Launch News SpaceX Falcon 9 launch with Jason-3, January 17, 2016

[Col_Klonk]

Did I mention it was too tall a stage for this type of landing. ?

Spot on landing... but why land on the barge when it's not proven yet, even with a smaller rocket.
There will probably be an insurance claim on this ??

 

[Urwumpe]

Spot on landing... but why land on the barge when it's not proven yet, even with a smaller rocket.

Force the Russians to design a 50 m long anti-ship missile for staying the country with the largest anti-ship cruise missiles? :lol:

 

[ADSWNJ]

Did I mention it was too tall a stage for this type of landing. ?

Spot on landing... but why land on the barge when it's not proven yet, even with a smaller rocket.
There will probably be an insurance claim on this ??

What are you talking about? Too tall? It's already proven that it can land this tall a rocket on land. Why land on a barge? So it can be recovered when the dV demands eliminate the possibility of a return to a ground based landing site.

No insurance claim needed, as this is their engineering testing, with a high chance of failure. The alternative is to drop it in the sea anyway, for a guaranteed loss. So your comments make no sense.

---------- Post added at 04:44 PM ---------- Previous post was at 04:40 PM ----------

Damn, they did stick that landing.
They have to do something about those legs. All four legs have to work. They hit me as being the least robust components on the entire rocket and have no backup.

They already have (on the upgraded version).

In the reddit/com/r/spacex subreddit, there's discussion of whether 5 legs would be preferable, as you could design it to be stable with 1 leg failed, or potentially even 2 legs out if not next to each other.

The better solution though is probably better shock absorbers and latching. That's the cool thing about SpaceX ... this one fails, and the next one will already by flying a modified component. Rapid development cycle, driving enhancements in a timeframe rarely seen on space hardware.

 

[Donamy]

Even if it did land, a good wave probably would have tipped it over.

 

[Urwumpe]

Rapid development cycle, driving enhancements in a timeframe rarely seen on space hardware.

Yes, but it is doubtful that this development model also really works with hardware.

Its a software development cycle, that works nicely on the fact that software can be easily instrumented and tested automatically. An "internet of things" approach to space flight would be nice, but it does currently not even work for simpler products. Just remember that you not just need to develop the actual flight article and its documentation, but also the test systems and ground equipment so it can be included into a dynamic test campaign.

And as it looks right now, it does not have any advantages over classic aerospace development models at all.

 

[Col_Klonk]

What are you talking about? Too tall? It's already proven that it can land this tall a rocket on land. Why land on a barge? So it can be recovered when the dV demands eliminate the possibility of a return to a ground based landing site.

No insurance claim needed, as this is their engineering testing, with a high chance of failure. The alternative is to drop it in the sea anyway, for a guaranteed loss. So your comments make no sense.

OK... a rocket on some legs (how big can you make them before it impacts badly on your Dv) land on a barge... WOW great stuff.. then mother nature says ..'watch this boyo'.. a slightly bigger swell than normal due to de/constructive wave interference... throw in a bit of a sea breeze... totalise all the forces.. and... Do I really have to spell this out :tiphat:

That leg looked like it gave way after being subjected to the forces resulting from the wave motion = size of stage ?
More legs will make little difference as the domino effect will tear them all... need stronger heavier (Dv) legs.

So what if it landed on land ok..great stuff for SpaceX...
Of course it can land on the spot marked X...buuuutttt landing at sea - What we have here is a 'guaranteed disaster'.. So why even do it in the first place.. The penny drops - to get rid of the stage, after all it's paid for itself and a little bit extra from a claim or two ??

OK! so a stage does land on a barge in one piece... great.
The success rate would be interesting as launches will be affected by another factor - sea conditions a few miles away. This is not something you really want if you need a consistent launch rate = $$$.
:facepalm:

 

[Lmoy]

So why even do it in the first place.. The penny drops - to get rid of the stage, after all it's paid for itself and a little bit extra from a claim or two ??

Booster stage recovery is obviously going to be tricky, unreliable business for a while yet, and may not ever be fully reliable, but (depending of course on refurbishment costs, which we don't know yet) it's likely that even with occasional losses, the amount saved on the successfully recovered stages will make back the amount lost on the lower payload of reusable rockets. It's at least worth giving it a try, in my opinion. After all, nobody has ever demonstrated that reusable rockets don't work, and a few crashes in the beginning is nothing given they have demonstrated that stage recovery is indeed possible.

 

[Cairan]

Sure, absolutely. But then, SpaceX is also no "rocket stage landing research program" of NASA, but a commercial venture (though it received a huge pork barrel via NASA).

Last time I checked, they do succeed in launching commercial payloads to space... The experimental phase is the first stage landing at this point. You guys really are in full black and white mode... :facepalm:

When the discussions are much more informative and good humoured on the Facebook pages pertaining to spaceflight than on this forum, I think it says a lot about the state of this community. These threads have become unbearable to read with the back and forth thrown around.

:leaving:

 

[Col_Klonk]

You guys really are in full black and white mode... :facepalm:

Not really!

This decision for a barge landing.. while it's an idea to see if they can do it.. can it be done reliably and economically, compared to land landings

The risks look to outweigh the benefits as the unknown factors will always be the sea and local weather conditions, and these can restrict launchings so they end up being not viable in the long term.

