That seems a lot easier and cheaper. I'm tempted to think that maybe there's some factor that makes it more difficult to engineer a rocket that can handle sideways stresses as well as vertical stresses, but... heck, it's a rocket, they shouldn't be that fragile, should they?
The launch vehicles themselves may not be that fragile, but payloads often are. Multimillion-dollar satellites can be damaged or completely non-functional from effects as small as being dropped 1 meter (see http://www.spacetoday.net/Summary/2230 , for example).
If the bolts holding the payload in place shear away under the lateral force of supporting the payload, the payload may fall and hit the hard inside of the launch vehicle, making the two events quite similar. (Indeed, the original drop I linked to occurred when the satellite was not correctly bolted to a table on which is was going to be tipped to one side in order to verify that it could withstand the stress of being in that physical orientation.)
That said, ugh's comment suggests my reasoning (as an explanation for vertical assembly) is either incorrect, incomplete, or both.
Ariane rockets are also assembled vertically [1]. Since assembly and adding the payload are two discrete steps, done in two different buildings [2], both of the times vertically, that tells me that there is more to it than the payload.
The main reason is merely tradition (really). Most systems are designed as evolutions of older systems, if the first system used vertical assembly, then so will the latest.
Note that the Russians have been doing horizontal to vertical launch vehicle assembly for decades (with manned and unmanned launches). There's no engineering reason why you must prefer one method or the other, it's a choice.
This does indeed suggest that there may be other factors at work. I could try tossing out other ideas, but they would be little more than hypothesis. (Bending during the tipping process damaging the joints in multi-segment launch vehicles? This might explain the difference with SpaceX's Falcons, which I believe do not have joints with O-rings.)
IIRC Russian rockets are also taken lying down to the launch platform and are rotated into vertical position. You can see a couple pictures of that happening at
I did a bit more googling and Delta rockets are also built horizontally and raised. A Delta IV is bigger (or at least taller) than the space shuttle launch system, so size isn't the issue.
All over the world people believe all kinds of rubbish. But engineers look at things and say "I know how to do that" or "why don't you do this" - and you end up with stuff like this. Fantastic!
yeah, i was all proud of myself for hosting a new engine in my car last weekend and getting everything lined up and bolted together. Thought it was an impressive feat. Now, not so much.
I didn't have an engine puller so a friend helped me lift the engine out of my Spitfire to replace the clutch. When I put the engine back in another guy helped me and we almost dropped the engine and both got major back pain. I realized that friend 1 must have done 75% of the lifting. Next time: engine puller.
I always wondered if it would be possible to take the SSMEs out of the shuttle and mount it on top of a larger booster vehicle that could also be used to lift non-reusable craft.
A couple of SSME-class engines on the bottom of that tank, with two or four SRBs around it would make for a very serious launcher. BTW, that's the idea behind the Jupiter boosters the DIRECT folks were proposing.
IIRC Nasa seriously investigated building a vehicle like this, but found that SSMEs were way too expensive for use in a disposable rocket. There are other engines that will do the job and are much cheaper.
True. The SSMEs are more complex and expensive than disposable engines.
IIRC there is no large cargo vehicle in the current NASA plans. That's a bit sad. I won't be able to take my son to watch a shuttle launch and it's very likely he won't be able to take his kids to watch anything the same size.
I don't see much demand for launchers that large. While the LEO payload capacity of a shuttle is large, comparable to, say, a Delta IV Heavy or the largest (not yet flown, AFAIK) Angara, the total vehicle weight is much larger. A shuttle launch is equivalent of hauling 100 tons to LEO (30 of payload and 70 of shuttle).
And if anyone else was wondering, as I just was, why it's called a hangar, apparently it's from a word for "shed" in some dialect of French. The word itself is probably Germanic in origin.
And it has absolutely nothing to do with hanging, which makes sense because you don't hang things in a hangar anyway.
It’s from “Haim” and “gard”. “Haim” means basically house (and the word “Heim” for “Home” still exists in German) and “gard” means something like garden or protected area.
No need to be sorry. It was my screw up. I fixed on my post but I am not able (that I know of) to fix the Hacker News Submit. /Nit Pick away as it is my bad! Thanks.
Great time lapse movie. No, really great. Made my day.
But... It would have been even _better_ if it had used _The Blue Danube_ for background music. Especially as it was being hoisted on the crane.
Edit: I just tried this by finding a _Blue Danube_ movie on Youtube and playing it in the background while re-watching the movie. It should be a _crime_ not to try this. Some interesting serendipities in timing, especially involving violin solos and the cable top shot sequence.
[1] http://en.wikipedia.org/wiki/Vehicle_Assembly_Building