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SpaceX update: The engine did not explode
- lutusp 14y ago> SpaceX update: The engine did not explode No, it just became a "Falcon 8" while enroute. All joking aside, as a former NASA Space Shuttle engineer I'm very impressed by this private-enterprise venture into heavy-lift launch services. People have often speculated about how much cheaper launch services might be if they were in the private sector -- now we can find out. The preliminary signs are very good.
- kmfrk 14y agoThis is Paul (fucking) Lutus for people who might just miss the username.
- tar 14y agohttp://en.wikipedia.org/wiki/Paul_Lutus http://en.wikipedia.org/wiki/Paul_Lutus
- skeletonjelly 14y agoAnd also: http://www.reddit.com/r/IAmA/comments/9xgnd/iama_little_difficult_to_describe_designed_part/ http://www.reddit.com/r/IAmA/comments/9xgnd/iama_little_diff... http://www.reddit.com/r/IAmA/comments/q9qzn/iama_former_nasa_space_shuttle_engineer_created/ http://www.reddit.com/r/IAmA/comments/q9qzn/iama_former_nasa...
- luke_s 14y agoFor those who don't know who Paul Lutus is: http://en.wikipedia.org/wiki/Paul_Lutus http://en.wikipedia.org/wiki/Paul_Lutus Some key parts: "Lutus designed electronics for the NASA Space Shuttle and created a mathematical model of the solar system that was used by the Jet Propulsion Laboratory during the Viking Mars mission" and then "... he started writing computer programs on his first personal computer, an Apple II. In the 80s, he would eventually program Apple Writer," I also recommend his book about sailing around the world "Confessions of a Long-Distance Sailor"!
- ryanmolden 14y agoAnother great book about the same topic (sailing around the world), albeit written in a slightly different time: http://en.wikipedia.org/wiki/Sailing_Alone_Around_the_World http://en.wikipedia.org/wiki/Sailing_Alone_Around_the_World
- krakensden 14y agoAnd a third, with a slightly different ending, that may serve as a signpost to geeks with a predilection to romanticize working alone: The Strange Last Voyage of Donald Crowhurst (http://www.amazon.com/Strange-Last-Voyage-Donald-Crowhurst/dp/0071414290 http://www.amazon.com/Strange-Last-Voyage-Donald-Crowhurst/d...)
- tdonia 14y agoSame race, better outcome: http://books.google.com/books/about/The_Long_Way.html?id=rgKRmmMpJ8kC http://books.google.com/books/about/The_Long_Way.html?id=rgK...
- slackerIII 14y agoWow, thanks for pointing out that connection. I enjoyed reading that book years ago -- I recommend it for anyone with any interest in sailing.
- lutusp 14y ago> http://en.wikipedia.org/wiki/Sailing_Alone_Around_the_World http://en.wikipedia.org/wiki/Sailing_Alone_Around_the_World Yes, the Joshua Slocum book, a classic well worth reading. My book isn't in the same league, but it's developed a loyal following over the years -- it's online and free: http://arachnoid.com/sailbook http://arachnoid.com/sailbook My all-time favorite sailing book quote, from a book titled "Never Again", about a sail in the terrifying "South 40s" near Antarctica: "After the mast blew off, the boat become much more stable." :)
- waterlesscloud 14y ago
- stallker 14y agoWhy 'f*ing'? (Sorry, I'm italian... of course I know the meaning of the word, but I would like to know why do you use it for Paul Lutus, TIA)
- phaedrus 14y agoHey I think I met this guy. I was in Houston for a NASA internship, he had a telescope set up in front of a Barnes & Noble, and he was introducing random passers by to a view of Jupiter (or Saturn) in the telescope.
- nitrogen 14y agoResponding to a dead comment by stallker: stallker 4 hours ago | link [dead] Why 'f * ing'? (Sorry, I'm italian... of course I know the meaning of the word, but I would like to know why do you use it for Paul Lutus, TIA) I'm not the OP, but in some circles the four-letter expletive is used to emphasize the importance or intensity of something. E.g. "William [freaking] Shatner" means the original, unique, William Shatner, not some other William Shatner. "So [freaking] good!" means extremely good.
- pasbesoin 14y agoStill use your Windows NTP utility, upon occasion. Thank you.
- majormajor 14y agoThat reminds me of a euphemism that I found delightful that I heard once while working for a space company... "achieving submerged geostationary orbit," I think it was.
- eridius 14y agoI assume this means "crashed into the ocean"?
- majormajor 14y agoYep. I feel like there was another word in the phrase as used by the engineer I heard it from, but I can't for the life of me remember what it was.
- jcheng 14y ago"Involuntary"? :)
- indiecore 14y agoMy favorite spaceflight euphemism is still "rapid unplanned disassembly".
