SpaceX F9 : Crew Dragon In-Flight Abort Test : Jan. 19, 2020 : Discussion

[envy887]

“Increasingly cautious NASA” is testing Orion on a ballistic missile, similar to Apollo tests. SpaceX would be just fine testing Dragon without a second stage. It’d be closer to the real thing than what NASA is doing with Orion.

Not to mention, Starliner isn't even doing an in-flight abort test... at all.

Because it wasn't a NASA requirement at all.

[clongton]

The Abort will be triggered at Max-Q during 1st stage operation.

That wasn't his question.  There no doubt whatsoever that the abort will be triggered during stage one operation, at or immediately after max-Q.  The only real question is whether the stack will include a second stage so that the test may be more true to actual flight conditions.

The only flight condition that needs to be met is max-q. SpaceX will not waste an upper stage when the still firing 1st stage will be destroyed by the FTS after the Dragon aborts.

So no. There will not be an upper stage.

[Coastal Ron]

The only flight condition that needs to be met is max-q. SpaceX will not waste an upper stage when the still firing 1st stage will be destroyed by the FTS after the Dragon aborts.

So no. There will not be an upper stage.

Is this an opinion, or is it based on facts or intel we have?

And it certainly makes sense not to waste a 2nd stage, but I just want to understand if we're still dealing with facts or speculation, informed or otherwise.

[rsdavis9]

The only flight condition that needs to be met is max-q. SpaceX will not waste an upper stage when the still firing 1st stage will be destroyed by the FTS after the Dragon aborts.

So no. There will not be an upper stage.

Is this an opinion, or is it based on facts or intel we have?

And it certainly makes sense not to waste a 2nd stage, but I just want to understand if we're still dealing with facts or speculation, informed or otherwise.

Also do we know for sure that the booster has to be destroyed or can it then do a regular landing procedure.

[whitelancer64]

The only flight condition that needs to be met is max-q. SpaceX will not waste an upper stage when the still firing 1st stage will be destroyed by the FTS after the Dragon aborts.

So no. There will not be an upper stage.

Is this an opinion, or is it based on facts or intel we have?

And it certainly makes sense not to waste a 2nd stage, but I just want to understand if we're still dealing with facts or speculation, informed or otherwise.

Also do we know for sure that the booster has to be destroyed or can it then do a regular landing procedure.

There's no point in wasting a 2nd stage, there will need to be an adapter of some kind mounted on the interstage for the Dragon connections.

There's no point in wasting a first stage, either, if that can be avoided. I would suspect they would have the booster programmed to RTLS just in case it survives.

Aerodynamic forces should break apart the booster, but we've been surprised before (Blue Origin's abort test).

[abaddon]

“Increasingly cautious NASA” is testing Orion on a ballistic missile, similar to Apollo tests. SpaceX would be just fine testing Dragon without a second stage. It’d be closer to the real thing than what NASA is doing with Orion.

Not to mention, Starliner isn't even doing an in-flight abort test... at all.

Because it wasn't a NASA requirement at all.

The point, if you've been following this discussion, was that having an in-flight abort that exactly matches the flying configuration is not a requirement, and not only that, having an in-flight abort is not a requirement.  It's an addition to the rebuttal to the idea that "Increasingly cautious NASA" would require the exact parameters of a launch to be diligently replicated for the in-flight abort to be considered valid.

Your point is correct, but unrelated, and something I think most of us already knew, and is really obvious.  If NASA required an in-flight abort, Starliner would be doing one.

[chrisking0997]

I would think at this point if they arent going to use an upper stage, at the very least there will be a boilerplate one.  Unless I missed the news of the TEL being modified to handle D2 at a different height?

[envy887]

I would think at this point if they arent going to use an upper stage, at the very least there will be a boilerplate one.  Unless I missed the news of the TEL being modified to handle D2 at a different height?

This is a good question, since the TEL currently requires a upper stage in order to hold F9 horizontally or to raise it vertical. They could either add a lower support+gripper arms, or maybe use a crane to raise the booster vertical on the pad.

[chipguy]

There's no point in wasting a 2nd stage, there will need to be an adapter of some kind mounted on the interstage for the Dragon connections.

There needs to be a mechanical adaptor between the first stage and the Dragon.
Rather than engineer an one-off adaptor the simplest thing to do is use a second
stage. It doesn't need to be functional other than electrical pass through (and
perhaps not even not that) so can be stripped down - no engine, avionics etc).
You probably want the full weight approximated so fill the tanks with water.

[whitelancer64]

There's no point in wasting a 2nd stage, there will need to be an adapter of some kind mounted on the interstage for the Dragon connections.

