Travel Days are not for Real Work

I am useless on airplanes to airports. Before a trip I tell myself, “bring a book”, “work on this project on your computer” etc. But as soon as I get to the airport or plane my energy is depleted, gone. It doesnt matter if I have lounge access, or if I’m sitting in business class with a little extra leg room, I have no energy for deep/real work. And I have had to accept that regardless of what I think before hand, those travel days are “dead days”.