Looking at (non-mahram) women is haram because Allah has commanded the believers to lower their gaze. Looking at women does not break your fast, but you have to lower your gaze.

If the plane takes off before sunset, and you want to complete that day’s fast, then you should not break your fast until the sun sets in the place where you are in the air.

1- It is haram for a man to touch, hug, or kiss a girl who is not his mahram whether he is fasting or not. 2- If semen (maniy) is emitted because touching, hugging or kissing a non-mahram girl, then the fast is invalidated and one must make up that day. If no semen was emitted, then the fast is still valid.

If a fasting person eats or drinks in Ramadan or a voluntary fast out of forgetfulness, then his fast is complete and he does not have to make it up.

If a person starts fasting in one country and travels to another where Ramadan began later, they must continue fasting until the local community observes `Eid. This may result in fasting 31 days. However, if they move to a country where Ramadan ends earlier, they should break the fast with the locals and make up missed days later.