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This CONOPS is useful for lower-altitude flights. It is as simple as possible: one event separates two sections of the rocket, and recovery webbing keeps the two pieces connected. A chute is on the cord, which inflates upon being released from the rocket. Typically, the event occurs near apogee because the rocket has no vertical velocity, decreasing the chance for crazy things to happen upon deployment. However, it is not as useful for high altitude flights because the safe speed at which rockets should fall under the parachute is relatively slow. For high-altitude flights, this leaves the rocket prone to drifting for up to several minutes, and possibly several miles.
For most flights under 3000 feet, and most L1 flights, SSSD is fine. We do not need to separate any of the three sections above to design this rocket. For an L1, a 3" diameter tube is commonly used. (2.6" and 4" are also common.) For our example, we add a body tube with an inner diameter (ID) of 3", outer diameter (OD) of 3.14", and a relatively arbitrary length of 15". The basis for a motor section is also a body tube, so we add another one below it. For this rocket, we will also make the nose cone the same diameter as the body tube. It should look like this:
Nose Cone
For a Level 1 rocket, the nose cone is usually empty (or capped on one end).
Dual Separation, Dual Deploy:
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