# How do solid rocket motor thrust curves work in Realism Overhaul?

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I'd like to be able to create solid motor configs that have 100% thrust all the time in order to reduce gravity drag for orbital launch vehicles. However, I don't know how the thrust curves in the engine configs are structured. For instance, the AJ-260 FL:

```thrustCurve
{
key = 1 0.554323725 -12 -12
key = 0.99425197 0.692904656 -4 -4
key = 0.851189892 0.859201774 -0.952083496 -0.952083496
key = 0.681175941 0.985310421 -0.531426454 -0.531426454
key = 0.63542801 1 0 0
key = 0.498184216 0.985310421 0.255306394 0.255306394
key = 0.323060905 0.914634146 0.285245267 0.285245267
key = 0.157006708 0.88691796 0.31677097 0.31677097
key = 0.03821409 0.831485588 3 3
key = 0.023086798 0.44345898 39.42093859 39.42093859
key = 0.00322197 0.138580931 7 7
key = 0.0001 0.0005 0 7
}```

wat.  I think the first two columns are referring to the propellant quantity remaining and thrust, respectively, but what are the latter two columns? I really don't want to do this, but... @NathanKell? @Phineas Freak? @JadeOfMaar? @Mecripp? Can you help?

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@Grant Exploit I believe I met with this node ( thrustCurve {} ) before but I've never tried it myself, and your description sounds right. What I can help you with is what the 3rd and 4th numbers are in each key. These are the Tangent In and Tangent Out. They control the angle at which the curve flows into and out of that point. I strongly advise you get this mod to help you with that, and get to know it (it may be troublesome but it's available). There is no room to guess the values you put here and expect to get what you want.

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Thanks @JadeOfMaar! I'll take a look at that mod. I'll experiment on my 100% idea first—I don't think the tangent curves will matter for that.

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@JadeOfMaar's reply is spot on: find the SRM datasheet that includes the thrust curve graph, install Amazing Curve Editor and try to recreate it. It is going to be a bit messy and might take multiple tries to get it right but i do not see any other way to easily create curves (not at least without using external programs).

Also

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