Google silver parachute ask Allen. He wrote an article regarding ram vs round emergency chutes. Very informative.

On Monday, June 22, 2015 at 9:59:25 AM UTC-7, Dan Marotta wrote:
Recently somebody made a comment about my emergency ram air
parachute and whether or not it has a slider to to slow deployment.*
I checked with my rigger and jump instructor and here's what he
said:



Your parachute has a slider. The maximum airspeed for slider-off deployments is 65 mph. In an aircraft emergency, you will almost always be deploying at a higher speed than that, so the slider is absolutely necessary. Deploying slider-off at high speed can damage the gear and maybe the jumper.. Your parachute is designed to open as fast as possible without causing damage. It should take about 3 seconds/300 feet for it to open in most situations. Exactly the same as a round parachute of roughly equivalent area.



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Dan Marotta