The Orion reentry vehicle will have a parachute system. Like Apollo, they'll have 3:
Orion Parachute Drop Test on May 1, 2013
A model of NASA's Orion spacecraft glides to a successful touchdown during a test of its parachute system on Wednesday, May 1. Orion's three main parachutes, which slow it gradually down for landing, weigh 300 pounds each and can cover almost an entire football field.
Photo and caption source: NASA
They seem so nicely separated in pictures. But from a physics standpoint, the aerodynamic force seems like it should be upward, and that would tend to mush all the chutes together. That would seem quite dangerous, by decreasing the area or making them crumple.
Is there anything about the design of the parachutes and tethers that prevents this? Is there something about the aerodynamics that keeps this from happening? Or is some bumping just not a big deal?