Safe flight-USA Aircraft Group Corporation

Date: 2025/12/29

Civil airliners are not allowed to fly under the following circumstances. These regulations are mainly formulated by the International Civil Aviation Organization (ICAO), civil aviation administrations of various countries (such as the Civil Aviation Administration of China CAAC) and airline safety standards, mainly covering airworthiness, weather, operation management, personnel status and external environment:

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1. Airworthiness problems of aircraft

· Mechanical failure: key systems (such as engine, landing gear, navigation, communication, hydraulic system, etc.) fail or fail to pass the inspection.

· Repair is not completed: regular maintenance is not completed as planned, or it is not approved for airworthiness after repair.

· Inspection is not qualified: safety hazards are found in pre-flying inspection and over-station inspection (such as tire wear exceeding the standard, fuel leakage, etc.).

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2. Bad weather conditions

· Take-off/landing stage:

· Visibility is lower than the minimum operating standard of the airport (such as fog, rainstorm, sandstorm).

· The icing, snow or waterlogging on the runway exceeds the safety standard.

· Strong crosswinds, wind shear, thunderstorms and low-altitude turbulence affect the safety of take-off and landing.

· Route weather:

· Strong thunderstorm areas, severe bumps, volcanic ash clouds (which may damage the engine), strong lines, etc.

· The freezing conditions exceed the de-icing capacity of the aircraft.

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3. Qualifications and status of personnel

· Creet members:

· Pilots are on duty overtime (violation of flight time restrictions).

· The qualifications of the crew members do not match (such as not obtaining the qualification of a specific model or airport certification).

· The pilot's health is not good (such as fatigue, the influence of medication, sudden illness).

· Cabin crew: the number of flight attendants is insufficient or the emergency training is invalid.

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4. Airspace and control restrictions

· Airspace closure: military activities, space launch, airspace control (such as national security reasons).

· Route congestion: Flow control makes it impossible to take off as planned.

· Destination airport closure: due to weather, accidents, facility failure and other reasons.

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5. Operation guarantee issues

· Insufficient fuel: the minimum fuel standard for standby airport and safety reserve is not met.

· Load balance: The loading of goods and passengers does not meet the balance requirements.

· Incomplete documents: missing or incorrect key documents such as flight plans, navigation notices, manifests, etc.

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6. Security threats

· Terrorist attack warning: receive reliable security threats against flights or airports.

· Illegal interference: abnormal behavior of passengers (such as drunken trouble, threatening the crew) needs to be handled on the ground.

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7. Policies and regulations restrictions

· Internal regulations of the airline: additional restrictions for safety risk assessment (such as night flight bans at some airports).

· International sanctions: the ban on the flight of sanctioned countries or aircraft.

· Epidemic control: public health restrictions during special periods (such as flight meltdown during the epidemic).

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8. Passenger-related reasons

· Passengers at safety risk: Passengers refuse to check, carry dangerous goods or sudden diseases affect flight safety.

· Emergency medical incident: There are critically ill patients on the plane before take-off and cannot be properly disposed of.

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Key principle: security redundancy

The civil aviation industry follows the "Minimum Equipment List" (MEL) and the "Safety First" principle, and even minor failures can lead to flight stoppages. The captain has the final decision and can refuse to take off based on safety considerations (the Tokyo Convention and national regulations give the captain absolute safety authority).

For example:

· Volcanic eruption in Iceland in 2010: a large area in Europe was banned from flying to prevent volcanic ash from damaging the engine.

· Thunderstorm weather: Even if the passenger has boarded the plane, the captain may delay take-off because the radar shows a strong thunderstorm on the route.

These strict regulations ensure that civil aviation is one of the safest means of transportation in the world.