Parks College Parachute Research Group
Modeling the Inflation of Ram-Air Parachutes Reefed with Sliders
J. Potvin, G. Peek and B. Brocato
Published in the Journal of Aircraft volume 38 number 5 page 818-827, 2001
Sliders are aerodynamic devices designed to reduce opening shock by delaying
the canopy spreading stage of parachute inflation. Sliders are used on
almost all ram-air parachutes of 1000 square foot surface area or less and
can be found on an increasing number of round and other cup-shaped canopies.
This paper reports on the continued refinement and validation of an inflation
model of slider-reefed ram-air parachutes proposed a few years ago by one of
the authors. The paper also discusses several model-derived scaling laws on
the dependence of opening shock and inflation time on descent speed,
parachute size, deployment altitude, and other construction and deployment
variables. The model predictions are compared with data collected from a
large number of instrumented jumps performed on manned ram-air parachutes
of various designs and sizes.