Happy New Year, Rocket Sages!
I have been using OpenRocket for the last few days for the FIRST time to create a sim of a modified Estes Saturn V (2157) with a 5 engine cluster and the program is SO awesome that I am already almost finished (just double checking all measurements for accuracy and "touching up" left to do. I have tried using the trial version of RockSim a couple of times (once recently), but the GUI is not nearly as intuitive for me as OR is. Suffice it to say that I am absolutely thrilled with OR and my only hope it is accurate with launch simulations with differing engines combinations to about 10% or so. If this proves to be the case, then I just got the best Christmas present for myself than I have in many, many years (for free)!
So, the "problem" that I am experiencing is this:
When I sim any of the 5 engines as one with a "0" delay, it appears that OR considers the zero delay as an EJECTION event, causing the program to report a highly unsafe parachute deployment speed (as the others with a true ejection delay are still under power or coasting).
My understanding is that Estes "0" delay engines (mainly designed for staging) do not have an ejection charge at all, but rather just "burn through" to ignite the next stage engine.
I definitely want redundancy for ejection purposes in case one or more of the engines in the cluster do not ignite, so I would not use say a 4 "0" + only one with an ejection charge cluster configuration. But I do have quite a few more "0" engines on hand than any other type, so would like to use up one or two with each five-clustered launch.
There is little doubt that even one ejection charge with deploy the chutes, but I am concerned that if FIVE charges go off at once that it my cause a catastrophic tube failure so it would be great to start with a few launches of only 3 (or 4 max) with ejection charges.
Am I missing something, or is this an OR abnormality? It would be great to successfully sim different configurations using zero-delayed engines.
If any of you sages can help, I'd appreciate it!
BTW, this is why I have recently tried to use RockSim again... to check to see if it allows "0" delay engines to be used in a cluster without "thinking" that there was an ejection charge too, but it was way too cumbersome to recreate the Saturn V compared to OR!
I have successfully sim'd many, many engine combinations (about 10) in OR with ejection occurring at less than 5 m/s velocity, so I would think substituting a "0" delay engine or two would result in an early failure due to premature ejection (not pun intended).
Thanks for you help ahead of time!
Joe Mac
I have been using OpenRocket for the last few days for the FIRST time to create a sim of a modified Estes Saturn V (2157) with a 5 engine cluster and the program is SO awesome that I am already almost finished (just double checking all measurements for accuracy and "touching up" left to do. I have tried using the trial version of RockSim a couple of times (once recently), but the GUI is not nearly as intuitive for me as OR is. Suffice it to say that I am absolutely thrilled with OR and my only hope it is accurate with launch simulations with differing engines combinations to about 10% or so. If this proves to be the case, then I just got the best Christmas present for myself than I have in many, many years (for free)!
So, the "problem" that I am experiencing is this:
When I sim any of the 5 engines as one with a "0" delay, it appears that OR considers the zero delay as an EJECTION event, causing the program to report a highly unsafe parachute deployment speed (as the others with a true ejection delay are still under power or coasting).
My understanding is that Estes "0" delay engines (mainly designed for staging) do not have an ejection charge at all, but rather just "burn through" to ignite the next stage engine.
I definitely want redundancy for ejection purposes in case one or more of the engines in the cluster do not ignite, so I would not use say a 4 "0" + only one with an ejection charge cluster configuration. But I do have quite a few more "0" engines on hand than any other type, so would like to use up one or two with each five-clustered launch.
There is little doubt that even one ejection charge with deploy the chutes, but I am concerned that if FIVE charges go off at once that it my cause a catastrophic tube failure so it would be great to start with a few launches of only 3 (or 4 max) with ejection charges.
Am I missing something, or is this an OR abnormality? It would be great to successfully sim different configurations using zero-delayed engines.
If any of you sages can help, I'd appreciate it!
BTW, this is why I have recently tried to use RockSim again... to check to see if it allows "0" delay engines to be used in a cluster without "thinking" that there was an ejection charge too, but it was way too cumbersome to recreate the Saturn V compared to OR!
I have successfully sim'd many, many engine combinations (about 10) in OR with ejection occurring at less than 5 m/s velocity, so I would think substituting a "0" delay engine or two would result in an early failure due to premature ejection (not pun intended).
Thanks for you help ahead of time!
Joe Mac
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