NASA's RS-25 EnginesWhat should a Discovery Program mission budget look like?What are the costs of the...
Can we track matter through time by looking at different depths in space?
Why is a very small peak with larger m/z not considered to be the molecular ion?
Has a sovereign Communist government ever run, and conceded loss, on a fair election?
Are all players supposed to be able to see each others' character sheets?
What is the generally accepted pronunciation of “topoi”?
Can I negotiate a patent idea for a raise, under French law?
PTIJ: Why does only a Shor Tam ask at the Seder, and not a Shor Mu'ad?
Why couldn't the separatists legally leave the Republic?
The meaning of ‘otherwise’
What's the 'present simple' form of the word "нашла́" in 3rd person singular female?
Can the alpha, lambda values of a glmnet object output determine whether ridge or Lasso?
What do you call someone who likes to pick fights?
Specifying a starting column with colortbl package and xcolor
I reported the illegal activity of my boss to his boss. My boss found out. Now I am being punished. What should I do?
From an axiomatic set theoric approach why can we take uncountable unions?
QQ Plot and Shapiro Wilk Test Disagree
Expressing logarithmic equations without logs
Do I really need to have a scientific explanation for my premise?
Vocabulary for giving just numbers, not a full answer
Trig Subsitution When There's No Square Root
Proving a statement about real numbers
Was it really inappropriate to write a pull request for the company I interviewed with?
Are small insurances worth it?
How do we create new idioms and use them in a novel?
NASA's RS-25 Engines
What should a Discovery Program mission budget look like?What are the costs of the various different engines in current use?How did they solve Saturn V pogo oscillation problems?Nasa's Orion program doesn't make senseHow will the SLS first stage be supplied with engines? Copy manufacturing the RS-25 or replacing it?Are cold gas thrusters viable for model rockets?How is chamber pressure and temperature determined for cold gas thrusters?What does this paper say is wrong (quantitatively and procedurally) with WISE & NeoWISE asteroid data?Where can I read further on the specs the South Korean engine for next month's sub-orbital test?How will the Gateway-before-boots sequence benefit US business, economic and technological development?
$begingroup$
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!
nasa engines sls ssme
New contributor
Mitch99 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
add a comment |
$begingroup$
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!
nasa engines sls ssme
New contributor
Mitch99 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
add a comment |
$begingroup$
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!
nasa engines sls ssme
New contributor
Mitch99 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
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!
nasa engines sls ssme
nasa engines sls ssme
New contributor
Mitch99 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Mitch99 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited 2 hours ago
Organic Marble
58.2k3159249
58.2k3159249
New contributor
Mitch99 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 3 hours ago
Mitch99Mitch99
254
254
New contributor
Mitch99 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Mitch99 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Mitch99 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
$begingroup$
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.

The hashed field is test experience, the solid lines are the ICD requirements.
$endgroup$
$begingroup$
Awesome! Exactly what I was looking for! Thank you!
$endgroup$
– Mitch99
58 mins ago
$begingroup$
@Mitch99 Since you're new to the site: If this answer is what you were looking for, please mark it as correct by clicking the gray checkmark beside it. And upvote if you have a mind to.
$endgroup$
– Organic Marble
55 mins ago
$begingroup$
Got it, thanks!!
$endgroup$
– Mitch99
26 mins ago
$begingroup$
So - since it takes ~4 seconds to get them to 100% thrust, do they then ignite them at T -4:00 seconds, and they count T -0:00 the time all of them are roughly at 100%, the SRBs get lit, and it's a "mission start"?
$endgroup$
– Mitch99
17 mins ago
$begingroup$
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
15 mins ago
add a comment |
Your Answer
StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "508"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Mitch99 is a new contributor. Be nice, and check out our Code of Conduct.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fspace.stackexchange.com%2fquestions%2f34726%2fnasas-rs-25-engines%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
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.

The hashed field is test experience, the solid lines are the ICD requirements.
$endgroup$
$begingroup$
Awesome! Exactly what I was looking for! Thank you!
$endgroup$
– Mitch99
58 mins ago
$begingroup$
@Mitch99 Since you're new to the site: If this answer is what you were looking for, please mark it as correct by clicking the gray checkmark beside it. And upvote if you have a mind to.
$endgroup$
– Organic Marble
55 mins ago
$begingroup$
Got it, thanks!!
$endgroup$
– Mitch99
26 mins ago
$begingroup$
So - since it takes ~4 seconds to get them to 100% thrust, do they then ignite them at T -4:00 seconds, and they count T -0:00 the time all of them are roughly at 100%, the SRBs get lit, and it's a "mission start"?
$endgroup$
– Mitch99
17 mins ago
$begingroup$
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
15 mins ago
add a comment |
$begingroup$
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.