- olex 14y agoAnother good one is "rocket undergoing rapid unplanned disassembly shortly after launch": http://i.imgur.com/lnuqG.jpg http://i.imgur.com/lnuqG.jpg
- sehugg 14y ago"Lithobraking" is a good one (litho = stone or rocky surface, braking = ... well, stopping suddenly)
- adastra 14y agoaka "hydro-synchronous orbit"
- derleth 14y ago
- toomuchtodo 14y agoNo, it just became a "Falcon 8" while enroute. DUDE, give them a break..... read next line Oh. OH! I have no business commenting on this subject.
- nkoren 14y agoYes, I need to retract my prior comment about the engine "exploding" [1]; the failure mode was much more benign, and the surround engines were never under threat. However, the nozzle was very clearly ejected following the shut-down, so for all intents and purposes, it became an ex-engine. And the Falcon didn't flinch. Impressive. Watching this private space stuff manifest is absolutely thrilling. I was tangentially involved in things way back in the early 90's, when the private space geeks were regarded as crackpots by the mainstream aerospace community, if indeed they were acknowledged at all. They certainly didn't have any money (aside from odd forays such as Andrew Beal's[2] and Gary Hudson's[3] abortive adventures), and often did come across as crackpots, but for the life of me it seemed like they had a valid point. To see those sort of folks finally succeed is just infinitely thrilling. [1] http://news.ycombinator.com/item?id=4625221 http://news.ycombinator.com/item?id=4625221 [2] http://en.wikipedia.org/wiki/Beal_Aerospace http://en.wikipedia.org/wiki/Beal_Aerospace [3] http://en.wikipedia.org/wiki/Rotary_Rocket http://en.wikipedia.org/wiki/Rotary_Rocket
- maaku 14y agoThe nozzle wasn't ejected; relief panels were as a precaution in case it did explode.
- wamatt 14y ago>I'm very impressed by this private-enterprise venture into heavy-lift launch services. The fact that an engine failed, should be viewed as a success, as it allowed for the validation of the fault tolerant design. It's not that one should never have failures, what matters is how they mitigate and adapt, in order to complete the mission.
- greglindahl 14y agoA successful test of the one-engine-out code! Given that they don't want to initiate this failure on purpose, it's handy that they had one so early.
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- deleted 14y ago[deleted]
- DaniFong 14y agoHi there, I read your IAmA where you had a reply to a message, now deleted, in which you must have been asked about aerial circumnavigation. You mentioned that you'd use a solar balloon, and that you merely would have to have a strategy for darkness. I've spent a fair amount of time thinking about this, and it may interest you to know that: Water vapor has both a lower molar density than air The phase transition of water vapor gives more than enough energy to heat up more than the equivalent volume of air to displace the reduced volume of water vapor turning to liquid. So, a possible strategy for darkness is to have a two bladdered balloon, one with water vapor + air, one with just air. Then, when the water vapor condenses, transfer the heat to air sourced from outside the balloon via a counterflow heat exchanger. Put that warmed air in the air bladder. You won't stay at precisely the same height, but you will retain volume and you can stay buoyant. Many things work well when your thermal energy storage is positively buoyant. Regards, Come visit the next time you're free around Berkeley or Oakland.
- lutusp 14y agoThis is an interesting altitude-control scheme. When I think about this problem, I consider a method that involves a flexible helium container (in the simplest form, a helium balloon) and a control system that involves pumping helium out of the balloon into a high-pressure tank to descend, and releasing it from the tank to the balloon to rise. It's a variation on the submarine buoyancy method, which also requires power to run pumps. The advantage is that the method doesn't just throw away the helium, it recycles it, but the recycling activity require a lot of power. And it's way complicated compared to your method.
- DaniFong 14y agoYup, and things stay around atmospheric pressure throughout. I intend to build it at some point. (There's a long list, obviously, but this is a keeper) so if you're ever interested in it, let's chat. :-)
- davedx 14y agoHi Paul, Just a heads up - I tried to send a message to you on your website (arachnoid.com) and got the following error: Error: embedded tags. Warning: eregi() [function.eregi]: REG_EMPTY in /home/arachn5/public_html/messages/processMessage.php on line 84 Please press the "back" button to correct your entry. I don't have any HTML in my message, and I'd really like to send it :-) Do you have an email address I could use please?
- lutusp 14y ago> Do you have an email address I could use please? Yes, But for obvious reasons I don't want to post it in this forum. Please post a plain-text message to my message board and I will reply. Then you can embed links and tags in your reply if you want. That way neither of us needs to post our e-mail addresses in a public forum. Thanks!