There needs to be a mechanical adaptor between the first stage and the Dragon.
Rather than engineer an one-off adaptor the simplest thing to do is use a second
stage. It doesn't need to be functional other than electrical pass through (and
perhaps not even not that) so can be stripped down - no engine, avionics etc).
You probably want the full weight approximated so fill the tanks with water.

Its weight wouldn't matter, but it would need to be pressurized for stiffness, to handle the flight loads.

[chipguy]

There's no point in wasting a 2nd stage, there will need to be an adapter of some kind mounted on the interstage for the Dragon connections.

There needs to be a mechanical adaptor between the first stage and the Dragon.
Rather than engineer an one-off adaptor the simplest thing to do is use a second
stage. It doesn't need to be functional other than electrical pass through (and
perhaps not even not that) so can be stripped down - no engine, avionics etc).
You probably want the full weight approximated so fill the tanks with water.

Its weight wouldn't matter, but it would need to be pressurized for stiffness, to handle the flight loads.

It would if you wanted max-Q to happen at the same time in flight and altitude
as a real launch. Otherwise the you have to throttle engines on the first stage
and check the effect of COG/MOI changes on flight dynamics and guidance.

[DistantTemple]

One of my hopes and dreams was that SpaceX would eventually take one of the recovered but not destined to be reused for a mission Dragons, and a recovered first stage and just huck that Dragon up as high as it could go with the first stage boost, leaving enough fuel to re-land the booster, and skip a second stage.  Isn't that basically free practice? 
   I realize there are huge problems with that, biggest probably being that there is currently no known way to attach a Dragon directly to a first stage, much less release it reliably at any particular desirable point.

Actually, there is. They need that for the in-flight abort test.

Aren't SX going to fly the in flight abort with the flight hardware? i.e. a stage 2 etc. so it is a valid as possible?

They are testing the capsule, not the rocket. Look at how other capsules like Apollo and Orion did in flight abort tests.

And..............

That wasn't his question.  There no doubt whatsoever that the abort will be triggered during stage one operation, at or immediately after max-Q.  The only real question is whether the stack will include a second stage so that the test may be more true to actual flight conditions.

actual configuration of the booster is meaningless as long as it provides the right flight conditions.  Having a second stage or not, has no bearing on the test.

And I could quote loads more good responses, and opinions... like compatability with GSE, destruction of the booster by FTS, 

So what is my question? This was what I wrote "Aren't SX going to fly the in flight abort with the flight hardware? i.e. a stage 2 etc. so it is a valid as possible?" because I assumed someone would say "this has been discussed at..." And I wasn't ready to research it.

So for clarity:
1. Has this been discussed and resolved elsewhere on NSF, and where? Is it a closed case?
2. What is known about the in-flight-abort?
3. Some of you say categorically it will be close to maxQ.
4. There is discussion over NASA requirements. Although NASA didn't "require this test" to have best value I assume SX would get as much NASA input as possible. With booster configuration its "seven launches of the booster configuration that will fly crew". So..
5. What exactly is being tested? Is it "end-to-end" Is it "flight configuration" is it separation, descent and landing at a specific speed/position? etc. Without the question we cannot have an answer! Some of you have been clear, are you speaking facts?

IMO SX should make it as real as possible. This appears to make it the most valid test of the actual crew tests. It also avoids constructing things and making alterations that cost and may introduce new errors. And as for cost, if they are going to do the test they might as well do it properly, then there will be less holes to pick in it afterwards.

If this is all elsewhere just post the link. Thank you all for the great responses to an off-hand query.

[whitelancer64]

There's no point in wasting a 2nd stage, there will need to be an adapter of some kind mounted on the interstage for the Dragon connections.

There needs to be a mechanical adaptor between the first stage and the Dragon.
Rather than engineer an one-off adaptor the simplest thing to do is use a second
stage. It doesn't need to be functional other than electrical pass through (and
perhaps not even not that) so can be stripped down - no engine, avionics etc).
You probably want the full weight approximated so fill the tanks with water.

Its weight wouldn't matter, but it would need to be pressurized for stiffness, to handle the flight loads.

It would if you wanted max-Q to happen at the same time in flight and altitude
as a real launch. Otherwise the you have to throttle engines on the first stage
and check the effect of COG/MOI changes on flight dynamics and guidance.

Max Q, the Q is a variable - it only means the point of "maximum dynamic pressure" the precise time and altitude of that event changes from launch to launch.

The same dynamic effects can be achieved at different altitudes. The only thing that matters for the test is that the pressure on the exterior of the capsule is the same as would be experienced in normal flight.

That's why Orion is using a Peacekeeper 1st stage for its in-flight abort test.

