Thunderstorms occur frequently in summer. How to ensure flight safety?

Have you ever had the experience of being woken up by a thunderstorm after falling asleep late at night?

Civil aircraft that stray into thunderstorm areas are easily affected by a series of severe weather conditions, such as lightning strikes, heavy rain, strong winds, and ice accumulation, which are extremely harmful. Therefore, it is of great significance to study and analyze thunderstorm weather and its impact on aviation safety.

Causes and characteristics of thunderstorms

Humans have always been in awe of the power of thunder and lightning. Ancient Chinese people had many simple understandings of thunder and lightning from a mythological perspective, believing that they were created by "Thunder God and Lightning Mother". In Western legends, there is also the image of "Thor" holding a giant hammer to strike out thunder and lightning.

It was not until the famous Franklin kite experiment in the mid-18th century that humans realized that lightning is a discharge phenomenon in the atmosphere. In fact, lightning is bred in the atmosphere by thunderstorms, and it is also accompanied by dense dark clouds and heavy rain.

Thunderstorms are mainly caused by cumulonimbus clouds with strong airflows and are the product of the violent movement of cumulonimbus clouds. Lightning and thunder often occur, so they are called thunderstorms.

Thunderstorms require three key factors: a large amount of uncertain energy, abundant water vapor and strong impact. Thunderstorms in my country mainly occur in summer, with a much higher frequency in the south than in the north, and more in mountains than in plains.

Impact of thunderstorms on flight safety

Thunderstorms bring a series of weather phenomena such as strong winds, lightning, heavy rain, hail, low visibility and low temperature. Therefore, when an aircraft flies in a thunderstorm, in addition to being hindered by flying in the clouds, it will also encounter a series of other problems.

Turbulence. Turbulence is mainly caused by strong winds and strong vertical air currents that accompany thunderstorms. Vertical air currents include air currents that move in both ascending and descending directions, and their strengths vary. When an aircraft is affected by vertical air currents, it will not only make it more difficult to control the aircraft and damage the aircraft structure, but more seriously, it will cause the aircraft to lose control and endanger safety.

Ice accumulation. Thunderstorms bring rainfall and cooling. When an aircraft flies in thunderstorm weather, the surface of the fuselage will be covered with condensed water droplets, which are easy to freeze in a low-temperature environment, increasing the load on the fuselage, making it difficult for the aircraft to fly normally, and seriously threatening flight safety.

Heavy rain. Heavy rain is the most typical phenomenon of thunderstorm weather. When an aircraft flies in heavy rain, rain enters the constantly rotating compressor, increasing the thrust of the engine, which speeds up the aircraft to a certain extent. However, if the intensity of the heavy rain is too strong, it will cause the engine to stall.

Hail. When there is thunderstorm weather, if the aircraft is flying at an altitude below 8,000 meters, it is more likely to encounter hail; if it is flying at an altitude above 10,000 meters, it is less likely to encounter hail. Hail is different from rainstorms. It has mass and volume. If the aircraft is hit by hail, it will cause serious damage to the fuselage.

Lightning. Thunderstorms are usually accompanied by lightning. If an aircraft flies in a thunderstorm area, it is very likely to be electrocuted. The impact of lightning on aircraft includes two aspects: First, the impact of lightning itself on the aircraft. There are positive and negative charges in cumulonimbus clouds. Once the positive and negative charges reach the specified value, discharge phenomena will occur inside, outside and at the bottom of the cumulonimbus clouds. If the aircraft is electrocuted, the fuselage and various equipment inside the aircraft may be damaged to varying degrees. Second, the instantaneous electromagnetic field generated by lightning and lightning strikes will interfere with the aircraft's communication system and instrument panel data, increasing flight safety risks.

Safe flight measures

Strengthen thunderstorm warning. Thunderstorms pose a serious threat to flight safety. Civil aviation meteorological personnel should carefully analyze meteorological data, issue thunderstorm warning information in advance, and pass it on to relevant departments as soon as possible. If there is a severe thunderstorm, all flights during this period should be canceled or the take-off time should be postponed. Meteorological personnel should comprehensively analyze meteorological data, improve the level of thunderstorm warning and forecasting, strengthen communication with aviation departments, and ensure timely delivery of meteorological information.

Responses at different stages of flight. Before the flight, pilots should take precautions against the possible impact of thunderstorms; if thunderstorms occur during takeoff, pilots should turn on the weather radar, carefully observe the weather conditions, and avoid the thunderstorm area in advance; if thunderstorms occur during flight, it is very easy to be struck by lightning, so pilots should remain calm and respond well to ensure the safety of passengers' lives and property.

Thunderstorms are caused by complex factors, with diverse movement paths, many aspects involved, and can last for a long or short time. The prediction accuracy needs to be improved. They are hidden, sudden, instantaneous, diverse, and systematic, which brings a series of challenges to the safe operation and control of flights. All civil aviation departments should pay attention to the impact of thunderstorms on civil aviation operations, keep the "three fears" in mind and on their shoulders, do a good job in preventing and responding to thunderstorms, improve the quality of crew members, improve management systems, and focus on professional skills to effectively reduce the losses caused by thunderstorms and ensure the safe operation of civil aviation.