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SpaceX Launch To International Space Station Delayed For Code Tweaks

timothy posted about 2 years ago | from the ones-where-the-zeroes-were dept.

ISS 97

RogerRoast writes "The first private spaceship launch to the International Space Station has been delayed, possibly by at least a week, the vehicle's makers announced Monday. The commercial spaceflight company SpaceX was set to launch its Dragon capsule atop a Falcon 9 rocket April 30 from Cape Canaveral Air Force Station in Florida." The article quotes SpaceX lead Elon Musk's twittered explanation: "Am pushing launch back approx a week to do more testing on Dragon docking code. New date pending coordination with @NASA."

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97 comments

Sure... (0, Flamebait)

Anonymous Coward | about 2 years ago | (#39780759)

Blame it on the software... Did anyone test the software before yesterday?

Re:Sure... (4, Funny)

azalin (67640) | about 2 years ago | (#39780777)

Maybe the just noted half the libraries were in metric

Re:Sure... (0)

Anonymous Coward | about 2 years ago | (#39780935)

Yes, but which half?

Re:Sure... (3, Funny)

K. S. Kyosuke (729550) | about 2 years ago | (#39781147)

Yes, but which half?

An imperial half.

Re:Sure... (0)

Anonymous Coward | about 2 years ago | (#39787671)

So, let me get this straight: You're actually talking about an imperial half of metric Libraries of Congress? How much is this in Minivans [slashdot.org], please?

Re:Sure... (1)

jellomizer (103300) | about 2 years ago | (#39781367)

Having worked for commercial industry, this is code words for, we are not done coding it yet.
 

Re:Sure... (2)

craigminah (1885846) | about 2 years ago | (#39781559)

I too worked in the space launch business and delays always are lastg minute because they cost so much and everyone is waiting for someone else to be the reason for the delay. If there was a delay due to cryo problems the coding issue would never come to light as they'd feverishly work to get it done while launch is delayed due to "cryo issues."

Re:Sure... (1)

Tmann72 (2473512) | about 2 years ago | (#39783857)

I'm pretty sure they want to make absolutely sure it doesn't fail. Considering the fact the capsule costs a ton of money to make, and the historic factor here. If they fail now it could potentially destroy the companies finances and reputation. I highly doubt this is so simple as being 'not done coding yet.' Its more likely they decided to do another round of unit tests to make absolutely sure everything is going to work.

Release schedules (3, Insightful)

azalin (67640) | about 2 years ago | (#39780811)

When is any project ever on time? It's not like they can release beta grade software and release an automatic update to fix it later. If they mess this up, it's going to cost them and maybe, just maybe the engineers plea for proper testing has been answered (a little late though)

Re:Release schedules (2)

Infiniti2000 (1720222) | about 2 years ago | (#39780907)

...and maybe, just maybe the engineers plea for proper testing has been answered (a little late though)

Not late. Hopefully, just in time. Late would be after launch and, then uh oh...

The last project that was on time... (0)

Anonymous Coward | about 2 years ago | (#39782809)

...was when God created Existence. From idea conception to final rollout, it took exactly 6 days to implement.

Re:The last project that was on time... (0)

Anonymous Coward | about 2 years ago | (#39783155)

... and a crummy job he did !

Elon Musk (0)

XPeter (1429763) | about 2 years ago | (#39780813)

He's doing an absolutely fantastic job with his two post-paypal start-ups. I already have quite a few shares of Tesla, and when SpaceX goes public I'll pick up as well.

Re:Elon Musk (2)

Anonymous Coward | about 2 years ago | (#39780845)

He's doing an absolutely fantastic job with his two post-paypal start-ups. I already have quite a few shares of Tesla, and when SpaceX goes public I'll pick up as well.

not sure telsa is a wise investment choice, always seem to be on the brink of going broke

Re:Elon Musk (1, Interesting)

XPeter (1429763) | about 2 years ago | (#39780875)

They already have thousands of pre-orders for the Model S, and I'm betting they'll get even more for the Model X

Re:Elon Musk (1)

X0563511 (793323) | about 2 years ago | (#39785935)

That's the perfect time, if you think the risk is acceptable. Things don't get much more rock bottom than rock bottom.

The trick is to be patient and not pull out, consider the money you invested lost already, and put it out of your mind. This way, the worst that will happen is nothing.

