Landing
That main stage landing still amazes me. It's been travelling at over 6000km/h and it can land itself on a boat within a couple of metres of its target.
Nice work!
The colossally delayed first flight of SpaceX's crew Dragon got underway this weekend and stands at the two-thirds successful mark after docking with the International Space Station (ISS). Lift off The launch, from the same launch pad that sent Apollo 9 into orbit almost exactly 50 years ago, occurred on schedule at 07:49 UTC …
Im looking forward to SpaceX's half century of first stage landings.
But for now I'll just say 35 frickin' times. Thats 35 times more than anyone else who was heading for orbit.
Including the neck hair raising double bubble of the Falcon Heavy twin boosters landing next to each other.
There is another Falcon heavy launch planned later this year. Wonder if they will go for the triple?
With that being the 35th landing and the 69th Falcon 9 launch, it has now reached the point of more than half the launches have had the first stage land again.
There are two Heavy launches planned for the imminent future, the first one for Arabsat 6A is due to be the next flight from LC-39A so needs the base of the TEL to be reconfigured. The second is a test flight for the US Air Force expected to fly 6 to 8 weeks after the first using the same set of three first stage cores.
They went for it the last time and almost pulled off all three.
What I find more impressive is that when landing back on a pad on Terra Firma, instead of one of the drone ships, is that the booster is in fact aiming into the sea, and only once the onboard computers have determined that it has sufficient control does it move sideways to line up on the pad. Hence why a recent failure due to stuck control fins "landed" in the ocean instead of blowing up spectacularly near the launch site.
> the Crew Dragon is currently just another way to get to and from the ISS (which will almost certainly be a home for fish at some point within the next 10 years)
So instead of throwing the ISS away, couldn't someone like SpaceX buy it? They have the capability to get there - probably at a lower cost than anyone else and with the honkin' great payload of the BFR, any refurb work would be a comparatively small "lift".
We are told that LEO is halfway to anywhere in the Solar System. So it would be quite handy for those with an intention to go to Mars, to have a staging post at the "halfway" point.
I believe the issue with continuing with the ISS is its running costs. It's getting on a bit and needs quite a bit of maintenance. I seem to recall that NASA, et al, have been touting around for commercial companies to take it on, but no-one wants to.
If you want an orbiting garage, then you'd probably be better off starting with something new.
The other issue is: Where is the fuel coming from? If it's coming from Earth, what are you saving by sending the fuel & vehicle up separately?
“The other issue is: Where is the fuel coming from? If it's coming from Earth, what are you saving by sending the fuel & vehicle up separately?”
If you send fuel and ship up separately you aren’t saving anything per se. But you are sending up two loads instead of one, so now you have twice as much up there and you can now go further. How about sending three loads of fuel up? Or ten? The sky isn’t the limit!
Yes. Cargo launches are inherently cheaper than manned flights so lots of simpler cargo launches then you build a space tug for the fuel and supplies and use the emptying vessels as stores for waste. The whole assembly can also be used as a radiation shield for the solar wind ... everyone's a winner. If you were really sneaky you could build the tanks with shields/chutes creating landers to make outside toilets on Mars or wherever - kill 3 birds with one stone. I know it works, I saw Matt Damon in a documentary about it on the tv ...
> I believe the issue with continuing with the ISS is its running costs
Yes. However, those costs are based on NASA's inefficient and wasteful rocketry costs. SpaceX can send stuff up at a fraction of what NASA spend.
The biggie seems to me to be the orbit. Since the ISS is essentially a russian vehicle, launched from Baikonur, the orbit is inclined at an angle from the KSC. So there is a significant problem with reaching it from a Florida launch. If SpaceX was to take over operations of the ISS, they'd probably want to launch from Kazakstan. Whether the USAians would be happy with that could be the deal-killer.
>The other issue is: Where is the fuel coming from? If it's coming from Earth, what are you saving by sending the fuel & vehicle up separately?
Mars is very far. You need a lot of provisions to get there, and Delta-V when you arrive. GTO is pretty much the halfway point to anywhere in the solar system in terms of Delta-V.
It makes sense to boost as much ship and supplies as you can on one rocket, and fuel on others. A fully fuelled ship that can lift off Earth, departing from orbit is just better.
Since the fuel ships are fully reusable and can make many flights, and the fuel is practically free, it can be much more economical that designing a vast ship that must launch its own weight as well as huge supplies of fuel from the ground. That excess fuel capacity from Earth liftoff isn't going to be helpful on the long journey.
"I believe the issue with continuing with the ISS is its running costs."
The bigger issue - as seen with MIR - is mould (or mold for the Websterites)
It's a sealed environment, you can't stop all spores getting up there and once something embeds itself into the insulation it's effectively impossible to remove/kill without endangering the crew too.
Some varieties eat plastics/metals, so eventually you have problems with hull integrity to worry about.
