This simple fix works 100%. Necessary materials:
1 18" slide-out tubular curtain rod
Length of split black foam pipe insulation (smallest diameter)
Fit curtain rod into place about 1/2" above the clothes rod. Cut length of foam tube and slip on to curtain rod. Adjust distance from permanent rod according to type of hangers you use.
Set it onto tops of hangers while on the road. When you get to your destination move it easily up so you can use your closet normally.