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SpaceX lands rocket at sea second time after satellite launch

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Re: SpaceX lands rocket at sea second time after satellite launch

#491

Post by lmm »

InclinedPlane wrote: post #490
lmm wrote: post #318

Earlier quoted context omitted.

Airliners don't land on their tails either. If that's your model then Adeline is the correct approach.

I think you missed the observation there. Airliners could certainly land with parachutes. They could even glide in for unpowered landings. And doing so would save a lot of fuel in either case. But that fuel savings would come at the cost of adding huge operational complexities, and risks. Powered landings are more precise, more predictable, and more reliable. They reduce operational complexities, even if they are cos…

I just don't think you can generalize like that. A "powered" landing for an aeroplane is very different from what SpaceX is doing, e.g. an aeroplane can and often does abort and go around, whereas the rocket has no such capability.

Re: SpaceX lands rocket at sea second time after satellite launch

#492

Post by InclinedPlane »

lmm wrote: post #491
InclinedPlane wrote: post #490

Earlier quoted context omitted.

I think you missed the observation there. Airliners could certainly land with parachutes. They could even glide in for unpowered landings. And doing so would save a lot of fuel in either case. But that fuel savings would come at the cost of adding huge operational complexities, and risks. Powered landings are more precise, more predictable, and more reliable. They reduce operational complexities, even if they are cos…

I just don't think you can generalize like that. A "powered" landing for an aeroplane is very different from what SpaceX is doing, e.g. an aeroplane can and often does abort and go around, whereas the rocket has no such capability.

Rocket landings are different than plane landings, but that doesn't mean powered landings are less worthwhile. In either case a powered landing means a more precise, more reliable, more repeatable situation. And if you want to maximize the operational lifetime of the equipment, that's what you want.

Re: SpaceX lands rocket at sea second time after satellite launch

#493

Post by gallonofmilk »

Kutta wrote: post #403
Inconel wrote: post #116

Earlier quoted context omitted.

I too find it hard to see how so many have conflated chanting for a group, in this case the USA, as being equivalent to actively admonishing another group. The employees at SpaceX aren't burning the flags of foreign countries or otherwise disrespecting or mocking them, they are simply expressing pride in the nation that many of us view as playing an instrumental part in our success. I also don't know what could be do…

You have given a fairly comprehensive explanation (here and in other comments) as to why it's unreasonable to be disturbed by the chanting and why it would be beneficial for SpaceX employees to be let chanting as they wish. I don't think is enough or appropriate. A significant fraction of global viewership is disturbed and alienated by the chants. It might well be that they're having the wrong feelings for wrong reas…

> A significant fraction of global viewership is disturbed and alienated by the chants.

What is your source? How can you be so sure? There is absolutely no factual evidence that anything other than a fraction of viewers with thin skin are being "disturbed" by what is a group of proud workers displaying their pride.

Re: SpaceX lands rocket at sea second time after satellite launch

#494

Post by _kst_ »

downandout wrote: post #54
kirrent wrote: post #7

For those wondering, this isn't a simple repeat of CRS8 which landed on a drone ship about a month ago. CRS8 was a mission to low earth orbit which left the first stage with plenty of fuel to effect a landing. The landing was made as slow as possible and limited only by how low a single engine could be throttled. The re-entry burn which slows the rocket down before the landing burn was also more agressive. This missi…

From the video it looks like it lands on a ship in rough seas and they do nothing to secure it. Won't it just fall over if the seas are rough enough, and if so, why don't they have some sort of robotic system that locks it down tight the moment it lands?

Apparently they do secure to the deck after landing.

Discussed here: http://space.stackexchange.com/q/6403/574

Re: SpaceX lands rocket at sea second time after satellite launch

#495

Post by odonnellryan »

lmm wrote: post #489
odonnellryan wrote: post #269

Earlier quoted context omitted.

This argument makes no sense.

The point is that SpaceX hasn't yet accomplished anything NASA didn't. That SpaceX's approach will be more suitable to future things is not a good counterargument.

They have: they're cheaper, they've developed new technologies, and they're doing it privately.

> That SpaceX's approach will be more suitable to future things is not a good counterargument.

No one is saying that, they're just being positive and looking forward to the future.

How is that bad?

Re: SpaceX lands rocket at sea second time after satellite launch

#496

Post by _kst_ »

rblatz wrote: post #437
_kst_ wrote: post #431

Earlier quoted context omitted.

Before it landed, the most likely scenario was that the rocket was going to crash into the deck and be destroyed. (That's happened several times before.) If they can deal with that, they can deal with the rocket landing safely and then falling over.

They can until it gets to a busy port with other ships and people around. Then it becomes a huge safety issue.

Copying my other comment:

Apparently they do secure to the deck after landing.

Discussed here: http://space.stackexchange.com/q/6403/574

Re: SpaceX lands rocket at sea second time after satellite launch

#497

Post by lmm »

odonnellryan wrote: post #495
lmm wrote: post #489

Earlier quoted context omitted.

The point is that SpaceX hasn't yet accomplished anything NASA didn't. That SpaceX's approach will be more suitable to future things is not a good counterargument.

They have: they're cheaper, they've developed new technologies, and they're doing it privately. > That SpaceX's approach will be more suitable to future things is not a good counterargument. No one is saying that, they're just being positive and looking forward to the future. How is that bad?

Doing things cheaper is good, sure. All I'm saying is that zupreme's original point is fair (they haven't (yet) really done anything concrete that NASA haven't (just done it cheaper), and the current enthusiasm is perhaps disproportionate)
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