The hashed field is test experience, the solid lines are the ICD requirements.
$endgroup$
$begingroup$
Awesome! Exactly what I was looking for! Thank you!
$endgroup$
– Mitch99
58 mins ago
$begingroup$
@Mitch99 Since you're new to the site: If this answer is what you were looking for, please mark it as correct by clicking the gray checkmark beside it. And upvote if you have a mind to.
$endgroup$
– Organic Marble
55 mins ago
$begingroup$
Got it, thanks!!
$endgroup$
– Mitch99
26 mins ago
$begingroup$
So - since it takes ~4 seconds to get them to 100% thrust, do they then ignite them at T -4:00 seconds, and they count T -0:00 the time all of them are roughly at 100%, the SRBs get lit, and it's a "mission start"?
$endgroup$
– Mitch99
17 mins ago
$begingroup$
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
15 mins ago
add a comment |
$begingroup$
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.

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

The hashed field is test experience, the solid lines are the ICD requirements.
edited 2 hours ago
answered 2 hours ago
Organic MarbleOrganic Marble
58.2k3159249
58.2k3159249
$begingroup$
Awesome! Exactly what I was looking for! Thank you!
$endgroup$
– Mitch99
58 mins ago
$begingroup$
@Mitch99 Since you're new to the site: If this answer is what you were looking for, please mark it as correct by clicking the gray checkmark beside it. And upvote if you have a mind to.
$endgroup$
– Organic Marble
55 mins ago
$begingroup$
Got it, thanks!!
$endgroup$
– Mitch99
26 mins ago
$begingroup$
So - since it takes ~4 seconds to get them to 100% thrust, do they then ignite them at T -4:00 seconds, and they count T -0:00 the time all of them are roughly at 100%, the SRBs get lit, and it's a "mission start"?
$endgroup$
– Mitch99
17 mins ago
$begingroup$
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
15 mins ago
add a comment |
$begingroup$
Awesome! Exactly what I was looking for! Thank you!
$endgroup$
– Mitch99
58 mins ago
$begingroup$
@Mitch99 Since you're new to the site: If this answer is what you were looking for, please mark it as correct by clicking the gray checkmark beside it. And upvote if you have a mind to.
$endgroup$
– Organic Marble
55 mins ago
$begingroup$
Got it, thanks!!
$endgroup$
– Mitch99
26 mins ago
$begingroup$
So - since it takes ~4 seconds to get them to 100% thrust, do they then ignite them at T -4:00 seconds, and they count T -0:00 the time all of them are roughly at 100%, the SRBs get lit, and it's a "mission start"?
$endgroup$
– Mitch99
17 mins ago
$begingroup$
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
15 mins ago
$begingroup$
Awesome! Exactly what I was looking for! Thank you!
$endgroup$
– Mitch99
58 mins ago
$begingroup$
Awesome! Exactly what I was looking for! Thank you!
$endgroup$
– Mitch99
58 mins ago
$begingroup$
@Mitch99 Since you're new to the site: If this answer is what you were looking for, please mark it as correct by clicking the gray checkmark beside it. And upvote if you have a mind to.
$endgroup$
– Organic Marble
55 mins ago
$begingroup$
@Mitch99 Since you're new to the site: If this answer is what you were looking for, please mark it as correct by clicking the gray checkmark beside it. And upvote if you have a mind to.
$endgroup$
– Organic Marble
55 mins ago
$begingroup$
Got it, thanks!!
$endgroup$
– Mitch99
26 mins ago
$begingroup$
Got it, thanks!!
$endgroup$
– Mitch99
26 mins ago
$begingroup$
So - since it takes ~4 seconds to get them to 100% thrust, do they then ignite them at T -4:00 seconds, and they count T -0:00 the time all of them are roughly at 100%, the SRBs get lit, and it's a "mission start"?
$endgroup$
– Mitch99
17 mins ago
$begingroup$
So - since it takes ~4 seconds to get them to 100% thrust, do they then ignite them at T -4:00 seconds, and they count T -0:00 the time all of them are roughly at 100%, the SRBs get lit, and it's a "mission start"?
$endgroup$
– Mitch99
17 mins ago
$begingroup$
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
15 mins ago
$begingroup$
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
15 mins ago
add a comment |
Mitch99 is a new contributor. Be nice, and check out our Code of Conduct.
Mitch99 is a new contributor. Be nice, and check out our Code of Conduct.
Mitch99 is a new contributor. Be nice, and check out our Code of Conduct.
Mitch99 is a new contributor. Be nice, and check out our Code of Conduct.
Thanks for contributing an answer to Space Exploration Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fspace.stackexchange.com%2fquestions%2f34726%2fnasas-rs-25-engines%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown