Goals:
Develop a reefing parachute that successfully deploys and efficiently controls rocket flight/descent.
Purpose:
Condensing two parachutes (drogue + main) into a singular parachute that can perform the actions of both.
Skirt Reefing:
Suspension-line reefing:
Canopy reefing:
🦑: Not a fan of reefing the suspension lines as it seems there can be issues of it sliding down which could make the parachute expand slowly before the proper time. I would be more interested in looking at skirt reefing primarily and then canopy reefing. Canopy reefing could (negligibly) experience the same issues as suspension line reefing but the effects seem to be minimized by the parachute itself.
Line cutters:
     https://www.apogeerockets.com/Electronics_Payloads/Dual-Deployment
https://www.tinderrocketry.com/the-mako-para-cord-cutter
https://www.tinderrocketry.com/the-piranha-cutter
Line Material:
Open ended, nothing specific is used from what it seems. Obviously needs to be cut-able by the line cutter used.
Lines Diagram:
Assumes separation point is between the MPT and nosecone. Also assumes a skirt-reefing method where the line cutter is attached with lines/avionics wiring to the MPT. The reefing line remains attached to the parachute after the line is cut, so no components should fully separate from the rocket at any point.
Parachute sizing was found using the drag force equation at the bottom left corner of figure 6. Putting in average assumed values resulted into a previously made spreadsheet calculator resulted in a total diameter of roughly 8 feet and a reefed diameter of roughly 3 feet.
Figure 6 Spreadsheet calculator and values used
Using the values in the spreadsheet, the shock force was found on OSCalc as shown in figure 7. For the drogue opening at 30,000ft, the upper bound of force is calculated to be 303.2 slugs*ft/s^2
Figure 7 OSCalc results