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So I’ve been mind simming a mach/mile project for a while now and just started an Open Rocket sim to validate some of my ideas, and came to a realization that I don’t know how to use some of the flight sim data that it provides to me.
Specifically, the whole correlation between Max Velocity and Max Acceleration (if there is one). I even went back into some of my other sims of rockets that I’ve built and I’m only now becoming aware of the fact that, while certain motors may be aerodynamically stable due to the CP/CG relationship, I may be WAY underbuilt for the acceleration loads that certain Vmax and others may provide! :jaw:
I’m taking it that Max Velocity is the highest predicted speed, which I’m shooting for something over mach-ish. oint:
It’s Max Acceleration where I get fuzzy. What is this actually telling me? Can I correlate this to how many G’s the vehicle can expect to endure? As in “a real kick in the pants” vs “slow, steady push”?
Also, isn’t material strength going to interact with the Max Acceleration figures? I’ve seen a few flight failures where the airframe tubes crumpled at the mach transition (and I understand that), and a few that failed way earlier than that (presumably from too many G’s?).
How do you guys approach analyzing if your airframe is capable of ‘taking the hit’ from a certain motor? Sim? Gut check? Seat of the pants? Hope for the best?
Or am I over analyzing it?
Specifically, the whole correlation between Max Velocity and Max Acceleration (if there is one). I even went back into some of my other sims of rockets that I’ve built and I’m only now becoming aware of the fact that, while certain motors may be aerodynamically stable due to the CP/CG relationship, I may be WAY underbuilt for the acceleration loads that certain Vmax and others may provide! :jaw:
I’m taking it that Max Velocity is the highest predicted speed, which I’m shooting for something over mach-ish. oint:
It’s Max Acceleration where I get fuzzy. What is this actually telling me? Can I correlate this to how many G’s the vehicle can expect to endure? As in “a real kick in the pants” vs “slow, steady push”?
Also, isn’t material strength going to interact with the Max Acceleration figures? I’ve seen a few flight failures where the airframe tubes crumpled at the mach transition (and I understand that), and a few that failed way earlier than that (presumably from too many G’s?).
How do you guys approach analyzing if your airframe is capable of ‘taking the hit’ from a certain motor? Sim? Gut check? Seat of the pants? Hope for the best?
Or am I over analyzing it?