These organisms are TOUGH too. They've happily survived prolonged exposure to vacuum and high UV levels in lab tests. The higher radiation levels seem to drive faster evolution and selection for toughness.The upshot being that any long-term orbital hab stuff needs to make provision for disposal of either the entire thing after a couple of decades or disconnection/replacement of older modules without disturbing the overall structure.
No, no! The answer is obvious.
One of the launches drags a looong rope behind it. When it reaches the ISS, the waiting crew drag it in after it has been connected to an also suitable length hose, then just pump up the fuel that you need. Then for other commodities, like food, they could be shipped in small canisters in the same hose as the fuel.
icon> or it may be a reasonable idea. I was taking my cue from Arthur C. Clarke's "space elevator" concept.
<i.
So instead of throwing the ISS away, couldn't someone like SpaceX buy it? They have the capability to get there - probably at a lower cost than anyone else and with the honkin' great payload of the BFR, any refurb work would be a comparatively small "lift".</i>
Depends on how badly it's falling apart and projected maintenance costs, continued solar panel efficiency, etc. The thing is that if BFR/StarShip works, the ISS will be rendered totally obsolete.
The ISS has a pressurised volume of ~980m<superscript>3</superscript>.
SpaceX's BFR/StarShip will have a pressurised volume of 1000m<superscript>3</superscript>.
So SpaceX plan to be able to do in a single launch what the ISS Consortium took ~20 launches to do.
CrewDragon lifts 7 people at a time. StarShip is aiming at hundreds. They'll be operating at a totally different level - literally more than an order of magnitude.
You could just lob a single StarShip up and have the same working space.
If they wanted to, the $/kg on Cargo BFR would allow them to build their own Space Station with many thousands of cubic metres of pressurised volume in just a couple of launches to get the big stuff up, then judicious use of Bigelow/expandable habitat spaces that will make the ISS look decidedly pokey and expensive for what it does.
maybe torus and ring .. tether and lunavator ... we can do it all .. but decisions and finances are under lock ... huh ... we have to disrupt it over crypto industry and de-centralization .. you imagine modestly ... i am on chasing mars anywhere in its orbit ... thanks ... bye reply
IIRC, the ISS needs constant maintenance, so you can't leave it unmanned for long periods. This was a cause of recent concern as a failed supply mission raised the possibility that the crew might have to abandon the station if a new cargo didn't arrive in time.
So if what you need is a Big Garage in the Sky with no crew on it, the ISS is probably not your best choice.
If re-entry fails it will be the only time Ripley has died - ok, I accept she was only a few cells at one point. She's almost immortal, perhaps the name was hopefully a good luck charm whereas a dead cuddly thing is bad publicity? That assumes Ripley doesn't have a stowaway ...
For a while his Twitter profile had a photo of him in a dinner jacket and a fluffy white cat on his lap, ala Blofeld. He also had a photo of the time the CRS mission underwent a RUD (or as the author beautifully put it, when falcon went foom).
Both show a certain sense of humour, but I stopped following him after he went a bit nuts with the paedo submarine debacle. It might be with hung a look if he's settled down a bit now.
You are not alone. I thought Fish In Space - Cool! Then I thought but how will the fish no which way is up? I even got as far as thinking about the difficulties of launching large volumes of water into space (presumably also a very real problem faced by aquatic aliens) and then onto how fiddly it would be to make a space suit for octopus when I realised my mistake.
It's a way to get to anything in LEO - at the moment the ISS is the only reasonable destination, but with the IDA likely to be reused there is no reason that future stations - whether military, scientific or commercial, shouldn't be able to use the dragon.
The concept of doing Apollo style take off/ return at the "Earth end" of any voyage does have some benefits.
One of the coolest things was showing the hatch opening with two views side-by-side. They had the view from ISS on one side, and the view from inside the capsule on the other.
That's the first time they've done that.
Also, it was strange how SpaceX sort of took over the NASA TV channel. Most of the show was done by SpaceX employees, and they even had the SpaceX jazz during pauses, which was unusual, as the NASA channel doesn't "do" music of any kind.
The biggest disadvantage of Falcon Heavy for deep space missions is that it's upper stage isn't rated for deep space missions and doesn't use a store-able propellant. FH would have to be modified to use a MethaLox upper stage or a redesigned payload fair to accept a third stage for true deep space mission. On top of that it's unlikely FH will ever be man-rated.
Can't you just use empty washing up bottles?
"You'll need a washing up bottle, but make sure it's empty first so check with whoever does the washing up. You'll also need a pair of scissors with a sharp point, so you'll might need to ask for help."
https://www.bbc.co.uk/cbbc/joinin/bp-post-of-the-week-rocket
The problem would be finding a budget to maintain it in its new use. As long as it's being maintained that money isn't available to spend on other projects. A commercial customer taking it over instead of destroying it would be perfectly acceptable, but it's just not a very commercially useful structure.
The article states:
"the Crew Dragon [2] is currently just another way to get to and from the ISS (which will almost certainly be a home for fish at some point within the next 10 years). Going further afield requires NASA's Orion capsule, which is still a year or so away from its first SLS flight."