[kevindbaker2863]

If the IFA Test is to be a demonstration of D2 ability to prevent LOC at the conditions that would have the highest chance for a LOC event.  use a working S2  fill it with propellant and then use the S2 FTS to initiate a catastrophic event.   when Dragon and the simulated test humans inside are shown to have survived this worst case scenario so that there would be no LOC then you have set bar very high for safety and Risk reduction.  is there a different set of conditions that have a higher risk of LOC during launch than this scenario?   

[whitelancer64]

So what is my question? This was what I wrote "Aren't SX going to fly the in flight abort with the flight hardware? i.e. a stage 2 etc. so it is a valid as possible?" because I assumed someone would say "this has been discussed at..." And I wasn't ready to research it.

So for clarity:
1. Has this been discussed and resolved elsewhere on NSF, and where? Is it a closed case?
2. What is known about the in-flight-abort?
3. Some of you say categorically it will be close to maxQ.
4. There is discussion over NASA requirements. Although NASA didn't "require this test" to have best value I assume SX would get as much NASA input as possible. With booster configuration its "seven launches of the booster configuration that will fly crew". So..
5. What exactly is being tested? Is it "end-to-end" Is it "flight configuration" is it separation, descent and landing at a specific speed/position? etc. Without the question we cannot have an answer! Some of you have been clear, are you speaking facts?

IMO SX should make it as real as possible. This appears to make it the most valid test of the actual crew tests. It also avoids constructing things and making alterations that cost and may introduce new errors. And as for cost, if they are going to do the test they might as well do it properly, then there will be less holes to pick in it afterwards.

If this is all elsewhere just post the link. Thank you all for the great responses to an off-hand query.

It has been discussed at great length here, not sure which threads specifically.

*edit* there's a thread here:

https://forum.nasaspaceflight.com/index.php?topic=45279.25

Mods: probably all this conversation should be shifted there.

*/edit*

There hasn't been a recent statement from SpaceX about what they intend to do for the in-flight abort. There are several old statements that no longer apply.

For example, SpaceX has said before that the in-flight abort will be done with the 3-engined "F9R Dev 2" vehicle, but they aren't doing that anymore, and that it would be done at "max Drag" rather than "max Q," which is a subtle distinction. Max Drag occurs nearly the same time as Max Q. For the purposes of most discussions, like here, they're near enough to the same thing as to make no difference.

NASA did not require any abort tests from either Commercial Crew provider (In my opinion, they should have). Boeing chose to make a pad abort one of their milestones. SpaceX chose to have both a pad abort and in-flight abort milestones.

The only thing being tested is the Dragon's capability to fire its LAS and separate from the rocket in a worst-case scenario in terms of aerodynamic forces on the vehicle. Nothing else really matters for the abort portion of the test, though presumably a successful recovery of the Dragon at the expected location is among the success criteria, since it was for the pad abort test.

[whitelancer64]

If the IFA Test is to be a demonstration of D2 ability to prevent LOC at the conditions that would have the highest chance for a LOC event.  use a working S2  fill it with propellant and then use the S2 FTS to initiate a catastrophic event.   when Dragon and the simulated test humans inside are shown to have survived this worst case scenario so that there would be no LOC then you have set bar very high for safety and Risk reduction.  is there a different set of conditions that have a higher risk of LOC during launch than this scenario?

Completely unnecessary. No in-flight abort tests have ever been done this way, and there's no reason to start now.

It would only serve to make the test much more expensive and more complicated than it needs to be.

[DistantTemple]

snip...
Why?...
Because the last thing we need... is the internet and NASA arguing later it was not a legitimate worse case test... 
MAKE IT worst case... screw trying to save S1...
Blow S2 Amos style right at Max-Q (high in the stack, worst case) and watch Dragon hopefully do it's job outrunning the carnage in it's rear view mirror...
snip...
Just blow it all to heck at Max-Q and show that it works... period... 

(my bold)
Yes I thought that.... and now you say it, it is a real Elon kind of spectacle! Its a bit mad like flame throwers, it laughs at previous accidents, and kinda says "we take explosions in our stride... we even do them on purpose" and in an everyday way they have tested it for real in an uncomplicated way that appeals to the general public... and also scored another notch over Boeing!

[vaporcobra]

With the uncrewed demo now NET "end of the year", the In-Flight Abort has to be NET 2019, probably late Q1.

[mme]

With the uncrewed demo now NET "end of the year", the In-Flight Abort has to be NET 2019, probably late Q1.

"End of the year" has been retracted and replaced with "later this year" so I would not assume anything at this point.

[Nehkara]

Especially given that alongside their retraction they linked back to the previously known dates.  (i.e. August 2018 for both uncrewed demo flights)