- ghostfish 14y ago>"Panels designed to relieve pressure within the engine bay were ejected to protect the stage and other engines." Can anyone that knows something about the Falcon 9 design or rockets in general shed some light on this? That sentence makes it sound like the panels were purposefully jettisoned, which doesn't make sense to me. What do those panels do, what do they look like, and where are they?
- stephengillie 14y agoPurposefully jettisonning panels is a way of preventing an explosion from damaging the rest of the ship. The rocket creates energy in a direction, but what if something prevents the energy from going in that direction? The energy, in the form of expanding gasses, has to go somewhere. If these panels didn't break away to give the energy somewhere to go, it could have forced into another rocket or into the ship's body, causing a much bigger problem.
- jlgreco 14y agoSo are these panels kind of a sort of relief valve?
- maaku 14y agoThey serve a similar function, yes.
- luke_s 14y agoWhen they say "Jettisoned", it makes it sound like one of the flight computers decided to drop the panels. Wouldn't it more be the case that the panels are deliberately designed to be blown off? I have a hard time believing that any control system could react in time in case of an engine explosion...
- schiffern 14y agoThey said "ejected", not "jettisoned". You can be 'ejected' from a vehicle if you're not wearing your seatbelt, so the word doesn't require active response.
- rorrr 14y agoIf anything, this shows the fault tolerant design that works.
- biot 14y agoIt's essentially a RAID6 design for rocket engines.
- tomasquintero 14y agoRAID5, they can only sustain one failure.
- biot 14y agoIncorrect. From the fine article (SpaceX's release): "It is worth noting that Falcon 9 shuts down two of its engines to limit acceleration to 5 g's even on a fully nominal flight. The rocket could therefore have lost another engine and still completed its mission."
- btilly 14y agoI was curious about how reliable we should predict a Falcon 9 launch to be based on the stated design parameters (survives the loss of any 2 engines) and current launch data. I found that under a simple Bayesian model, the estimated probability of catastrophic failure during the next launch is 3.6%. See http://bentilly.blogspot.com/2012/10/how-reliable-will-falcon-9-be.html http://bentilly.blogspot.com/2012/10/how-reliable-will-falco... for details. Update: I made a careless calculation error. Change 3.6% to 2%. Oops.
- ghostfish 14y agoTwo thoughts here. 1) You're working from an awfully small sample, especially for a component that is supposed to be of such a high reliability. Then again, look at the probabilistic assessment of Shuttle success vs. actual. 2) The Merlin 1C engine is only going to make a few more flights afaik. Starting some time in 2013 they'll be switching to Merlin 1D.
- btilly 14y agoIndeed, predictions are extremely hard. Especially about the future. At least I am explicit in the assumptions behind that model. They are: 1. A priori, all possible reliability numbers for a single engine are assumed equally likely. (This can be debated endlessly, but you need SOME prior for Bayesian analysis. If we had more data, then the prior would matter a lot less, but we don't so it does.) 2. Failure of engines is independent. 3. The rocket actually operates according to design parameters. That is it will survive the loss of any 2 engines, but not the loss of 3. 4. Past performance is a predictor of future performance. Every one of those assumptions is questionable.
- pilom 14y agoUnfortunately #2 is extremely unlikely to be true. Engine failures are very related in very unexpected ways. The SpaceX guys have worked very hard to make them as independent as possible but with so many failure modes it is impossible to say that an engine failure (i.e. explosion) will have no impact on its neighbors.
- molecule 14y agofollowing the Engine-1 failure, did Falcon 9 continue w/ six engines operating, or was one of the two previously shutdown engines re-engaged?
- HodCarrier 14y agoThe engine failed prior to MECO-1 (where the first two scheduled shutdowns occur) so there were still 8 lit engines. There's no capability to restart the engines that have been shut down.
- SoftwareMaven 14y agoI saw the engine flame out and the panels come apart during the launch. I expected some comment on the launch radio because it was obviously not SOP (engines shouldn go out with debris), yet, due to good design, the entire launch remained nominal. I am now getting hopeful that I'll be able to experience zero-G before I die. SpaceX team, you are my heroes. Keep up the great work!
- rst 14y agoThe main mission (Dragon/ISS) wasn't affected, but a secondary payload (an ORBComm test satellite) was left in the Dragon's insertion orbit, and didn't get the scheduled secondary boost --- apparently because, after the delayed orbital insertion, the reboost would have gone too close to ISS, according to an ORBComm press release: www.orbcomm.com/Collateral/Documents/English-US/ORBCOMM%20Launches%20Prototype%20OG2%20Satellite%20FINAL.pdf
- jakkals 14y agoAm I the only one who got confused by the first sentence? "The Dragon spacecraft is on its way to the International Space Station this morning and is performing nominally...". Is everything fine now, or is it not? "Nominally" in this sense to me means that something is amiss, but reading the rest of the article seems to imply that everything is on track.
