SpaceX Falcon 9/Dragon CRS SpX-1 MISSION GENERAL DISCUSSION

[yg1968]

Out of curiosity, had Falcon 9 [Edit: Dragon] not been able to get to ISS after the engine failure, would Dragon have come back safely to Earth?

Falcon 9 doesn't/didn't go to ISS. If Dragon achieved a minimal orbit, there was a contingency recovery zone near California after nearly one orbit that would allow recovery, probably also in case of failed solar deploy.

If it didn't manage to get into any kind of orbit, I'm not sure what the options were. Probably would drop somewhere near Europe in the Atlantic.

Yes, I obviously meant "if Dragon (not Falcon 9) could not get to the ISS". I had edited my post shortly after I wrote it but obviously not quickly enough. But thanks for your post. It answers my question.

[Proponent]

Imagine that your next United or Southwest flight to Chicago was forced to land in Milwaukee or Rockford or Cleveland instead, but the airline refused to refund your ticket, calling the flight a "success" because the airplane didn't crash.   

What if they get me to where I want to go, but they send my luggage somewhere else for a week?

I think you just summed up this launch to the T. +1

The luggage was placed in the wrong orbit....

Look at the bright side: this is a sign that SpaceX is beginning to develop airline-like operations.   And if you think going to the wrong airport and declaring the flight a success or not delivering your luggage within a week, etc., isn't consistent with airline-like operations, I have but one word for you: RyanAir.  If that doesn't mean anything to you, consider yourself lucky.  (RyanAir, for example, has been known to disclose only in the fine print that it was flying to an airport that wasn't actually in the same country as the advertised destination city.)

[Garrett]

So, let's say the engine gave up not 80 seconds but 10 seconds after liftoff and ... [blah, blah] ...

We're discussing CRS Spx-1 here, not some hypothetical mission. We could all invent scenarios where the F9 would have struggled to survive. The actual event that occurred was obviously not one of those scenarios.

[meekGee]

The labeling of the mission is really silly, since everyone knows the facts:  The primary was successful, the secondary was not.

What's important is what happened technically:

An engine failed.  This is the biggest thing here.  If it failed w/o an external cause, this is major issue, especially since they are so extensively tested.

The rocket excelled.  Overcame a failed engine, delivered the primary. IIUC, the secondary's failure was due to mission rules, not something that's inherent to the rocket.

That's all there is to it, really.  Now the focus should be looking for the root cause of the engine failure - and I don't think there's a post related to that in the last 20 pages of comments....

[cleonard]

For everyone debating "success or failure"

It's a subjective question.  Everyone will have a different definition.  The only ones that really matter are the customers.  As far as NASA is concerned it's a success.  I've not really read anything from Orbcomm, but I have a strong suspicion that they would say failure.

Debating personal positions on success or failure is pointless.

[Mader Levap]

SpaceX claims F9 is capable of single engine-out at any stage of launch and still deliver. (at least primary cargo, as we see with CRS-1 launch) So, if you believe SpaceX, they would manage with engine-out at 10 second.

A source for this would be useful, thanks! 

http://www.spacex.com/falcon9.php

This vehicle will be capable of sustaining an engine failure at any point in flight and still successfully completing its mission.

Note that some people believe SpaceX is outright lying in their publicly avaliable materials. (lie by omission is still lie)

L2 says otherwise and I trust L2 more than "some people".

Hey, I am in no position to command you whom you should believe.

[FuseUpHereAlone]

A few thoughts on this mission.

1.  The engine failure on the F9 first stage has highlighted the risks that companies take when they sign up as a secondary payload.  But it has also shown SpaceX's ability to still deploy a secondary payload in spite of this engine failure, although, not in the preferred orbit.

2.  Companies know that they run a higher risk by being a secondary payload, but they also get a better price.  Secondary payloads are good for companies like SpaceX, because it increases revenue.  So what can be done to make this a win-win for both the company that puts a secondary payload on a F9 and for SpaceX also?

