Industry Response to the Bridle-Piercing Issue

Over the past several years, USPA has received reports of at least six jumpers who experienced locked main containers after their main closing pins pierced their pilot-chute bridles when they attempted to deploy. Thankfully, all of the jumpers were able to successfully deploy their reserve canopies past their main pilot chutes and land uneventfully.

Some manufacturers suggest an alternate routing method—bringing the bridle up to the pin from the bottom of the container flaps—to prevent the pin from piercing the webbing. Full instructions for United Parachute Technologies’ method can be found at tinyurl.com/btal9rz.

Since the problem first came to light, the manufacturers have addressed the issue in various ways. Aerodyne Research started adding Kevlar reinforcement between the two layers of tape near the pin area of the bridle. United Parachute Technologies offered an alternate routing method for the bridle on its sport containers. This method involves routing the bridle from the bottom of the container flaps, which makes it nearly impossible for the pin to pierce the bridle during deployment. This is essentially the same method that Parachute Laboratories Inc. (Jump Shack) has always used for routing the bridle on its Racer container. Some manufacturers have addressed the issue by suggesting various pin orientations—from “smiling” to “frowning” and everything in between—while maintaining their instructions to route the bridle from the top flap past the closing loop toward the bottom of the container.

USPA first learned of the bridle-piercing malfunction in 2009, and Parachutist published an article about it in November 2009, followed by another article in November 2010 (after jumpers reported two more instances following the earlier article). Both articles provided the manufacturers’ packing tips to help jumpers avoid the problem. However, since the publication of the articles, several riggers have contacted USPA with concerns that there’s more to the issue than just bridle routing and pin orientation. These riggers stated that bridle material and design were most likely to blame for the phenomenon. Most bridles consist of two layers of type-III ribbon-weave-nylon tape rated for a tensile strength of 525 pounds. Some of the riggers suggested that manufacturers replace this bridle material with type-IV square-weave-nylon tape, which has a much stronger tensile strength of 1,000 pounds. Some suggested using Kevlar as reinforcement between the layers of type III (although others questioned the effectiveness of the solution, suggesting that the pin could still slide through one layer and lodge there).

So, USPA contacted the Parachute Industry Association to ask it to place the subject on its August 2012 meeting agenda. According to the meeting minutes, the PIA Rigging Committee discussed the issue but did not come away with any suggested changes for the design or material used for bridle manufacturing. The committee discussed the issue with the manufacturers’ representatives who were present, and all seemed to think it was a packing issue. Here is an excerpt from the PIA meeting minutes:

 

“Pin-bridle piercing: One manufacturer suggested that the problem was most likely to occur when the exposed portion of a kill-line bridle was scrunched or collapsed slightly between the closing pin and the top of the deployment bag. Possible causes for the scrunching or collapsing would include:

  • Pilot chute not cocked completely because of poor packing technique
  • Pilot chute not cocked completely because of kill-line shrinkage
  • Positioning of the window on the bridle requiring moving the bridle to check the kill-line color indicator

Some possible solutions:

Changing the routing of the bridle so that it runs from the deployment bag out the bottom of the side flap instead of the top of the side flap. One manufacturer (Jump Shack) has always done it this way, and one manufacturer (UPT) has recently changed their packing instructions to include this method. However, other manufacturers present believed that when maintained and packed according to their instructions, bridle routing was not an issue.

Orientation of the closing pin. When the pin is packed in a ‘frown’ orientation, rotation of the pin is away from the point. This is the orientation required by Mirage Systems.

No manufacturer thought that adding reinforcing (Type III, Type IV, Kevlar tape, etc.) would help, as the pin has to pierce only one layer to lock the bridle. Kevlar in particular is problematic, since the weave loosens once it has been in service even for a short while.”

 

So, where does this leave the jumper who is concerned about this type of malfunction? Like everything else in skydiving, opinions vary depending on whom you talk to. Although some jumpers and riggers are convinced that using different bridle materials would solve the problem, most of the manufacturers seem to think that the standard packing method works as long as the bridle is routed and packed properly. Others feel that using an alternate method of bridle routing, from the bottom of the flaps, is the answer. With all the uncertainty, it is probably best to speak with the manufacturer of your particular container. But perhaps most importantly, you need to realize that this type of malfunction exists and, although there are several possible ways to avoid it, you need to be prepared to take action if you are ever faced with a locked container and a trailing pilot chute. (The USPA Skydiver’s Information Manual Section 5-1 E discusses the pilot-chute-in-tow malfunction.) So far, in each instance, the outcome has been a successful reserve deployment, but it’s always best to avoid a malfunction in the first place.

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