two people." Owen is confident in himself.

Hearn did not comment on Owen's suggestion. He turned to Diana and asked, "Do you know how many people there are?"

"Well, he didn't say this, and I couldn't see it ... but ... but there was a fugitive on the plane, and I don't know if he was with him ..." Diana replied hesitantly.

Hearn sighed and said, "There are so many passengers on the plane that we can't take any chances. We are in the morning and the robbers are in the dark. We don't know how many people they have, how many weapons they have, or what they want to do next. They are all fugitives, and if they are provoked, the consequences will be unimaginable. We can't let any passengers get hurt. It is our duty to put passengers' lives first. You got it? "

"So, we compromise and let them push us around?" Owen doesn't want to be led by robbers like this.

"This is not at their mercy. We will agree to their demands first, and then make plans according to the development of the situation. What do you think? " Hearn has obviously made up his mind.

Owen thought for a moment and nodded helplessly: "It seems that this is the only way."

Next, Hearn picked up the receiver and contacted the air traffic control center, telling the other party that the plane he was driving was hijacked, and then he had to divert to San Francisco according to the instructions of the robbers.

At this time, the plane is flying west about 15 miles north of Aspen, a ski resort in Colorado, at an altitude of 30,000 feet. Captain hearn asked the control center to re-determine the coordinates. After getting the new coordinates, the plane immediately turned around and flew to San Francisco.

Because the robbers were forbidden to warn passengers of hijacking, Hearn had to find an excuse to inform passengers that the plane was diverted. He said into the microphone, "We have received the news that there will be heavy fog when the plane arrives in Los Angeles, so we have to divert to San Francisco. Please understand. "

Hearn's tone was calm, as if nothing had happened. His words soon spread to every corner of the cabin through the loudspeaker, and immediately caused fluctuations among passengers, but the fluctuations soon subsided. It is common to divert to other cities because of the weather. Most people don't doubt this.

Later, Captain Hearn called all the other crew members on the plane together, reported the news that the plane was hijacked, and told everyone to keep a secret, stay calm, not to show any panic and not to make passengers nervous. At the same time, they should stick to their posts and try their best to do their jobs.

Hearn had just arranged all this when the robbers issued new instructions. As before, he asked a passenger in the back row to give Diana an envelope. The robbers seem to remember Diane's face.

Diana took the envelope to the cockpit and handed it to Captain Hearn. Hearn opened the envelope, took out the folded letter paper and unfolded it. I saw a line printed on it: "remove all passengers in the back row and all flight attendants sit in the last row." After reading this letter, be sure to return the original. " Looks like the robbers are already on the move.

Hearn handed Diana the writing paper and said helplessly, "Do as he says."

Diane went to the back of the cabin, returned the envelope to the robber, and then began to transfer the passengers in the back row. Although the robber was sitting in the last row, several passengers in the back saw the Grenade in his hand and realized what had happened. They are all very nervous, waiting for the flight attendant's action. So when Diana arranged for them to sit in the first class, they all stood up happily. Only one person did not move, that is, the fugitive. For the other passengers in the back row, they know nothing about the hijacking of the plane. When Diana arranged for them to sit in the front row, they were all confused. Diana was asked, "What happened?"

Diane had to lie and say, "Oh, nothing. In order to ensure flight safety, we need to redistribute the load. "

After listening to Diane's answer, the suspicious passengers also believed it. Diane doesn't know how much longer she can hide it from the passengers.

After the passengers in the back row moved to the front, the robbers took out their pistols and forced the flight attendants to sit in the last row. At this point, the robbers have completely controlled the Boeing 727. At this time, the plane has entered the landing route to San Francisco airport.