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What To Observe : Surface Area & Shape : Canopy Layers : Weight : String : Vents : Frame               
MOVIE 1:   24 seconds
Frame

Since the amount of frontal surface area influences a body's Drag Force when moving through the air, creating a parachute that quickly inflates and remains inflated would be helpful. An external or built-in frame can aid in this. When a non-framed chute deploys, its inflated diameter is only two-thirds the canopy's diameter when it is spread out flat on the ground. Since area is related to the square of the radius (A=Πr2), the chute's area when deployed is less than half than when it is fully spread out. A parachute with a frame thus has the potential to displace nearly twice the volume of air as one with no frame.

There is a trade-off in designing a chute with a frame, however. The weight of the parachute system with a frame will increase. This may be acceptable (when allowed by the rules that govern the model parachute challenge), if sufficiently light-yet-strong materials are used for building the frame.

REALITY CHECK: Parachutes that are packed into a backpack-like container make frame-based parachutes infeasible. Hang gliders, however, do utilize a frame to help the canopy maintain its wing-like shape.

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