Re:Elon Musk (0)

Anonymous Coward | about 2 years ago | (#39781337)

So, Slashdot is an "investment" site now? Look, if I want to read bullshit rah-rah-rah posts by crooks and idiots who don't even know basic accounting, I'll go to "Motley Fool" or "The Street".

Yikes! (4, Insightful)

sycodon (149926) | about 2 years ago | (#39780819)

"Last minute code tweaks" never go well.

Re:Yikes! (5, Funny)

Like2Byte (542992) | about 2 years ago | (#39780869)

heh.

Reminds me of that song, "99 instances of bugs in the code..."

99 instances of bugs in the code...
99 instances of bugs, ....
code one out, mark it out,
106 instances of bugs in the code...
106 instances of bugs in the code...
106 instances of bugs, ....

The Last Bug Guy worked for NASA (1)

RobertLTux (260313) | about 2 years ago | (#39784287)

but hey at least they had a body to bury "face down 9 edge first" since a number of times in NASAs case they didn't.

Re:Yikes! (1)

Megane (129182) | about 2 years ago | (#39781005)

But they're a lot worse when you have to send updates to an already deployed system. LEO is one of the remotest of remote sites. It's kind of hard to get the janitor to walk up and to push the reset button for you. I think a week delay to get it right is a lot better than "ship it and we'll push an update later".

Re:Yikes! (1)

sycodon (149926) | about 2 years ago | (#39782249)

"Last minute code tweak" to me, means changing the code at the very last minute.

They say a week, but it seems that with something so complex any change in code would require a complete rerunning of all of the regression tests, a complete detailed examination of the results plus a review by whatever group provides oversight.

Try to get that all done in one week under a drop dead deadline...recipe for disaster.

Re:Yikes! (1)

gstrickler (920733) | about 2 years ago | (#39781867)

What about last minute code tweaks that save a ~$1M account, and work so well that within 3mos are rolled out to 90% of customers?

I agree with you, but never is a strong word.

Re:Yikes! (1)

sycodon (149926) | about 2 years ago | (#39781943)

I'd call that pulling your ass out of the fire at the very last minute.

Re:Yikes! (1)

gstrickler (920733) | about 2 years ago | (#39782203)

Not exactly. The bug was on their end, I just added a feature that avoided their bug, and it was a feature that lots of others found reduced confusion so everyone wanted it.

Re:Yikes! (1)

sycodon (149926) | about 2 years ago | (#39782271)

Well, You Da Man in that case.

Strictly speaking though, your tweak should have under gone the full test and review process. But then, while we read about those things, very few companies actually have them.

Re:Yikes! (2)

gstrickler (920733) | about 2 years ago | (#39782653)

In theory, yes, it should have gone through more extensive testing. But business timelines don't always allow that.

I cultivated a great relationship with our QA dept. While I had the ability and authority to bypass QA and put something in production, I only did that in one or two emergencies over 16 years. The rest of the time, I made sure my code went through QA, even if it was an abbreviated test, and I (almost) always gave them a list of things I thought they should test, to which they would add their own tests. And I never gave them a hard time or had a bad attitude about them finding bugs or suggesting improvements to the work flow, UI, wording, etc. I gave them code with few bugs, they gave me valuable feedback and kept most of my bugs from reaching production.

JMHO, but that's how development & QA should work.

Re:Yikes! (1)

monoqlith (610041) | about 2 years ago | (#39790009)

Last minute bug fixes are one thing. Last minute features are another.

Last week I made a last-minute feature add that not only saved my job(the VP changed his mind about me), but got me promoted.

I don't mind saying: It was legendary.

Re:Yikes! (1)

FullBandwidth (1445095) | about 2 years ago | (#39787963)

True - but where in the article does it say anything about making any code tweaks? All I saw was they want to do more hardware-in-the-loop testing and review the data. If all that passes muster, no code will change and presumably they will be go for launch. If it doesn't pass, THEN they may consider standing down to make code changes. Or, change operational procedures or ground software or ask for a waiver or any of a number of corrective actions. Maybe MSNBC updated the article after you read it ... or maybe my browser hid page 2 or something? The only mention of "code tweaks" is in the incorrect /. headline. Cheers

Better to fix it first (5, Insightful)

pablo_max (626328) | about 2 years ago | (#39780829)

Better they found it now and missed the deadline than went anyhow and exploded. You do not get too many second chances in space.

