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789 bytes added ,  11:26, 27 January 2016
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== Recovery ==
 
== Recovery ==
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So you've launched your rocket and watched it fly upwards as good rockets do. Now you need to bring it back safely. A standard parachute recovery for an L1 rocket involves deploying a single main parachute out of the rocket at apogee.
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[[File:L1_Guide_Delay_Charge.png|thumb|200px|right|Motor delay/ejection charges]]
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So you've launched your rocket and watched it fly upwards as good rockets do. Now you need to bring it back safely. A standard parachute recovery for an L1 rocket involves deploying a single main parachute out of the rocket at apogee. Apogee is the highest point of a rocket trajectory, where the vertical velocity is momentarily zero and the rocket transitions from ascent to descent. This is the point at which the rocket is moving slowest and is ideal for parachute deployment. This is to allow the parachute to properly deploy and minimize aerodynamic forces on it while it deploys.
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For typical L1 rockets, after the motor burns through its main propellant, it burns through a delay grain. This is a slow-burning section at the end of the motor which acts as a timer. Once the delay grain, the flame front ignites the ejection charge, which pressurizes the body tube of the rocket and forces the nose cone out, along with the parachute.
    
== Simulations ==
 
== Simulations ==