3.  My thought is, would it be financially smart to increase the fuel capacity and fuel load of the secondary satellite, so that if it gets dropped off in too low an orbit, it can then raise itself to a functional orbit, thereby saving itself and the secondary mission?

1.  That depends on the extent that the payload can function in an orbit it wasn't designed for.  In many instances, a satellite placed in a useless orbit is about as functional as a satellite that blew up on the launch pad (except now you have to track a rather large piece of space debris).

2.  Well now secondary payloads are going to get a bit more expensive since their insurance premiums are now going to go up…and to answer your question: Make sure the launch vehicle works as planned.

3.  Sure you could, but that would come at the expense of other things that take up payload mass, such as transponders, antennas, solar panels, batteries, momentum wheels, etc.

[bob the martian]

An engine failed.  This is the biggest thing here.  If it failed w/o an external cause, this is major issue, especially since they are so extensively tested.

If it's a design flaw, it must be pretty subtle, since they've flown 30-some-odd 1Cs without incident (well, without an engine shredding itself, anyway).  IANARE, but I'd place money on a manufacturing defect that wasn't caught on the test stand.  Or, who knows, it could have been a confluence of a dozen little things that by themselves are no big deal, unless they all happen at the same time.  I can imagine there have been some pretty long and intense meetings in Hawthorne and McGregor over the last few days. 

Not expecting a quick answer out of SpaceX; I imagine this will take several weeks of analysis to pin down. 

There's another impetus for moving forward with flyback stages (assuming flyback would be possible after such an event); imagine being able to examine the hardware after the fact. 

[peter-b]

I've been thinking about it, and it sounds like the sort of thing that happens when you have a metallurgical defect (e.g. a streak of impurities in the metal blank that a component was machined from). Any materials engineers want to comment? I understand that these can be very difficult to directly test for...

[DigitalMan]

I see this differently than most of folks here:

You have a rocket with a total performance of 10X lets say:

- you require 8X to get a primary payload to its orbit
- you claim reliability and mitigation in case of failure, therefore you have the obligation to have lets say 2X in order to handle the worst case mitigation in order to fulfil primary

in this case, the 2X margin is a write-off if mitigations were not needed.  In my opinion, if you aren't selling your write-off margin for a secondary (or tertiary) you need a new sales team.  The question here is was this the scenario Orbcomm understood or did they expect the scenario below?

Variations on that are where you have enough dedicated performance for a secondary and separate secondary margin (write-off margin #2) for ensuring the secondary payload delivery.  Now you potentially have 2 write-off margins to sell.

There are enough gamblers on this planet eager to pay some measured amount for one of those write off margins.

It also is clear the F9v1.0 doesn't have the performance it needs.  But it is also clear it was not intended to be the production version, that's where the v1.1 comes in.  Perhaps that will have enough performance to handle both scenarios here.

[MP99]

2. The secondary mission failed. As a result of the loss of engine one the second stage was unable to execute a restart and the Orbcomm payload will likely not be usable to Orbcomm.

"unable to execute" is a bit strong. "chose not to execute" is the way I understood it. Of course, it made that choice because it figured out that it was not in a position to complete its mission.

NASA put strict rules in place for the secondary payload due to the potential for risk to the ISS and her crew.

SpaceX were "unable to execute" the orbit-raising burn for Orbcomm under the conditions quite rightly specified by NASA (primary customer), IE guaranteeing the safety of ISS. SpaceX accepted the payload understanding what would happen if there was a launcher under-performance. Orbcomm/Orbital (TBH, not sure which) paid for the launch knowing the conditions (I must presume), and they are also far from amateurs at this.

Neither SpaceX nor Orbcomm/Orbital had to put the secondary onto this flight, though Orbcomm may have been under schedule pressure to do so (speculation).

NASA specified requirements for the second burn, effectively anticipating that there might be an under-performance. ISTM this is all business-as-usual, and I imply no criticism by any of the above.

