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I am developing a FSX-based space flight simulator FSX SpacePort. I've been trying to get the detailed specs on NASA's RS-25 engine, namely, what were the ramp-up times for this engine? As in, how long did it take from ignition to full thrust?

Thanks!

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A good assumption is that the startup sequence is very similar to the SSME. Here is some SSME startup data showing the time you asked about from the Rocketdyne Pocket Data Book. Eventually the SLS will be using RS-25Es which are somewhat different from the SSME, but my guess is that the start sequence won't change much if at all.

enter image description here

The hashed field is test experience, the solid lines are the ICD requirements.

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  • $\begingroup$ Awesome! Exactly what I was looking for! Thank you! $\endgroup$ – Mitch99 Mar 10 at 23:33
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    $\begingroup$ I only know about shuttle, but there the start command was send at ~T-5 seconds, which gave time for the SSMEs to light, the "twang" to settle, and then the SRBs lit at, yes, T-0. SLS won't have the "twang" to deal with because its engines are axially mounted. $\endgroup$ – Organic Marble Mar 11 at 0:16
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    $\begingroup$ That's correct. $\endgroup$ – Organic Marble Mar 11 at 18:57
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    $\begingroup$ @MagicOctopusUrn you are correct of course, but the one time - the one time - that Johnny Robinson actually accepted one of my answers, you posted this, he took off the acceptance, and never accepted another one. sigh $\endgroup$ – Organic Marble Mar 11 at 19:02
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    $\begingroup$ @OrganicMarble not a biologist eh-- if you can't tell a bear and an octopus apart ;P? Nothing to apologize for-- sounded like something I'd do hah. $\endgroup$ – Magic Octopus Urn Mar 12 at 14:11

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