Changes

[[File:L1_Guide_Delay_Charge.png|thumb|165px|right|Motor delay charge]]

[[File:L1_Guide_Delay_Charge.png|thumb|165px|right|Motor delay charge]]

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.

Recovery is the second stage of a simple non-complex rocket, aka basic L1. Although it would seem like the largest percentage of failure would happen during ascent, 75% of failed rockets are a result of a faulty recovery system. Common points of failure for an L1 are: the parachute did not deploy out of the airframe, the parachute deployed too soon before or too far after apogee, line tangling, and too quick of a descent. All of these aspects are things that you should consider when compiling your recovery system.

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. To test whether your nose cone has the proper fit (tight enough to stay on during flight but loose enough to eject for recovery), hold the back end of your completed, unloaded rocket to your mouth and blow hard with a good seal. The nose cone and parachute should both pop out.

 

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 it has burned through the delay grain, the flame front ignites an ejection charge loaded in the charge well at the front of the motor. This ejection charge, typically black powder, pressurizes the body tube of the rocket and forces the nose cone out, along with the parachute. To test whether your nose cone has the proper fit (tight enough to stay on during flight but loose enough to eject for recovery), hold the back end of your completed, and unloaded, rocket to your mouth and blow hard with a good seal. The nose cone and parachute should both pop out. If you are incapable of doing this, another test can be done by vigorously shaking the rocket by holding the nosecone. The nosecone should separate from the rocket by doing this.

== Simulations ==

== Simulations ==