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Ariane 5 User’s Manual (2011) [pdf]
- cubefox 3y agoContext: Today is the last ever Ariane 5 launch.
- lagt_t 3y agoI understand there must be some irrefutably valid points, but it seems crazy since it launched the most expensive science experiment in a while just over a year ago, perfectly.
- WastingMyTime89 3y agoIt's not competitive with SpaceX anymore. The Falcon 9 is cheaper and is launched so often its track record is already comparable.
- malermeister 3y agoIt's not just about market competitiveness. It's also about keeping capabilities in Europe and not being fully dependent on a foreign entity with questionable leadership.
- kjs3 3y ago[flagged]
- malermeister 3y agoNever said anything to the the contrary, no need to be so confrontational.
- WastingMyTime89 3y agoYes but you don’t need two launchers for that, only the latest one. Countries financing its development will want to use as much as possible to bring the cost per launch down. As implied by the comment I’m replying to, the only reason to keep Ariane 5 flying would have been its good track record bringing business on the commercial market but that’s not going to happen because Falcon 9 gets all these customers now.
- sidewndr46 3y agorather ironically, I do not believe there is the possibility of launching the Ariane 5 from Europe.
- hef19898 3y agoThe French spaceport is, despite being close to the equator in latin america, part of the EU. And a rather good location.
- sidewndr46 3y agoI think the problem is in the event of war how do you manage to securely transport a launch vehicle and its payload to South America?
- malermeister 3y agoLooks like there's a space port in Sweden now, too. Doesn't look like they're launching Arianes there yet tho. https://sscspace.com/the-world-watched-the-inauguration-of-spaceport-esrange/ https://sscspace.com/the-world-watched-the-inauguration-of-s...
- The_Colonel 3y agoThere are many scenarios other than war where you want independent launch capability.
- wongarsu 3y agoHow did the US supply Great Britain throughout WWII, and how did they manage to ship their equipment and personnel there to actively fight in the European Theater in the later years of the war? War is full of logistics challenges, and slipping a retrofitted container ship or tanker carrying an Ariane-sized rocket in between other innocent maritime traffic would be one of them. Though the more common scenario in the last century or so seem to be harsh words, boycotts and proxy wars, not total war and sea blockades.
- 3y ago
- rsynnott 3y agoWell, it's being replaced with the Ariane 6. The 4 was also fairly successful, but was replaced with the 5. It was actually meant to be retired a few years back.
- jackmott42 3y agoThe motivation for Ariane 6 is to halve launch costs and increase launch cadence. As some have noted though it will still be an order of magnitude slower cadence than SpaceX is achieving and still not re-usable at all.
- Gravityloss 3y agoSolids really make rapid reuse impossible. You need to recast them.
- dsq 3y agoI’ve been looking for something like this, thanks. I wonder if theres a similar manual (similar in that a non spcialist can follow and make some kind of sense from it) for SpaceX as well.
- icegreentea2 3y agoTry this? https://www.spacex.com/media/falcon-users-guide-2021-09.pdf https://www.spacex.com/media/falcon-users-guide-2021-09.pdf
- Sanzig 3y agoThere's also this guide for their rideshare (Transporter) missions, if you don't want to buy a whole rocket: https://storage.googleapis.com/rideshare-static/Rideshare_Payload_Users_Guide.pdf https://storage.googleapis.com/rideshare-static/Rideshare_Pa... It's surprisingly affordable, starts at $330k USD for a 50 kg microsat (although unless you want to build and qualify your own separation system, it'll really be almost double that because you'll have to buy a separation system from SpaceX).
- ExoticPearTree 3y ago"accessories not included" :))
- panick21_ 3y agoGiven that a dedicated rocket is gone run you 8 million or more, seems like a good deal.
- dsq 3y agoExcellent
- PreInternet01 3y agoFascinating, although especially the communications section shows the (2011) vintage: V24 circuits, pagers, and other miscellanea from a bygone era...
- bad_alloc 3y agoProbably something that works for them now and a change might degrade reliability.
- MrGilbert 3y agoI would have expected that the manual has way more pages and a bigger scope. I'm surprised it has "only" 270 pages.
- nunuvit 3y agoThe guide is just an overview to help potential customers ("users") decide if the Ariane 5 would work for their payload and mission. Nothing to do with Arianespace operating the rocket.
- rtkwe 3y agoI'd expect a detailed manual to fall under the Missile Technology Control Regime, MTCR, which is kind of the sister of ITAR for the EU.
- deleted 3y ago[deleted]
- nunuvit 3y agoThey wouldn't make a more detailed manual for customers that they couldn't show to those customers. They do provide more detailed interface and system documentation, but they don't share the restricted implementation details. Even for internal use, they'd want to confine the controlled information to a smaller subset of documents because otherwise it's difficult to circulate information.
