SpaceX Space X reusable rocket landing

[artis]

No @mfb My thinking was different. It is a well known fact among the automotive mechanic circles that many brands made far more reliable and longer lasting vehicles back in the 80's and 90's and some into early 2000's than they do now, I guess you could say it's part of planned obsolescence.
The manufacturer now just calculates how long something has to last and then searches for the cheapest material that still fits the bill. Thanks to modern computer simulation they can do this without worries as back in the day one had to put in more "reserve" capability in order to be sure not to fail.

But I guess this logic applies more to the wider consumer industry where parts and tings are bought by the millions so the companies are interested in continually upgrading and introducing new stuff so their kind of interested that the old stuff doesn't last forever, I guess aerospace would have a bit different approach due to the high cost and not go that same route,

although who knows , I'm kinda skeptical but they are trying to 3d print boosters etc to the point where they would become extra cheap and could literally be recovered as scarp and recycled.
I guess there must be a line of cost per booster below which it would become useless to recover it, interesting to see whether we will go back to single use boosters again to close the circle once our manufacturing capability will take a another step further.

 

[mfb]

Planned obsolescence would make no sense in an industry where the manufacturer sells the rides, not the vehicles. You don't buy a rocket. You buy a ride to space. If the manufacturer of the rocket can reuse it instead of building a new rocket they save money. If they can reuse it 100 times instead of 5 times they save more money, so SpaceX tries to reuse their rockets as often as feasible. If components are known to break down earlier than other components then these components can be exchanged while the rest keeps flying.

Sure, there is no point in qualifying something for 10,000 flights because Falcon 9 will not make that many.

 

[trurle]

well i guess so since now every part of a complex system can be engineered to precise limits , manufacturers usually take the route of using the cheapest material possible that can still do the job within limits ,but then again looking from this logic what's the point of a re-usable rocket booster in 2020 apart from being cool and geeky?

because in most other areas we now do the exact opposite , we for example don't build cars that last a millenium anymore instead we build cars that mostly last their warranty, the same logic goes to most other products,

30% per-flight cost reduction for Falcon 9 reusable boosters is actually bordering no-significance zone. Currently SpaceX got a small competitive advantage thanks to reusable booster, but it is uncertain if advantage will remain. The reversion to fully expendable boosters in future, even within SpaceX, is possible.

 

[mfb]

30% price difference is a lot.

The reversion to fully expendable boosters in future, even within SpaceX, is possible.

I would like to see a reference for that claim, or at least a good argument.
Why would SpaceX choose to spend more money on flights and slow down their flight rate for no gain?

 

[artis]

please go to 0:26 and watch the booster that flipped midair , now in all the fail videos the booster always explodes , I would think that this is not some built in self destruction but merely a side effect from the booster propellants?

In this video we see that as the booster flips midair it almost immediately after explodes midair without hitting anything, is this because of the way the fuel is stored in the fuel tanks or something and it then mixes and ignites?

Because so far I have understood that there are 2 things in the booster that tend to explode , in the upper stage some sort of what appears to be a highly compressed gas and in the lower stage the rocket propellant.

 

[glappkaeft]

You have not really produced any reason why you think that? Besides SpaceX thinks they used the flight termination system.

 

[Rive]

The reversion to fully expendable boosters in future, even within SpaceX, is possible.

Indeed possible but it would require quite a bit of funds spent on the administration to force them through regulations.

It is far more likely that in the next years partial recovery of the launch device will become the standard practice (at least, for those who has some capital to spend on development).

 

[mfb]

Grasshopper (0:26) was destroyed intentionally after it got out of control. The rest exploded when it hit the ocean/ship.

One of the boosters (B1050) landed in the water without an explosion - here is a video. The rocket was planned to land on the ground pad. The trajectory always aims at the ocean and the booster changes its trajectory to the shore only if everything is fine. It wasn't, so it aimed at the ocean. You can see the excessive roll (rotation around its long axis). Shortly before hitting the water it seemed to regain control. The booster was too damaged to fly again, but it's possible that they reused some parts.

 

[artis]

@mfb maybe you also happen to know what type of device they use to destroy the rockets intentionally, I assume it's built into all the boosters for "just in case" situations.

 

[jackwhirl]

@mfb maybe you also happen to know what type of device they use to destroy the rockets intentionally, I assume it's built into all the boosters for "just in case" situations.

That's the Flight Termination System. In SpaceX videos, you occasionally hear the mission control call-out "stage one FTS is safe", meaning the system has been disabled or "rendered safe" after the rocket reached a safe altitude or trajectory.

 

[artis]

Well I guess this systems helps so much so that instead of having a whole booster fall on your car or property you end up with thousands of pieces falling on your car or property, still better.

 

[mfb]

The trajectory doesn't go over inhabited area. As long as the rocket explodes before it deviates too much from its trajectory the debris just falls into the ocean. Or on deserts, remote farmland or similar for some suborbital rockets.

 

[glappkaeft]

The main purpose of the Flight Termination System is to terminate the thrust of the rocket so that it doesn't go any further off-course. Secondary but also important is to disperse and/or ignite the remaining fuel and oxidizer.