Flying Y-wing Model Rocket

grabcad

This is a flyable Y-wing model rocket. When I designed this model I tried to duct the ejection charge into engine pods, eliminating the need for recovery wadding. After flight testing, I found the ducts do not cool the ejection charge enough. I suggest wrapping your chutes in recovery wadding or pushing some wadding into the ducts before each flight. The model also features a small payload bay if you do not glue the PNC50-AC in place.The RockSim file recommends a D12-5 motor. Flight tests show that this model arcs more than RockSim expects (possibly due to the launch lug being far from the centerline of the model). A D12-3 motor is a better choice. To complete the model you also need my 18mm Rocket Engine Retainers for Model Rockets files (specifically the Jet Engine Retainer and the BT55 Threads), my 24mm Rocket Engine Retainers for Model Rockets files (specifically the Retainer Ring), my PNC55-HS files and my PNC50-AC files. BT55 tube (at least 170mm long), BT50 tube (at least 60 mm long), BT5 tube (at least 50mm long), 2 400mm plastic parachutes, 2 straws 210mm long (used as launch lugs for a 3/16in rod), and 2x 1100mm of mid-power shock cord are also required. If you wish, you can decorate the BT50 with small dowels or other parts for a more mechanical look.The included SolidWorks Assembly (.SLDASM) file and RockSim (.RKT) files can be used to assemble the model.Kit with instructions available on Etsy:https://www.etsy.com/listing/973789330/flying-y-wing-model-rocketI have currently flown this model 4 times: Flight 1: D12-5, Nice stable flight and full deployment of both chutes. On landing one engine pod snapped off and I found one chute was singed slightly. I enlarged the chute size in this version to reduce the chance of a repeat failure.Flight 2: D12-5, great boost phase, but the delay was too long this time. Deployment happened a few seconds after apogee. The shroud lines ripped off one chute and the model crashed and broke. When I recovered the chutes I found they were a little burned.Flight 3: D12-3, model arced smoothly with ejection slightly after Apogee. On this flight, I was testing more chute protection methods to supplement the ducting. One chute was protected by fireproof insulation "dog barf" pushed into the duct tube. the other was wrapped in recovery wadding. Wrapping the chute in wadding was more effective. One of the shock cords burned and broke, causing the model to land too hard and break.Flight 4: D12-3, great flight with successful deployment of both parachutes. During decent, the chutes tangled but still created enough drag to slow the model. One strut broke, but this was a spot it had broken before and was weaker there.