I can certainly understand your concern.
He really needs to see a doctor or go to an ER asap before he flies again.
Coughing up blood could be caused by:
plus other things.
He needs to have test such as a
It is possible that he has a bleeding ulcer too that could caused him to spit up blood.
The hair off his legs is indicative of decreased circulation but can also be caused by his pant leg rubbing it off.
I am very concerned for your husband too since he is having swelling with the coughing up blood as it could indicate his lungs filling up with fluid.
Please urge your husband to be seen ASAP.
I know this is scary but he is young and should bounce back quickly.
Best wishes to you and your husband.