- rtkwe 3y agoVery true. What I was saying was they probably couldn't provide what MrGilbert was maybe thinking this would because it would constitute restricted arms information. As neat as it would be to get some juicy details about the rocket even as it's being retired that info is very tightly regulated in most countries.
- nunuvit 3y ago
- DeathArrow 3y agoWhy was Ariane 5 retired? Did ESA replace it with something else?
- m2fkxy 3y agoAriane 6, which suffers from some delays. Vega and Vega-C are also supposed to fill the lower segment gap, but they are grounded after a series of mishaps. Tough spot for ESA launchers, but we'll get through this!
- semi-extrinsic 3y agoAFAIU only Vega-C is grounded, Vega is still in operations with SSMS 16 scheduled for September? But yeah, Vega-C has been very unlucky with the nozzle throat insert on the second stage eroding away and failing, plus the general trouble with certain parts being made in Ukraine now during the war.
- m2fkxy 3y agoTrue! Vega did experience quite some trouble in the past too.
- cubefox 3y agoThey wanted to replace Ariane 5 in time with Ariane 6, but it got delayed a lot. Ariane 6 will be ready next year at the earliest.
- pfdietz 3y agoAnd Ariane 6 isn't competitive against SpaceX either. They've really screwed up.
- robin_reala 3y agoOnly in the sense that everyone isn’t competitive against SpaceX. They absolutely could have done better, but the role isn’t to produce the most price competitive launch, the role was securing Europe’s launch capability. If both could be done at the same time then that’s a win but it’s not the primary goal.
- kps 3y agoThis is on the event of the last Ariane 5 launch, but the first Ariane 5 launch failed due to software. The inertial reference system (SRI) was derived from Ariane 4. Since 5 was faster, a numeric conversion overflowed, which was not physically possible on 4. Since overflow was ‘impossible’, there was no explicit handling. Since the code was written in a ‘safe’ language (Ada), an ‘unsafe’ undefined result was impossible, so the module panicked. The SRI operation at that point was not actually required on the 5, but they had not wanted to make ‘unnecessary’ changes to disable it. Finally, the flight computer interpreted the SRI crash diagnostic data as flight data, and sent the rocket wildly off course. https://esamultimedia.esa.int/docs/esa-x-1819eng.pdf https://esamultimedia.esa.int/docs/esa-x-1819eng.pdf
- fermigier 3y agohttps://www.irisa.fr/pampa/EPEE/Ariane5.html https://www.irisa.fr/pampa/EPEE/Ariane5.html "The truly unacceptable part is the absence of any kind of precise specification associated with a reusable module."
- danvk 3y agoThis is fascinating. It reminds me of the infamous MCAS on the Boeing 737 MAX. A system was designed, implemented and rigorously tested to be used in a specific scenario. A decision was then made much later to use it in a very different scenario without any understanding of the consequences.
- TMWNN 3y agoAnother such case is Atari BASIC. Revision A has a bug that causes a crash. Revision B fixed the bug, but the fix was then erroneously applied to similar code elsewhere, causing the same crash much more often than in Revision A!
- orbital-decay 3y agoAlso notable as one of the few actual software-related failures in spaceflight. It's usually some other design flaw at fault, as software has relatively small complexity footprint.
- rcarmo 3y agoWell, _this_ at least, is rocket science.
- JakaJancar 3y agoI love how all the acronyms in the glossary are basically inverted English ones. - BAF - Final Assembly Building - Bâtiment d’Assemblage Final I knew about NATO/OTAN and such, but didn't know it's so universal. They also had fun with some of them: - PLANET - Payload Local Area Network - SHOGUN - SHOck Generation UNit
- weinzierl 3y agoIt's not in this manual, but I definitely remember the Ariane to have an "Anti Pogo Device" which kind of sounds anti-fun, in a funny way.
- kergonath 3y ago> I love how all the acronyms in the glossary are basically inverted English ones It's very common because the order of adjectives and nouns is most of the time reversed between English and French (and Romance languages in general; it's the same with Spanish and Portuguese for example), but English retains so much French and latin roots that the initials are often the same. Other examples include - IMF/FMI (international monetary fund/fonds monétaire international) - EU/UE (European Union/union européenne) - and before it EEC/CEE (European economic community/communauté économique européenne) - SARS/SRAS (severe acute respiratory syndrome/syndrome respiratoire aigu sévère) - HIV/VIH (human immunodeficiency virus/virus de l'immunodéficience humaine) And many others I am sure, that's just what I could think off the top of my head.
- 3y ago