A large Boeing international flight, such as Boeing 777-200, can carry fuel for at least 12 hours or more, and more, can fly for 24 to 30 hours.

At the time of September 11, Gemini Summer was not crashed by an airplane, but because the airplane was full of fuel, which ignited the whole building after the explosion, until the temperature reached the melting point of reinforcing steel bars and the reinforcing steel bars were melted down, which resulted in tens of floors above losing their supporting force, collapsed instantaneously and crushed dozens of floors below together.

In addition, searching for an airplane is really more difficult than anything else....