Re:Better to fix it first (4, Informative)

joh (27088) | about 2 years ago | (#39781015)

Has nothing to do with "exploding". The problem is the automatic docking (actually berthing) and I've read they still have too many false emergency aborts in testing. They don't want to go all the way to the ISS just to have it pull back for no good reason automatically.

Anyway, if they have their software and their testing not ready one week before launch, this isn't good at all. They should better put if off for a month or so.

Re:Better to fix it first (0)

Anonymous Coward | about 2 years ago | (#39781227)

This. We deliberately sent old HW up, so it was already rigorously tested.I mean, the spaceshuttle ran on a 386 [cpushack.com]. But the software we send up has its final lines added while the engines are heating up?

That's just wrong.

Re:Better to fix it first (4, Funny)

jamesbulman (103594) | about 2 years ago | (#39781249)

I've checked in the fix...

//bugfix: Stop abort code messing up docking
//if(doAbort)
//{
// DoAbort();
//}

Re:Better to fix it first (1)

lenorin (1203022) | about 2 years ago | (#39789733)

Just wanted you guys to know, the SpaceX flight software group are laughing our asses off right now. Thanks.

Re:Better to fix it first (1)

luis_a_espinal (1810296) | about 2 years ago | (#39781295)

Better they found it now and missed the deadline than went anyhow and exploded. You do not get too many second chances in space.

In Space No One Can Hear You Scream.

Re:Better to fix it first (1)

X0563511 (793323) | about 2 years ago | (#39786087)

Not so much exploding, but aborting for no real reason and wasting lots of time and funds. (or taken the other way, not aborting and damaging the ISS)

Where is their spirit of adventure? (5, Funny)

fuzzyfuzzyfungus (1223518) | about 2 years ago | (#39780863)

Cowards!!! Launch early, launch often. (Or just give the coders the honor of being test pilots. That will make those code monkeys program it real good the first time...)

Re:Where is their spirit of adventure? (0)

Anonymous Coward | about 2 years ago | (#39781365)

You may be joking, but you have a valid point. What penalties do "software engineers" have if they screw up? Do they lose their professional license? Oh wait, they don't have professional licenses like real Engineers have to get.

Re:Where is their spirit of adventure? (0)

Anonymous Coward | about 2 years ago | (#39782745)

I'm assuming that they have basically the same penalties as most other workers: if they screw up something sufficiently important they either get shown the door for it or are working for a company whose HR incompetence dooms them to a string of failures, which isn't necessarily the most stable choice of employment...

I'm unconvinced by the 'professional licensure' or, more broadly, blame-the-bad-coders school of argument. Are there bad coders? Sure. Negligent ones? Sure. However, is there much incentive in the industry to actually produce high quality products? Not really. Given the choice, almost everyone who doesn't have the FDA, FAA, or the like breathing down their neck seems to chose fast, cheap, and lots of features over quality first, speed and cost second.

Under those conditions, even good programmers are likely to be under instruction to use their talents to deliver fast rather than flawless. Unless one changes the customer demand, putting the peons between a boss and a licensing board is merely mean rather than helpful...

Re:Where is their spirit of adventure? (1)

HangingChad (677530) | about 2 years ago | (#39781585)

Cowards!!! Launch early, launch often.

Seriously, if the rocket went wonky the most likely place for it to land would be on Titusville. Whatever it hit there would make an instant improvement.

Re:Where is their spirit of adventure? (1)

t4ng* (1092951) | about 2 years ago | (#39782821)

Exactly this. It will be interesting to see how the "ship the beta, we'll fix it later with patches" style of development holds up in any renewed interest in space travel. So far it's not looking good.

Re:Where is their spirit of adventure? (1)

fuzzyfuzzyfungus (1223518) | about 2 years ago | (#39783163)

You wouldn't want to take it to the extremes commonly practiced by the software industry; but it wouldn't entirely surprise me if the 'ship now, fix later' model, within limits, actually holds up pretty well as long as only robots and expendable people(and no radioisotopic generators) are involved...

If space travel is going to be anything but a toy(outside of a few commercially viable niches for small satellites doing very valuable things in earth orbit), launch costs need to fall. If launch costs fall, the economics of being a raging perfectionist about every bit of gear you send up start looking less sensible compared to taking the risk of possibly having to send up a second one.