- CUViper 14y agoI'm not sure where you get that sense of the word. Nominal = according to plan.
- dtparr 14y agoI see this confusion fairly often. Outside of the status of systems/missions etc., nominally often means something like 'in name only'. So to say it's proceeding 'nominally' to someone not familiar with its meaning in this domain sounds like "well, it's going according to 'plan', but ..."
- jakkals 14y agoHm. I have never heard that meaning of the word previously, and the link I previously provided (http://dictionary.reference.com/browse/nominal http://dictionary.reference.com/browse/nominal) also did not show that specific meaning (unless I am too blind to see it!). I do find it interesting though that you seem to think that it is commonly used in this sense, so I guess I am not moving in the right technical (aeronautics) circles :-) Thanks for the feedback.
- Sharlin 14y ago"Nominal" is the favorite word of aerospace engineers. Both in the sense that they like to use it a lot, and in the sense that they very much like to hear that things are going according to the plan.
- CUViper 14y agoHeh, no aerospace background for me, merely computer engineering. Maybe that's still close enough for the term to have crept around with that meaning. Now go forth and help spread this usage far and wide! ;)
- bravesirrobin 14y agoI have to admit that I'm impressed at how well the system they build compensated for the mechanical failure. It looks like they have some good people building things. One aspect that's worth consideration is the private/corporate aspects of spaceflight. When there were failures in Apollo and the shuttle, the public had a right to know everything that happened since we'd paid for everything. SpaceX has been super cool about disclosure here, but how long can we count on that? At some point, there's too much money at stake for them to maintain full transparency.
- wprice 14y agoWhat's more important than disclosure to the public after something has gone wrong, is disclosure to the customers (e.g. NASA) and future astronauts ahead of time if something has been identified as a potential problem before launch. The Space Shuttle Challenger disaster occurred because managers failed to acknowledge the warnings of engineers, who recommended postponing the launch due to cold weather which could prevent some O-rings from functioning properly. Having the ability to acknowledge and correct problems ahead of time, even if it means a launch delay and potentially some lost profits, will ultimately pave the path for a sustainable private space industry. But I think that SpaceX understands that NASA is funded by the public and it will be easier to get the support of NASA if they have the support of the public. I would suspect that for this reason they will continue a decent amount of public disclosure.
- knodi 14y agoI am speechless in amazement. So badass!!
- confluence 14y agoI saw the launch live and I saw the debris ejecting about 90 seconds in. What I found particularly amazing was that SpaceX either didn't know it, didn't want to confirm it or just realised that their design worked because all I heard after that was my favourite aerospace term "Situation nominal".
- maaku 14y agoSimple efficiency of communication. The guy saying “situation nominal” was the one looking at the engine data.
- dhughes 14y agoI bet the ISS crew yelled the ice cream noo!
- eupharis 14y ago"Falcon 9 did exactly what it was designed to do. Like the Saturn V (which experienced engine loss on two flights) and modern airliners, Falcon 9 is designed to handle an engine out situation and still complete its mission. No other rocket currently flying has this ability." Chills down my spine as I read this. I try to write eloquently, but sometimes the fact should stand alone: "No other rocket currently flying has this ability."
- rplnt 14y agoThis reminds me of a major feature Chrome had when launched - to withstand a crash of any of the opened tabs. I thought it's a funny feature to have... other browsers just preferred not to crash in the first place. Then I tried Chrome and realized it was a great feature for them, because Chrome kept crashing all the time (back then). What I wanted to say by this is that while it's a great thing for Falcon 9 to have fail-over in its maiden flights (as we could see yesterday), I wouldn't worry too much about "other rockets" not having this. Soyuz rockets are a great example (100% success rate for manned flights to ISS and over 97% success rate for all Soyuz rockets (that's since 1966)[1]). 1. my numbers are only from wiki: http://en.wikipedia.org/wiki/R-7_(rocket_family) http://en.wikipedia.org/wiki/R-7_(rocket_family) and http://en.wikipedia.org/wiki/List_of_Russian_manned_space_missions http://en.wikipedia.org/wiki/List_of_Russian_manned_space_mi...
- VSerge 14y agoIt's amazing that this could have worked as a Dragon 7. One engine failed and they still could have made it with one other engine malfunctioning. Bearing in mind the cost of the launches for SpaceX are forecasted to be significantly lower than old shuttles, this is all the more impressive. There was a misshap though, since the Orbcomm satellite wasn't nearly put on the right orbit. I have no idea whether the onboard propulsion of the satellite will be enough to get into the desired orbit, but if they do manage it, it will be a testament to the quality and interest of fault-tolerant space operations.