Critical yes.. but with good reason... as even an aircraft carrier will not be a stable landing platform.

It might be a better idea to launch over the desert regions and operate landing pads in those areas than barge landings, as land landings are workable.. as proven

 

[Pipcard]

I really hope they can reliably land rockets on a barge, because it allows for first stage recovery with less payload penalty.

 

[Dantassii]

I believe that the barge recovery is planned to be the primary recovery mode for the Falcon 9 Heavy 1st stage core. The 2 boosters will fly back to land (that will be impressive to watch) while the core goes on to land on the barge. Although they have shown videos of the core making it back to land, the performance loss for doing that will limit it to missions where the Falcon 9 Heavy is under-loaded I suspect.

And as my signature block says.... The one who says it cannot be done.. should not interrupt the one doing it.

Dantassii

 

[ADSWNJ]

Not really!
The risks look to outweigh the benefits as the unknown factors will always be the sea and local weather conditions, and these can restrict launchings so they end up being not viable in the long term.

Clearly SpaceX thinks differently, and good for them for having the courage to try something never done before. Isn't this what true innovation and discovery is all about? Or shall we all just give up if it looks risky. (smh)

 

[RGClark]

Damn, they did stick that landing.
It is really horrifying to see how readily these things explode. As soon as it touches the deck *BOOM*.
CRS-6 was much more violent.
They have to do something about those legs. All four legs have to work. They hit me as being the least robust components on the entire rocket and have no backup.

Good point. It's what they call "single-point failure" when they have no redundancies. Perhaps they should have more legs.

Also, with aircraft they have indicators on whether the landing gear are locked. I wonder if they have this on the F9. Couldn't do much in this case though. With aircraft you can go around to give more time to get the gear locked or prepare for emergency landing if they can't.

Bob Clark

 

[MaverickSawyer]

I suspect that they DO have indicators, and that's why they cut the feed when they did... three green lights, one red.

 

[Thunder Chicken]

Did I mention it was too tall a stage for this type of landing. ?

Spot on landing... but why land on the barge when it's not proven yet, even with a smaller rocket.
There will probably be an insurance claim on this ??

The height of the stage means very little. The center of gravity of the nearly empty stage is well down near the engines.

They need to prove that they can land on a barge. The behavior of a small rocket does not tell you what a large rocket will do. Instead of simply dropping the stage into the ocean, they decide to test the real thing in real conditions, with the understanding that these are test flights and they might have to crash some rockets before they figure it out.

I'm pretty sure there is no insurance for test landing of a rocket on a barge, nor much real fiscal loss. The stage did its job to help get Jason-3 to orbit. Everything else gets chalked up to R&D.

---------- Post added at 06:32 PM ---------- Previous post was at 06:25 PM ----------

Good point. It's what they call "single-point failure" when they have no redundancies. Perhaps they should have more legs.

Or fewer legs. In the case of three legs, you still have failure if one of them fails, but your odds of equipment failure are decreased by decreasing the number of legs, assuming that the bigger legs are equally likely to fail as the smaller legs.

Why can't SpaceX exercise and test leg deployment on the pad like Blue Origin? They do the static fire to ensure systems are ready for launch, why not cycle the legs through landing and lock while they are doing so?

 

[MaverickSawyer]

Can SpaceX exercise and test leg deployment on the pad like Blue Origin? They do the static fire to ensure systems are ready for launch, why not cycle the legs through landing and lock while they are doing so?

Doubtful. There's not enough space around the booster.
Also, this is supposedly caused by icing due to the foggy weather. I suspect that a few small heating elements, or a slight redesign of the mechanism, will eliminate this failure mode.

 

[Urwumpe]

Also the legs are deployed by pyrotechnics, its very hard to test this before launch without ruining the test.

Maybe it would be better to simply use the inverse concept of how the Space Shuttle landing gear worked: If hydraulics failed, pyrotechnics opened the uplocks.

In this case: Force a lock by a pyrotechnical system.

 

[Thunder Chicken]

Also the legs are deployed by pyrotechnics, its very hard to test this before launch without ruining the test.

Maybe it would be better to simply use the inverse concept of how the Space Shuttle landing gear worked: If hydraulics failed, pyrotechnics opened the uplocks.

In this case: Force a lock by a pyrotechnical system.

In that case it is doubly unfortunate as you have a single point failure mechanism that you can't test. And the success or failure of the entire system (technically and economically) hinges on it working. This system needs either A) a lot more simplicity B) robustness, or C) redundancy / back up in order to work consistently.

No sir, not a fan of the legs.

 

[Urwumpe]

In that case it is doubly unfortunate as you have a single point failure mechanism that you can't test. And the success or failure of the entire system (technically and economically) hinges on it working. This system needs either A) a lot more simplicity B) robustness, or C) redundancy / back up in order to work consistently.

No sir, not a fan of the legs.

What do you want to use else, than legs? Arms?

A pyrotechnical system can be made redundant easily in multiple ways (dual igniters, dual actuators, dual hooks).

BTW: How professionals land on a ship:

 

[Artlav]

Can't quite see - does the pilot just flatten the blades or actually reverse the pitch after contact?
The heli looks like a giant leaned on it - is it just it's weight?