The accident rate of many casualties caused by major aircraft accidents is about one in three million. Aviation is the safest long-distance transportation mode, and it is getting safer and safer. Thirty years ago, the incidence of major accidents was once every1.400 million miles. Today, there are still 654.38+04 billion miles away from major accidents, and the safety has been improved tenfold.
Why do civil airliners need to land manually? Why can't all countries allow blind landing on the runway with CAT3 in poor visibility, and the corresponding airports must have blind landing equipment with sufficient accuracy? China does not allow automatic landing. Use CAT2 at most, and the autopilot must be disconnected before landing. However, the comfort of automatic landing is not high.
Why do civil airliners smoke? This is the so-called wake.
Only when the jet plane flies in the gas layer below -20℃, the air humidity is close to or saturated, and the atmosphere is relatively stable, can the wake cloud be generated. Generally speaking, at the altitude of 10000 m to 7000 m, aircraft are prone to form wake clouds. Beyond this range, the aircraft will not produce the phenomenon of "smoke".
According to relevant data, at present, the temperature of aircraft tail outflow is mostly -4 1℃ ~-60℃, accounting for about 86% of aircraft wake. If the temperature is higher than -40℃ or lower than -60℃, the aircraft wake rarely appears.
Think about it, when you are sitting in an airplane, the temperature outside is -4 1℃ ~-60℃. Is it terrible?
Why civil airliners need to land manually instead of relying entirely on automatic landing still has its limitations. Moreover, it is not reliable to give your life to a program that God knows whether it is flawed or not.
Are fighter planes safer than civil airliners? 1. It is more difficult to fly a civil airliner than a fighter. Fighter pilots can't parachute away, civil aviation pilots can't, and there are hundreds of holes in the back. Fighter pilots are soldiers, and the duty of soldiers is to defend the country, not to make money. Civil aviation pilots earn money and do not need to defend their country. I don't know who has a higher salary than civil aviation, but as we all know, the salary of fighter pilots is definitely several grades higher than that of civil aviation. Fighter pilots are trained by the state, and they eat and drink, while civil aviation pilots come out of universities at their own expense (my classmate is in civil aviation university of china now, so you have to pay). Even from this point of view, it seems understandable to give more wages to civil aviation.
The safety factor should be high, after all, they are all professionally trained, and soldiers can eject to save their lives when they are in danger.
Why do civil airliners fly so high? There are such aircraft, such as ground effect aircraft and hovercraft. There are many reasons why planes fly high.
1, near the ground is called the troposphere, which is very unstable to fly, but the troposphere is much better.
2, the near-earth flight resistance is great, the fuel consumption is high, and it is not cost-effective.
It is very dangerous to fly at high speed near the ground.
Why are all civil airliners with a single vertical tail, which can meet the needs of fuselage deflection? Besides, in general, ailerons are used for turning, and only one tail rudder is used when crosswind is played. Besides, there is no place for the passenger plane to install two vertical tails.
Why doesn't a civil airliner have a parachute? Some netizens questioned why passenger planes are not equipped with parachutes, which can increase the chances of passengers surviving. Actually this is a misunderstanding. First of all, it needs to be clear that a civil airliner equipped with a parachute will not increase the chances of passengers surviving. On the contrary, it may also lead to a decrease in passenger survival rate. The survival rate here refers to the survival considerations of all flight accidents. After all, apart from a few air crashes, there are still many aviation accidents, and passengers can survive safely.
1, skydiving requires professional knowledge
Even professional parachutists or paratroopers, skydiving is not 100% safe, and skydiving must undergo special training. Most of the passengers of civil airliners do not have professional parachuting skills, and there is a great overload in the few seconds when they open their parachutes. Moreover, if the parachute bag is opened at the wrong time, passengers will die because of the high speed of hitting the ground, and the chance of survival is very low.
2. The parachuting environment is unfavorable
First of all, most civil airliners fly at 7000-12000m, far exceeding the normal skydiving altitude (500-1500m). Even if you can open the hatch and skydive, passengers will face high altitude hypoxia, cold and high-speed airflow, and the probability of death is far greater than the survival rate.
Secondly, civil airliners basically use compression chamber, which means that if the hatch is opened at high altitude, passengers will fly out with the airflow like shells because of air pressure (see Hollywood blockbusters for details). High-altitude pressurized skydiving requires a complete set of ejection devices, which is unrealistic in civil aircraft.
Finally, most civil airliners adopt the layout that the lower wing is dihedral and the engine is installed under the big wing, so passengers are easily sucked into the engine and ground into paste when parachuting.
3. Most passenger plane crashes are in the take-off and landing phases.
Accidents of civil aviation aircraft mainly occur in "taxi-take-off" and "approach-landing" sections, accounting for more than 80% of the total accidents, and more than 50% of the accidents are caused by low altitude, ultra-low altitude and the ground. At this time, the aircraft has low altitude and slow speed, and the lift-to-weight ratio is in a subcritical state. In the event of an accident, the plane has little room for maneuver, which directly affects the two key factors of skydiving success: altitude and time. Without height, even if the professional skydiving team comes, it is a free fall; There is no time, no jumping, just free fall.
In addition, according to the history of world civil aviation, the probability of civil aviation accidents is extremely low. According to ICAO data, the overall accident rate of global scheduled commercial flights in 20 13 years was 2.8/1 1,000,000.
4. What are the considerations of passenger aircraft's load capacity and economy?
Installing parachutes and ejection devices on civil airliners will inevitably greatly increase passengers' load and reduce their mobility. Therefore, civil airliners need to reduce seats to keep the passenger capacity stable, and the ticket revenue will be reduced.
Secondly, the income from installing ejection devices is too low. Military combat opportunities are equipped with ejection devices, because the value of fighter pilots is high, so the potential benefits of ejection escape systems on each aircraft are also high; However, there are very few opportunities for civil aviation aircraft to escape by ejection, and the value of air tickets purchased by passengers is far from meeting the manufacturing cost and fuel consumption of each ejection system, which is a great burden for civil aviation companies.
Although there is technology to equip the whole passenger plane with large parachutes, it is still difficult to assemble. One of the important reasons is that the parachute is too heavy, which means that most of the payload of the passenger plane will be lost, reducing the number of passengers and reducing the economic benefits. This kind of system is very complicated and bulky, and various safety devices are needed to prevent it from being unfolded. And if the plane stalls at high altitude, I'm afraid there is not enough time to open the parachute.
5. Moral considerations
If a civil airliner with a landing gear crashes, who will be the first to parachute?
The passenger plane is not equipped with a parachute, which objectively ensures that the crew will do their best to save the plane and passengers. As a pilot's professional ethics, the only goal after flying is to make the plane land safely. Even in the event of an accident, the survival rate of an emergency landing of a passenger plane is much higher than that of a passenger skydiving. Besides, when the passenger plane crashed, there was not enough time for all passengers to skydive. When the opinions of the crew conflict with those of the parachuting passengers, it is particularly important to keep the passenger plane stable and obey the command of professionals (in most cases, the crew).
Why doesn't a civil airliner have a parachute? Suppose the air crash happened at high altitude. Passengers scrambling to parachute to escape will destroy the balance of the plane, which is not conducive to the pilot's control of the plane and may cause even greater disasters. In addition, skydiving is a technical activity, and people without professional training may die or be disabled if they jump. In the low temperature, hypoxia and low pressure environment at high altitude, human beings can't survive without protective equipment. If the plane has an accident during take-off and landing, people will have no chance to skydive. Therefore, it is useless to install parachutes on civil aircraft.