The secondary was a calculated risk on the fourth launch of this launcher (and hopefully priced as such to the customer).

cheers, Martin

[ugordan]

So, let's say the engine gave up not 80 seconds but 10 seconds after liftoff and ... [blah, blah] ...

We're discussing CRS Spx-1 here, not some hypothetical mission.

If you bother to go back in the post history, it's obvious we were discussing whether they were lucky this flight had enough performance to reach orbit. There are those who simply maintain luck had nothing to do with it. I maintain otherwise. I'm not attacking the reasoning that it's sound engineering that an engine failure didn't lead to a LOV event, I'm attacking the notion that the timing of the failure was not a factor in determining the outcome of the primary mission.

[cleonard]

I've been thinking about it, and it sounds like the sort of thing that happens when you have a metallurgical defect (e.g. a streak of impurities in the metal blank that a component was machined from). Any materials engineers want to comment? I understand that these can be very difficult to directly test for...

While something like this is certainly possible, I think it's more likely to be a manufacturing defect like a poor weld.  I doubt we will ever find out.  To really know the first stage would need to be recovered.  Was recovery of the stage part of the plan? 

I really doubt that there is any kind of disclosure requirement either.  SpaceX may just give a press release stating that they took some corrective measures. 

[Jim]

3.  My thought is, would it be financially smart to increase the fuel capacity and fuel load of the secondary satellite, so that if it gets dropped off in too low an orbit, it can then raise itself to a functional orbit, thereby saving itself and the secondary mission?

then it would be too heavy to be added to a mission

[ugordan]

SpaceX claims F9 is capable of single engine-out at any stage of launch and still deliver. (at least primary cargo, as we see with CRS-1 launch) So, if you believe SpaceX, they would manage with engine-out at 10 second.

A source for this would be useful, thanks! 

http://www.spacex.com/falcon9.php

This vehicle will be capable of sustaining an engine failure at any point in flight and still successfully completing its mission.

Note that some people believe SpaceX is outright lying in their publicly avaliable materials. (lie by omission is still lie)

Some people realize the fact that just about the only numerical value that has any relation to the current F9 v1.0 on that page is the vehicle diameter.

BTW, you missed the part about "will be capable" when picking which sections to bold.

[Jim]

SpaceX claims F9 is capable of single engine-out at any stage of launch and still deliver.

It can't during any part of second stage flight.

[kevin-rf]

While something like this is certainly possible, I think it's more likely to be a manufacturing defect like a poor weld.  I doubt we will ever find out.  To really know the first stage would need to be recovered.  Was recovery of the stage part of the plan? 

Well, that depends, if SpaceX is like old space and has close-out X-Rays, Photo's, and Ultra Sounds it might show up in them. It did with the Delta III RL-10 chamber breach.

Otherwise, who is up for a diving trip?

[Ben the Space Brit]

SpaceX claims F9 is capable of single engine-out at any stage of launch and still deliver.

It can't during any part of second stage flight.

Yes, obviously they are talking about the core stage burn.  I love that idea of a 'reasonable man interpretation'.

[MP99]

3.  My thought is, would it be financially smart to increase the fuel capacity and fuel load of the secondary satellite, so that if it gets dropped off in too low an orbit, it can then raise itself to a functional orbit, thereby saving itself and the secondary mission?

I suspect if the secondary had been much heavier, then it might have reduced the margins on the flight so that primary insertion would have failed to reach it's target, too.

cheers, Martin

Edit: I see Jim said as much above.

[Jim]

SpaceX claims F9 is capable of single engine-out at any stage of launch and still deliver.

It can't during any part of second stage flight.

Yes, obviously they are talking about the core stage burn.  I love that idea of a 'reasonable man interpretation'.

Not applicable to the general public or many on this site.  Also, not including the time from launch (10, 20 or 30 seconds or so) to the engine out capability is viable, the amount time of the ascent that is engine out capability is usable is less than 33%.