BRS-6 General Installation Guide - CAFE Foundation

With a few minor exceptions, all of the textile components in our parachute systems are
fabricated from either Kevlar® or Nylon. The materials used in BRS parachutes, including the
fabric, reinforcement tapes, suspension lines, and threads, are all woven to military or industry
specifications that define specific parameters such as raw fiber materials, yarn count, yarn
twist, weave type, and finish.
Parachute material strength requirements are ultimately based on deployment characteristics,
or specifically, deployment loads. A typical deployment load profile begins with a snatch force
which occurs when the parachute assembly is initially extracted from its container and pulled
to full line stretch. This is usually not felt by the pilot/passenger. When air begins to fill the
canopy, higher inflation loads result. The number and magnitude of the peak loads is
dependent on airspeed at deployment, payload weight, and atmospheric conditions.
2. The Slider
After the parachute is completely extracted and exposed to the relative wind, it begins to
inflate, generating drag forces to decelerate the airplane. The magnitude of these drag forces,
or inflation loads, for a particular parachute design is a function of the airplane's weight, the
airspeed at deployment, and the rate of inflation.
The inflation rate of BRS parachutes is controlled by a proprietary slider, an annular shaped
fabric panel with metal grommets along its perimeter. The parachute suspension lines are
routed through the grommets such that the slider is free to move along the suspension lines.
The parachute is packed with the slider positioned at the top of the suspension lines. Since the
diameter of the slider is significantly less than the open diameter of the canopy, it limits the
initial open diameter of the parachute and its rate of inflation as shown in Fig. 2. Once the
dynamic pressure acting on the system decreases to a safe level, the slider moves down the
lines, allowing the parachute to inflate to its full diameter.
Maximum Reefed Disreefing Full Canopy Deployment
Condition Condition
Figure 2.
BRS Annular Slider
Sliders can be "tuned" for a particular set of deployment conditions by adjusting their
geometry. For example, increasing the size of the slider's vent will increase the airflow into the
parachute and therefore increase the initial rate of inflation. Decreasing the fabric area will
decrease the drag on the slider and allow it to disreef at a higher dynamic pressure, thereby
increasing the final rate of inflation.
BRS-6 General Installation Guide (Models 600 through 1800) Page 9 of 47
BRS Document № 020001-03 Revision D Copyright © 2008, BRS Inc.