Concerns about space junk ruining valuable orbital slots will place a lower bound on how careless the world's nation states will let you be, and public opinion will be touchy about any accidents involving radioactive sources or high-profile humans burning up in the atmosphere; but nobody cares about the occasional satellite dropping dead or unmanned satellite launch blowing up...

Re:Where is their spirit of adventure? (1)

Darinbob (1142669) | about 2 years ago | (#39784705)

Well there's a wall full of post-it notes that will get them halfway there. Next week the scrum starts to get them the other half of the way.

Frustration (0)

Anonymous Coward | about 2 years ago | (#39780881)

I know this mission critical for SpaceX, but i hope they're not over doing it. It worries me when folks keep doing things at last minute. They had month delay, there going be growing doubt about them if they keep delaying like this. I can only hope for the best. *sigh*

Did they try... (1, Funny)

Troyusrex (2446430) | about 2 years ago | (#39780903)

updating to the latest version and rebooting? That's what vendors always tell us to do the second anything doesn't work perfectly.

Re:Did they try... (0)

Anonymous Coward | about 2 years ago | (#39780977)

"did you try turning it off and on again? Yeah, no problem."

Re:Did they try... (1)

Loadmaster (720754) | about 2 years ago | (#39781599)

Here's the transcript from the launchpad.

Robot #2: "Uh oh, he froze up again."
Robot #3: "Try control, alt, delete!"
Robot #4: "Jiggle the cord!"
Robot #5: "Turn him off and on!"
Robot #6: "Clean the gunk out of the mouse!"
Fry: "Call technical support!"
Robot #2: "Ok, ok, he's back online."

NASA behind this (2, Interesting)

Anonymous Coward | about 2 years ago | (#39780979)

Not that SpaceX is infallible - but I think it's NASA behind this requiring an insane amount of testing. They employ the Monte Carlo method of testing which basically tests every (or at least a random sample) value of each input variable and the combinations there of. I don't care who you are, but that method of testing is going to result in "issues" coming to the surface. The problem is that the issues will be extremely rare if not practically impossible. And Musk is not in a position to criticize them, since he wants their business for cargo and crew services.

Not saying this kind of testing isn't valuable, but it doesn't lend itself well to schedules.

Re:NASA behind this (4, Insightful)

mbone (558574) | about 2 years ago | (#39781079)

Space travel has a long history of "extremely rare if not practically impossible" issues coming up to bite you. Missions have been lost because of a single missing comma in the code. So, there is reason for this caution, and neither you nor Elon Musk is going to be able to change it.

Re:NASA behind this (0)

Anonymous Coward | about 2 years ago | (#39781259)

Agreed. Every accident is a rare combination of variables coming together, and Monte Carlo is good at catching that - whereas traditional testing (throw use cases at it) is not. It comes down to your level of risk that you are willing to assume. What I think is going on is NASA is placing a zero risk policy on SpaceX so everything that comes up is having to be dealt with. When you look at some of the things that NASA has done - it is easy to see that they don't hold themselves to this same standard. But this is a contractor relationship, and frankly, there are a lot of people within NASA that don't want SpaceX to succeed or at least would want them embarrassed.

Re:NASA behind this (2)

taiwanjohn (103839) | about 2 years ago | (#39781105)

Can't say I blame them for all the testing, given the potential risks involved. It's frustrating as hell to put up with the delays, but we space geeks ought to be used to that by now.

One thing I'm curious about is whether or not they're going to try recovering the booster stages on this launch. Musk has said in the past that they're going to "keep trying until we get it right," but with all they've got riding on this mission already, I wouldn't be surprised if they skip that in order to concentrate everything on rendezvous and berthing. Still, it would be quite a feat if they could pull off that stunt as well on this launch.

Re:NASA behind this (0)

Anonymous Coward | about 2 years ago | (#39781293)

SpaceX was trying to recover the first stage but I believe they have given up on the practicality of a ballistic, parachute assisted recovery. They are concentrating on development of a powered decent of the first stage. But this is nowhere near ready.

Re:NASA behind this (3, Insightful)

luis_a_espinal (1810296) | about 2 years ago | (#39781333)

Not that SpaceX is infallible - but I think it's NASA behind this requiring an insane amount of testing. They employ the Monte Carlo method of testing which basically tests every (or at least a random sample) value of each input variable and the combinations there of. I don't care who you are, but that method of testing is going to result in "issues" coming to the surface. The problem is that the issues will be extremely rare if not practically impossible. And Musk is not in a position to criticize them, since he wants their business for cargo and crew services.