Then again, you could say that the Mercury spacecraft (at the time of its first manned mission in 1958) was just another way to lob a man up high and bring him back down again. But it was the first big step in a development programme which led to the Apollo spacecraft that ferried Neil, Buzz, and Michael to lunar orbit a mere 11 years later.
SpaceX is currently working on flying two Starship "test articles" this year - you know, non-space-going versions of its planned beyond-LEO crewed spacecraft. Yes, that puts it currently behind the Orion test and development schedule: the first space flight of an Orion test craft was on 5th December 2014, but would you bet against SpaceX's schedule being able to catch up with Boeing and friends? - especially since the next space flight planned for Orion is in mid-2020.
To me, it looks like SpaceX has just flown a crew-capable spacecraft on a test mission as part of a development programme leading to the craft's use in the near future by a paying customer on missions that are pretty certainly going to happen, and that's great. And it's working on developing a spacecraft for beyond LEO work too.
In the meantime, the SLS hasn't flown with (or without) the Orion spacecraft. They're both still under development, as is SpaceX's Starship/Super Heavy spacecraft/launcher combination (formerly known as the BFR system), which last time I looked is intended to be able to out-do the planned performance of the SLS/Orion combination.
Crew Dragon 2 is operational, if not fully evaluated. The Orion MPCV and Starship are works in progress. Different types of creature entirely.
It's like this: SpaceX is proving its currently operational second generation orbital spacecraft while developing a beyond-LEO capable spacecraft and launch system. The "usual suspects" are working on something similar, only they're revamping old technology in their attempt to get the SLS and Orion combination operational - okay, calling Orion "old tech" is quite unfair (the shape might have come from the 1960s, but I bet very little else has), but the SLS certainly is old hat, what with those solid fuel engines straight from the 1970s. I don't doubt that the SLS/Orion setup will work well. What I'm not so sure about is that it'll ever see serious use, not if SpaceX's plans come off. If nothing else, SpaceX has shown that it can put things into orbit a good deal cheaper than the competition.
"You pick out the SRBs as old tech and ignore the shuttle engines?"
Well, the RS-25 Shuttle main engines in original form are still pretty good and, importantly, never actually exploded in use. From where I'm sat, solid fuel launch engines are never going to be a great idea for crewed space flight. You can't turn them off, for one thing - not solid fuel *launch* engines.
In any case, from the point of view of Shuttle-derived solid fuel engines, it's not really the number of joints that matters: it's how they're sealed from the point of view of avoiding a repeat calamity. If you've got reliably sealed joints, you're okay. If they're not reliably sealed, having just one joint is a serious risk.
I gather they're planning on eventually using cheaper, simplified, disposable versions of the RS-25 for the SLS in the long run, once they've used up stocks of the full-fat RS-25. It's a bit sad really: the RS-25 is a fine design which has proven itself reliable and re-usable, if not particularly cheap, but to degrade the thing and turn it into a throw-away part seems - I don't know, contemptuous? I'd say it's certainly contemptuous of the original hope for their original intended application: cheap, reliable, and re-usable access to LEO. The full Space Transport System failed to live up to its hope and its hype, but those RS-25 engines are hard to fault in many ways.
Meanwhile, Wikipedia says that they've already spent nearly US$14 billion of government funding on the SLS from its inception in 2011 without having flown anything yet. SpaceX is developing Starship/Super Heavy using nothing more than company earnings.
I don't buy the idea that "commercial" is always better than "tax funded" - who wants a commercially run police force? (yes I've seen Robocop)
But:
Place your bets, ladies and gents: which one's going to be in use a decade from now? SLS or Super Heavy?
The RS-25 was only sort of reusable -- they had to inspect it after each launch, and I think at least for a while they were fully rebuilding all the turbopumps. So the cost-benefit analysis of keeping it reusable is not entirely clear. The overall cycle cost of the Shuttle turned out to be inferior to non-reusable systems overall, although that's partly due to design decisions forced by military needs.
This kind of thing is truly inspirational - countries putting side their differences and working together to advance science and soft toys. But, as has been pointed out, the ISS is getting a little old so maybe it's time for a new ISS. Maybe this time something a little more...ambitious:
https://www.kickstarter.com/projects/gnut/kickstarter-open-source-death-star
"The Dragon capsule still needs to undock from the IIS. If it can't undock then that's a big problem for the proposed passenger flight. So I'd say the job is less than two thirds done."
Hmm. I'd say that once you've shown you can dock on autopilot, undocking is pretty much certain to come off without a hitch. It's a hugely easier job.
Certainly something could go wrong - it's complicated and tricky stuff, this space engineering. But most of the next steps are old-hat and relatively low-risk: decouple, jet away carefully to a safe distance, manoeuvre the craft to re-enter.
I'd bet quite a lot that those steps will all work without a hitch. It's the actual re-entry and splash-down, with a geometry and heat shield not yet proven in service - that's the really high risk bit.
We'll soon see if it works.