Is it permissible for a woman to travel to her husband without a mahram?

Question:
Honorable Shaykh, may Allah grant you success. A questioner says: A man wants his wife to travel to him and come to him in his country, and she comes without a mahram, on the excuse that he is unable to go to her to bring her. Is this permissible?

Answer:
No, this is a sin, due to the saying of the Messenger (peace and blessings be upon him) except with a mahram. Because if she gets sick, who will take care of her? Who will carry her? If the plane makes a mistake or the flight is diverted to another place and she ends up in another country, who will receive her? Where will she go?
A woman needs a mahram. Often the plane changes its route to another country due to an unforeseen circumstance. Where will the woman go? They say her husband will wait for her at the airport. Well, if she goes to that airport, they cannot handle these circumstances. Yes.