Pull-Out Pilot Chutes

Q:

 

How do pull-out pilot chutes work, and how do they differ from the standard throw-out system?

A:
Pull-out pilot chutes have been around just as long as the more popular throw-out system; Bill Booth of United Parachute Technologies (then known as The Uninsured Relative Workshop) patented both at the same time in the early 1970s. After that, almost all of the manufacturers began offering a pull-out system on their rigs (most still do), and lots of jumpers chose to use it over a belly- or leg-mounted throw-out system. However, over the years, the pull-out system has declined in popularity. Many of you may not even know that a deployment system other than the bottom-of-container-mounted throw-out pilot chute is available. But the pull-out system has always been there, lurking in the background with a solid core of supporters.

A pull-out deployment system on a United Parachute Technologies Vector show with the main flap open.

On a pull-out system, a jumper packs his pilot chute inside the main container. A short lanyard and handle attach to a straight closing pin that holds the container closed. After the jumper inserts the closing pin, he tucks the lanyard underneath the container flaps to keep it secure and stows the handle at the right corner of the bottom of the container. The pull-out handle has evolved and improved over the years. Initially, the handle (commonly called a “pud”) was not much bigger than the average thumb. Elastic loops sewn to the container held it in place. More recent versions have a larger handle that is held in place by a Velcro tab under a flap at the bottom of the container.

An unpacked pull-out deployment system pilot chute, pin and handle. Photo by Nancy LaRieviere.

To deploy using a pull-out system, a jumper must grab the handle and pull sideways to pull the closing pin, which opens the container flaps. The jumper then pulls the pilot chute into the slipstream and releases it as it inflates. Nancy LaRiviere from Parachute Labs Inc. (aka Jump Shack) provided some insight into the development of the pull-out system on the company’s Racer container: “John Sherman devised the pull-out for the Racer container circa 1974. The logic behind the pull-out design is and was to maintain the proper sequence of deployment and [for the jumper to] not have to rely on the pilot chute to open the container.” As with anything, there are pros and cons to consider. With a pull-out, there is not much of a chance of experiencing a pilot-chute-in-tow malfunction, since the jumper pulls the closing pin to open the container flaps before extracting the pilot chute. So, the container is already open when the pilot chute inflates. It is more efficient to pack, as well, because the jumper can quickly fold and stow the pilot chute and its bridle under the main container flaps. Fans of the pull-out say that during a normal deployment sequence, everything occurs in a natural order: The main container flaps open before the pilot chute inflates and lifts the bag out of the container.

However, the system is not without its challenges. A packer unfamiliar with the system can pretty easily misroute the lanyard and pack a total malfunction that makes it impossible for a jumper to extract the main pin when he pulls on the handle. Total malfunctions due to improperly packed pull-out systems have led to countless reserve rides, as well as several fatalities when jumpers experienced loss of altitude awareness as they struggled to deploy.

A pull-out system on a packed Parachute Labs Inc. racer container with the main flap closed. Photo by Nancy LaRieviere.

Floating handles are another concern with pull-out systems, especially those of earlier design on which the elastic keepers become worn and no longer hold the handle securely. Many jumpers in freefall find floating handles nearly impossible to reach, because sometimes the handles dance around at the end of their lanyards in the burbles above their containers. Others find that dislodged puds will just drop onto their rear ends, where they are easy to locate and pull.

A total malfunction caused by a misrouted lanyard or floating, out-of-reach pud means that main deployment is not an option, and pulling a reserve handle after two failed attempts (altitude permitting) at the main handle is the appropriate response. A pre-jump equipment check can help a jumper spot a packing error and correct it before boarding the plane, but a gear check is only useful if the jumper giving it knows the correct routing for the bridle and lanyard. With so many jumpers and packers unfamiliar with the pull-out system, a rig owner should not rely on others to ensure the rig is closed properly. As with any other skydiving equipment, it is crucial that the user fully understands the operation and correct packing of the pull-out system.

Jumpers also need solid deployment techniques when using pull-outs. Booth remarked, “Pull-outs also require more skill to deploy correctly, because it’s harder to throw the pilot chute out of the burble. This is because with a pull-out, you don’t really have the pilot chute in your hand; you have a handle on one end of a cord connected to it. This means you have to twist your body in a certain way to break up the burble so that you don’t get a pilot-chute hesitation, which is a bad situation because, with a pull-out, your container is already open. This has resulted in a bunch of out-of-sequence deployments and scared a bunch of people.”

Although not as popular as other deployment systems, the pull-out system has stood the test of time, working successfully for nearly 40 years. Some see it as a little quirky, but you can probably say that about everything in skydiving.

—Jim Crouch | D-16979
USPA Director of Safety & Training

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