PARACHUTE RIGGER HANDBOOK
 

Chapter 2

PILOT CHUTES

A pilot chute is a small parachute, which is used to deploy the main or reserve parachute. In the earliest uses of parachutes, the parachute was static line deployed. With the advent of manually operated or “free fall” parachutes, the need for a pilot chute was quickly recognized.

There are two basic types of pilot chutes. The first is the spring-loaded design. This uses a collapsible spring, which is compressed in the parachute container and held closed with the ripcord. When the ripcord is pulled, the pack opens and the pilot chute launches into the airstream. The pilot chute provides drag and pulls the canopy from the pack as the parachutist or load falls away. During this process, the pilot chute also provides tension on the lines of the deploying canopy and helps the opening sequence. Spring-loaded pilot chutes are used primarily for emergency and reserve parachutes. In addition, they are used in military free fall and training systems for the main parachute.

The second type of pilot chute is the “hand deploy” design. This type consists of the pilot chute canopy but does not have a spring to launch it. Instead, the parachutist extracts the folded pilot chute from a pouch or the container and launches it into the airstream. The pack is held closed by a locking pin attached to the bridle of the pilot chute. As the pilot chute inflates, it extracts the pin from the locking loop and pulls the parachute from the pack. The rest of the opening process is similar to the spring-loaded pilot chute. This configuration came into popularity in the mid 1970s and is now the primary method of deployment in skydiving.

SPRING-LOADED PILOT CHUTES

Spring-loaded pilot chutes date from the 1920s. However, it wasn’t until 1940 that the spiral vane pilot chute was invented. This design used a spiral spring that is easy to collapse and pack. The most common type of spiral vane pilot chute used today is the MA-1 model. [Figure 2-38] This is used in several military parachute assemblies. In the early days of skydiving, military pilot chutes such as the MA-1 and others were popular. Soon commercial designs were introduced that improved on the MA-1 with better launch and drag characteristics. These included the Grabber® and Hot Dog® pilot chutes. Both of these were primarily for use with main parachutes.

With the advent of the hand deploy pilot chute for the main, most of the improvement in spring-loaded pilot chute design has focused on its use in the reserve or emergency parachutes. This has paralleled the improvements in container design and the increased use of AADs. Both of these require better pilot chutes than in the past.

One example for reserve use is the Magnum® pilot chute designed by National Parachute Industries. [Figure 2-39] With its unique shape, it provides maximum drag at low speeds such as are experienced during cutaways. Its design has been licensed by other manufacturers for use in their assemblies. Additional designs include the Vector II reserve pilot chute and the Stealth pilot chute. The Vector II design is a “ballute” configuration that eliminates the use of mesh. In the event of an unstable launch on its side, the mass of fabric is sufficient to lift the pilot chute and deploy the parachute. The Stealth pilot chute uses a conventional mesh design but has a unique spring/cap configuration that allows the pilot chute to virtually disappear when packed, hence the name.

 
 
 
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