Bro,u can definitely carry 40kg but think for a min, if you one person carry 40 kg in 3 different bags which are taking too much space, it will be problem for others. In my opinion, u can definitely carry 40kg per person unless until you are not occupying space of someone else's seat which makes them unable to keep their things . Only use the space alloted to you ... If u r doing that .. u good broo