take the ropes off, put them in the item slots that are empty on the left hand entrance of the hangar door

or just hook them to the extra rope ancors on the floor of the heli pad there are 2 ancors at each rope that way when you land you have them ready to hook up again if needed

Or pick up the rope, scroll the mouse wheel to put it on your back as you swap inventory, scroll back to it, and hit backspace to drop it on the ground.

select the rope, click "backspace" and repeat this process to all ropes.

with ordinary ropes i guess

Alright thanks everyone!
I guess i forgot to mention that i got it long ago, sorry!

where the hell is the eng start buteen