Walldiver7
Well-Known Member
- Joined
- Mar 16, 2013
- Messages
- 534
- Reaction score
- 7
Alright, so here's the situation: I was building a scratch design and after (of course) cutting the fins and beveling them, I discover that the motor I based this design had been loaded into OpenRocket incorrectly. The weight of the motor was actually much higher than what was loaded into OR..... and thus, my scratch design was not going to be stable.
So, not wanting to cut new fins, I started looking at what could be done to achieve 1 cal stability. I discovered that if I turned the rocket into a split fin design the cal stability went way up.... To clarify, on OR I cut the fin into two separate fins (typical split fin design) and spaced them only 1/8" apart. My question: Is OpenRocket accurately stated the stability here? It went from a relatively low figure to way above 1 cal. I also found it interesting that the spacing between the fins (1/16 to 1/2 of an inch) didn't seem to make much difference. If OR is correct, then I've saved myself from having to cut a new set of fins!! The downside is... it scrubbed off about 3,000 feet from the apogee with the split fin design.
Can I conclude that the extra drag the split induces is the reason that the stability increased?? Thanks for the help!
So, not wanting to cut new fins, I started looking at what could be done to achieve 1 cal stability. I discovered that if I turned the rocket into a split fin design the cal stability went way up.... To clarify, on OR I cut the fin into two separate fins (typical split fin design) and spaced them only 1/8" apart. My question: Is OpenRocket accurately stated the stability here? It went from a relatively low figure to way above 1 cal. I also found it interesting that the spacing between the fins (1/16 to 1/2 of an inch) didn't seem to make much difference. If OR is correct, then I've saved myself from having to cut a new set of fins!! The downside is... it scrubbed off about 3,000 feet from the apogee with the split fin design.
Can I conclude that the extra drag the split induces is the reason that the stability increased?? Thanks for the help!
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