Do you have these documents?
No it doesn’t.
The museum is basically putting what the military told them on the placard.
The fact that you think an old museum placard is more accurate than a NASA technical handbook that gets revised every few years is amazing to me.
The burn time and thrust values that they are using is based on old/incorrect burn time and thrust values.
Burn time should be changed from 5+21 seconds to 6+18 seconds which IS a significant difference.
Thrust values also should get increased according the revised values (I’m not saying they should use those exact values, but they should apply the same % of increase).
The museum is the missile range, and they have access to the same technical documents. Email them asking about the accuracy.
The fact that you’re using the NASA data from 20+ year old shelved motors in unknown atmospheric conditions especially when two different claims are wildly off from what was quoted previously is… amazing to me.
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That is hardly the conclusive explanation.
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Do you not think the earlier one may have just aged poorly?
If the previous values were for poorly aged rocket motors, it would be all the more reason to give it the revised thrust and burn time values (that were calculated for the “not so poorly” aged rocket motors).
You’re not understanding what I was saying.
Also a 38% increase in peak numbers means nothing because we know the sustainer is progressive as I stated earlier. It may actually be “worse”.
Elaborate please
The sustainer is progressive. That means thrust increases over time until burnout. The peak numbers given do not tell us it has a direct 38% increase in performance, rather that the peak thrust output is a bit higher. The initial and subsequent NASA calculations were not necessarily wrong… at least that is not “obvious” as you claim. What likely happened was they tested a poorly aged motor as well as a better example later on and revised it.
We also do not know how they calculated it or what the accuracy of the calculation was. What we do know is that the official museum placard states 5s boost and 21s sustained which is in-line with the expected performance and propellant mass / fractions shown in the cutaway.
Could you move this information to the correct thread and link the sources?
Of the charts you posted, the R-27ER fails to reach the speeds given in the top one in-game and the second one looks dubious at best. Off a glance appears to lack required deltaV to reach the top speeds shown in the first chart.
It definitely is not worse because if you compare the Apogee-Payload chart between the two versions, it has actually slightly improved.
As compared to the 5s boost and 21s sustained? Follow along.
Yes, I have linked both versions in the report.
Just go to the Improved Orion section and compare the Apogee-Payload charts.
I was discussing as compared to the original fresh motor with the claimed 5s boost and 21s sustained, not the initial worse performing NASA motor.
The museum placard doesn’t provide thrust values anyways. So you can’t really say the NASA data from either versions are worse or better than the placard.
The thrust data is derived from the sounding rocket accelerations claiming 5s boost 21s sustained
Can we please see your calculations?
They stated 19.4 and 20G for the accelerations of the rocket. Calculating the acceleration and weight brings us to 85-95kN rough figures. The math isn’t hard.
Please, do the math and show us how you calculate the boost and sustain thrust from those figures.