Not saying this kind of testing isn't valuable, but it doesn't lend itself well to schedules.

This is how you test mission critical systems. No, this is how you must test mission critical systems, regardless of schedules. The key adjective here is "mission critical". This ain't a Heroku web deployment just so you know.

Re:NASA behind this (0)

Anonymous Coward | about 2 years ago | (#39782301)

Don't disagree this is how you test mission critical systems. But the nature of this kind of testing is to find plausible failure scenarios - not necessarily to be a go/no go decision maker. At some point you assume risk. The question is what level of risk is acceptable to NASA. It has to be low when dealing with the ISS. But I think what is going on is they are demanding 0 risk. In other words, demanding that the software is perfect enough to berth 1000 times with not a single anomaly.

I don't know what is really going on, but I suspect from side comments in interviews that this might be happening. Or maybe the Dragon app is crashing intermittently - that would be a good reason to hold the mission.

I base it on the following:

There was an interview with Musk at one point where he claimed that the Dragon software didn't have any bugs in it. Of course what he probably meant was known bugs. But this is before the code was submitted to NASA for their Monte Carlo testing.

Every time their is a date set for launch NASA has always said "pending testing results" -- even the press conference held a few days ago. So testing has been ongoing by NASA since mid last year!

A off hand comment by Musk when asked about the delay stating that they are making changes to deal with scenarios however unlikely they may be to occur.

Life support systems require more rigorous testing (5, Insightful)

tlambert (566799) | about 2 years ago | (#39781657)

Life support systems require more rigorous testing than simple Monte Carlo. They generally require component testing, bounds case testing, and branch path analysis of the code so that every line of code gets hit during testing.

I've worked on two projects that qualified as life support systems; one was an MRI console for a GE Medical Systems MRI machine (back when it was still being called NMR before it was politically corrected to remove the word "Nuclear"), and the second was a blood gas analyzer. Incorrect operation of the code in either of those cases could have resulted in someone dying as a result of a doctor getting misinformation.

The amount of testing and the rigor of the testing involved in both of those projects was unbelievable. Even then, we were required to carry liability insurance out the wazoo on both projects in case we screwed up the code. There's a reason medical equipment is so expensive.

Space systems that can ram into an occupied space station, and which are intended to some day carry humans to orbit qualify as life support, even if they are being sent up with a load of supplies instead of a human crew. Monte Carlo won't cut it any more than it will for a system call fuzzer trying to find a sequence of three system calls in a row that , if they are called with precisely the right parameters, will trigger a kernel panic.

-- Terry

Re:NASA behind this (4, Insightful)

crazyjj (2598719) | about 2 years ago | (#39781743)

NASA and Russia are extremely cautious when it comes to anything ISS-related for very good reason. If this thing really screwed up and seriously damaged ISS to the point where they had to abandon it, it would probably end the era of human spaceflight and lead to big budget cuts for both agencies.

I can see the headlines now (2)

crazyjj (2598719) | about 2 years ago | (#39780995)

"ISS Seriously Damaged Because That Fucking Moron Peter Forgot To Do Garbage Collection."

Re:I can see the headlines now (1)

Megane (129182) | about 2 years ago | (#39781021)

Next week on Family Guy: Peter gets a job writing spacecraft docking software!

Re:I can see the headlines now (0)

Anonymous Coward | about 2 years ago | (#39781065)

"ISS Seriously Damaged Because That Fucking Moron Peter Forgot To Do Garbage Collection."

Nitpick: isn't the point of garbage collection that it's done automatically (versus "memory management" for GC-less runtimes)?

Re:I can see the headlines now (0)

Anonymous Coward | about 2 years ago | (#39785729)

Put that dang nit back where you found it! Everyone knows GC only automatically happens at the worst possible moment.

Ported Code (0)

Anonymous Coward | about 2 years ago | (#39781035)

Maybe they realised that porting bump mapping was not going to cut it when it went from virtual to real.

Wait, what? (1)

tgd (2822) | about 2 years ago | (#39781133)

How does a statement that they're doing "more testing" turn into "fixing bugs"?

All the posts on here are all ZOMG, buuuug fixes!

