Figure 4-33.  Pull pilot chute kill line from bottom of bag.  Figure 4-35.  Drop the excess line into the pilotchute. Figure 4-34.  Pull the kill line through the bridle. 4-8 Main canopies have changed dramatically over the last  several years and, consequently, different opening problems  have emerged. Some canopies are inherently hard openers,  while others are inherently slow openers. Accuracy canopies,  with their thick airfoils and large overhanging topskins, fall  into the first category, while thinner airfoils, with flatter trim  and baffled leading edges, tend to fall into the latter. One of the most common problems encountered is that of  hard openings.  Line strip or line dump is the leading cause of  hard openings. This occurs when inadequately-stowed lines  come off of the bag all at once instead of releasing one line  bight at a time in an orderly fashion, and subsequently the  canopy is allowed to inflate prior to line stretch resulting in  sometimes an explosive opening. Securing the lines so that it  takes approximately 12 pounds of force to release each bight  is accomplished with a proper stow band and balancing the  weight and mass of the lines by placing 50 percent of the  line weight and mass on the mid-section of the bag and 25  percent of the weight and mass on each side of the bag. This  alleviates the problem of line strip.  Deployment and Inflation Characteristics