MCriscione
Well-Known Member
- Joined
- Jul 9, 2015
- Messages
- 302
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So about three months ago, I started to look around for something exciting I could do with my daughter on weekends this summer. I can't recall what it was that made me start searching for nearby model rocket clubs, as I hadn't built/launched one since I was in elementary school. Regardless, I found CMASS launches practically down the street in Acton and quickly started building.
Fast forward...
So after building some kits, I quickly ventured into scratch building. After a couple 3-4FNC's I started looking at my options for variety. The ducted rockets looked interesting, and so did rear ejection. So I started searching. I found the plans for an old (1970) Estes "Design of the Month", the Black Knight (www.plans.rocketshoppe.com/mrn/designs/Black_Knight.pdf)
The concept of a dual chute rocket, rear ejection rocket appealed, and the ducted ejection hit was there too. Perfect. But, I don't want to just copy somebody's plan. So I threw the plan out the window and just kept the concept of dual, ducted, rear ejection. From there, I got concerned. Two parachutes from separate locations, but right next to each other? Seemed like a formula for tangled lines and plummeting rockets. Better move them further apart rather than having them right next to the main BT. Parachutes in pods then. OK. I'd seen that most of the ducted ejection designs used body tubes to redirect the ejection gasses. Running body tubes, even BT-5 outwards from the main BT and into the airstream seemed like it add a huge drag factor. Alright then, pods usually go out on the ends of fins, lets leave them there and just put the tubes into the fins. Easy. Eventually, threw together a design in Solidworks just to get an idea of proportion, shape, etc. but the majority of the project came together a bit less orderly.
Disclaimer: I have no idea if anything like this has been done before. I did a bunch of searches here and around the web for construction like this and didn't find much of anything. If there is any resemblance to some other project / kit, it was unintentional and completely without my knowledge. However, if there was, I'd really like to hear about it, so please let me know if this reminds you of anything! Onwards to pictures!
Fast forward...
So after building some kits, I quickly ventured into scratch building. After a couple 3-4FNC's I started looking at my options for variety. The ducted rockets looked interesting, and so did rear ejection. So I started searching. I found the plans for an old (1970) Estes "Design of the Month", the Black Knight (www.plans.rocketshoppe.com/mrn/designs/Black_Knight.pdf)
The concept of a dual chute rocket, rear ejection rocket appealed, and the ducted ejection hit was there too. Perfect. But, I don't want to just copy somebody's plan. So I threw the plan out the window and just kept the concept of dual, ducted, rear ejection. From there, I got concerned. Two parachutes from separate locations, but right next to each other? Seemed like a formula for tangled lines and plummeting rockets. Better move them further apart rather than having them right next to the main BT. Parachutes in pods then. OK. I'd seen that most of the ducted ejection designs used body tubes to redirect the ejection gasses. Running body tubes, even BT-5 outwards from the main BT and into the airstream seemed like it add a huge drag factor. Alright then, pods usually go out on the ends of fins, lets leave them there and just put the tubes into the fins. Easy. Eventually, threw together a design in Solidworks just to get an idea of proportion, shape, etc. but the majority of the project came together a bit less orderly.
Disclaimer: I have no idea if anything like this has been done before. I did a bunch of searches here and around the web for construction like this and didn't find much of anything. If there is any resemblance to some other project / kit, it was unintentional and completely without my knowledge. However, if there was, I'd really like to hear about it, so please let me know if this reminds you of anything! Onwards to pictures!
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