Have a nice trip.
Why can't you say bon voyage by plane?
When people in China send their friends on a trip, they usually don't forget to say "Bon voyage". Originally, for friends who travel by plane, "bon voyage" is not a word suitable for sending planes. Why do you say that? Let me tell you why.
Aircraft usually choose to fly against the wind when taking off and landing, mainly for two reasons: first, it can shorten the taxiing interval of aircraft taking off and landing; Second, it can obtain very good stability and security. The lift of the wing depends on the relative airspeed between the aircraft and the air, not the relative ground speed between the aircraft and the ground. During the take-off phase, the ground speed of the plane is very small. If you want the plane to fly with satisfactory lift, you need more airspeed. Then, when the ground speed ratio is small, you need the plane to take off against the wind, achieve greater airspeed and take off with lift. It turns out that this is the principle when people fly kites in life. Kites fly high against the wind.
When the plane lands, if it is downwind, the relative speed to the air is small, so the plane must increase its speed to overcome the influence of wind speed in order to maintain normal lift. This not only needs to increase the taxiing distance, but also makes it difficult for the plane to land accurately, and even causes the plane to run off the runway and have an accident. Landing against the wind can avoid this situation and greatly increase the safety.
In addition, the takeoff and landing speed is slow and the stability is poor. If you encounter a crosswind, it will tilt the plane. Therefore, generally speaking, it is possible to land with the wind only if the headwind condition cannot be selected and the runway length is met.
Bon voyage means that the wind is smooth all the way, and the plane can only fly against the wind. If it is downwind, there is only one ending-falling. You wish others "bon voyage", don't you wish others bad luck? So when friends travel by plane, they can use "Bon voyage" instead of "Bon voyage".