The tweet and article say no such thing. And if you haven't finished your test cycle, best to delay and finish it. That's not rocket science.... or is it?

Re:Wait, what? (1)

FatLittleMonkey (1341387) | about 2 years ago | (#39801859)

Rumours are that they've been getting too many erroneous abort codes during testing. It may not be true, but it seems a reasonable inference that solving such a problem would have required changes to the code, changes that themselves required testing. Hence the delay.

One week? (1)

hey_popey (1285712) | about 2 years ago | (#39781271)

I am surprised. I don't remember very well what were the launch windows for LEO orbits, so this might not be applicable... But for GTO orbits, it was either one or two days of delay if there was a minor preparation glitch on the launcher, or something like one month if a new flight software had to be generated and qualified... Anyone knows more about this?

Re:One week? (1)

BZWingZero (1119881) | about 2 years ago | (#39784007)

For the ISS, launch windows are less than 10 minutes with about one window every day. This lasts a few weeks then there's a couple week period without a window.

if it were open source (4, Funny)

nimbius (983462) | about 2 years ago | (#39781283)

im sure you'd see git comments like
--removed sound-activated LED code
restored sound activation code. needed for espresso.py

--removed callbacks, class for rancilio espresso maker. please stop this.
--added pizza ordering support for dominos, stub for pizza hut

--removed food related code for pizza, chinese food, references to 'the luther'.
-- removed orbital re-entry positioning code. two can play this game
-- re-added orbital code. this is not funny. please stop.
-- added DMX512 dance-floor lighting control module, arduino support for twitter potted plant control

New iPad to launch from? (0)

Anonymous Coward | about 2 years ago | (#39781465)

Are they holding back because of the release of a new iPad is coming?

Launch window (1)

Skylax (1129403) | about 2 years ago | (#39781485)

Can he just delay by one week? There are only small launch windows for Cape Canaveral launches to ISS. Does somebody know the approximate window size for a Falcon 9+Dragon launch to ISS? Also from this [seds.org] ISS launch schedule, there is a launch of a soyuz at may 15th so if he delays too much, he will probably have to move the launch date back by at least a month.

I wonder what the requirements are at NASA versus SpaceX concerning mission failure probabilities? Reaching a 90% chance of success is probably easy but 99.99% chance of success is much harder.
And then you could ask if NASA or SpaceX has such high requirements why didn't SpaceX plan accordingly? Are they forced to promise early launch dates to keep investors?

Re:Launch window (1)

Anonymous Coward | about 2 years ago | (#39781787)

A launch window happens approximately once per day, give or take a few minutes.

The ISS has a fairly static orbit as far as it matters for this purpose, so you only have to wait for the earth to rotate to the right angle under it. It reliably does that with every rotation.

However, it is important to note that you can't just casually put off a launch for anther day, because for every delay you have, you're going to need to calculate a new course for the rocket's guidance system and make sure you haven't fucked that job up. For a machine costing a decent fraction of a billion, you don't just slap in whatever numbers seem right and hope for the best.

Re:Launch window (1)

Mercano (826132) | about 2 years ago | (#39781789)

There was a Atlas V scheduled to go up on the 5th, but that's now bumped up to the 3rd. I read over at NASASpaceFlight [nasaspaceflight.com] that Falcon 9 has a launch window approximately every three days from the Cape to ISS. Spaceflightnow.com has a worldwide launch calender [spaceflightnow.com]; you can see how many times this flight has been delayed. It was originally scheduled for June 6th of last year, so it'll be just a day shy of 11 months behind schedule, if there aren't any further reschedules.

Re:Launch window (1)

ClayJar (126217) | about 2 years ago | (#39781815)

The Space Shuttle had a launch window of approximately plus or minus five minutes from in-plane, but for the Falcon 9/Dragon COTS-2/3 launch to ISS, they have an instantaneous launch window. From the comments on the COTS-1 webcast, it sounded as if Dragon flights to ISS would have instantaneous launch windows, but I have no data to know whether this is merely a constraint for the initial flights or a constraint for all future COTS/CRS launches.

For the April 30th window (which will not be used), there was also an instantaneous launch window on May 3rd (with the days between those two blocked by ISS orbital constraints, I believe -- SpaceX has additional requirements for the test launch and recovery than for an operational launch). The next set of instantaneous launch windows would be May 7th and May 10th (with the days between blocked), but the May 10th window would mean that in the event of an aborted docking, there would be only time for one additional attempt before Soyuz conflicts (which would push the Dragon docking beyond May 17th, which may or may not be possible depending on fuel constraints, which I am not privy to).

Regarding the failure probabilities, from last week's press conference, it sounded as if SpaceX is the primary driver of mission assurance for this flight, i.e. they want to be sure they have as many of their waterfowl properly queued as possible. A cynic might note that if they don't get it right this time, it costs NASA nothing and SpaceX the full cost of another attempt. Someone with a brighter outlook would likely just say that if *everyone* on earth were watching you (most hoping you'd succeed, some hoping you'd fail), you'd *really* want to double-check everything one last time.

Falcon-Dragon (0)

Anonymous Coward | about 2 years ago | (#39782057)

I hope it lifts off, stalls at a height of 6 feet, drops, KABOOM BABY!!!
Let's show those North Koreans we still still do the best fireworks in teh world.

Title is wrong, /. SOP (2)

paramour (110003) | about 2 years ago | (#39782143)

TFA says the delay is for hardware in the loop testing, not code tweaking.

One hopes normal end-to-end testing was done long before this, but given the costs and logistics of assembling the actual hardware this final phase of testing pretty much has to wait until shortly before launch.

I'm a developer and am pretty much in the camp of "if it complies and boots, ship it", but I appreciate the need for QA. When you're shooting a missile at a fragile target keeping a crew alive 200 miles above earth just maybe before you sign off on the launch you want to finish testing. It's the low delta-v docking code they're testing apparently, but docking coupling damage has happened in the past, and that or just a failure to dock would be kind of a big deal.

Tests, not tweaks! (4, Informative)

wjsteele (255130) | about 2 years ago | (#39782267)

No where in Elon's Tweet or in the referenced article does it say they need to tweak the code... it says they need more time to "test" it.

Bill

Re:Tests, not tweaks! (1)

joh (27088) | about 2 years ago | (#39785737)

If the testing wouldn't carry the risk of having to change some code (or tweak some parameters) they could just stop testing and launch already.

Problem was just discovered. (0)

Anonymous Coward | about 2 years ago | (#39782947)

Since they are using Linux as the OS, there are no drivers available for the dock mechanism!!! Still waiting on a Sourceforge project to be created.

On a rocket? (1)

garyoa1 (2067072) | about 2 years ago | (#39783425)

What am I missing? I thot the commercial companies were all building a "kind of" plane or space ship since they'd be re-useable. Why/when did they fall back to rockets?

Re:On a rocket? (1)

wjsteele (255130) | about 2 years ago | (#39792831)

Actually, only a few companies working on non-orbital vehicles are designing aircraft with wings... since they spend a lot of their time in the air... in space, you don't need wings. It's much more efficient to design a vehicle without them if all you're doing is shooting it up on a rocket and landing it under a parachute (after reentry, which also causes problems for wings.)

Bill

Delayed because of code change or because .... (0)

Anonymous Coward | about 2 years ago | (#39790543)

.... because SpaceX CAN'T DELIVER ??

Sorry to burst bubbles, but SpaceX has a 90% rate of FAILURE. Even the flights where they claimed success were partial failures. On the last flight, the Dragon capsule CRASH LANDED in the ocean because the re-entry system failed miserably to activate. Out of 10 flights, only ONE made it to space (although not the target orbit).

I was excited about SpaceX, we need to commercialize space and their ideas sounded like a good start. But after watching how they lie and claim success on obvious failures I'm not going to give them any slack. Space flight is not a market where "it was good enough in my book so lets call it a success" is acceptable. The company can single handily destroy the future of commercial space by being IRRESPONSIBLE. They keep claiming that they can deliver, when it is more than obvious that they can not.

Re:Delayed because of code change or because .... (1)

wjsteele (255130) | about 2 years ago | (#39792881)

Really? I'm pretty sure Falcon 1 has successfully launced several payloads to orbit... which pretty much blows your assertations out of orbit. Also, the Falcon 9 has had launched twice, both successfully orbiting the Dragon capsule (though the first was just a shell with no avionics) it still was a successful mission. They did have failures (first 3 F1s for example) but that's not a 90% failure rate by any stretch.

Bill

ISS or Bust! (0)

Anonymous Coward | about 2 years ago | (#39794883)

kurtjmac is not going to be happy about this.
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