SpaceX just made history.

[Ruffdaddy]

So, again, having some sort of redundant "catch" system would be prudent, then, no?

Not if that catch system decreases the probability of a successful landing from the primary system.

[GhostTX]

Not if that catch system decreases the probability of a successful landing from the primary system.

As I alluded to, like the safety rigs on carriers, it's a system that can be deployed in an emergency. Say, sensors on the barge detect the booster listing at too much an angle and then the nets activate like an airbag in a car.

[Ruffdaddy]

As I alluded to, like the safety rigs on carriers, it's a system that can be deployed in an emergency. Say, sensors on the barge detect the booster listing at too much an angle and then the nets activate like an airbag in a car.

Great idea. Sketch it up, patent it then sell it to them.

[GhostTX]

Great idea. Sketch it up, patent it then sell it to them.

From a SpaceX "geek" forum:

Everything you say has been proposed and shot down many times. My understanding is that the booster is only designed for loads in the longitudinal direction, and any impact on the sides makes the stage go kaboom (even more because it is pressurized). Furthermore these systems would have to be made such that do not interfere with a successful landing.
And as we have seen, once the bugs are worked out, rocket landings are precise to the meter, and when there are bugs, you never know exactly how in advance so your safety system may be useless.

[Ruffdaddy]

From a SpaceX "geek" forum:

Why do you think i stopped debating this and said design it?

Its a similar response i give anytime someone asks me to machine something real quick. They either give up on the sketch phase or they realize the magnitude of the effort while sketching and stop asking. Regardles of which path they take... the outcome is the same for me.

At some point, explaining technical details to non technical people is fruitless because they just havent been through the process to know better....and for some reason like to argue as if they do.

[svauto-erotic855]

I know enough about him to know your statement is far-fetched.

I never said that the man was dumb, quite the contrary. I believe that he is brilliant but he is an ideas guy/academic and not an engineer. It takes some one with vision and unwavering determination to inspire others like he has.

[mschmoyer]

I don't get the "interference" reasoning. If the rocket is so far off that it is going to hit a net or a tower, then it certainly has one leg going into the water and it's moot anyways.

The side-loading issue makes more sense. Just seems like you could engineer something to catch it easier than landing a pencil on it's eraser on a bobbing ship.

I was also thinking about how expensive the engine section is compared to the rest of the ship. What if they just brought back the lower quarter or so. Is that $45 mil of the $60 mil total?

[GhostTX]

Why do you think i stopped debating this and said design it?

Its a similar response i give anytime someone asks me to machine something real quick. They either give up on the sketch phase or they realize the magnitude of the effort while sketching and stop asking. Regardles of which path they take... the outcome is the same for me.

At some point, explaining technical details to non technical people is fruitless because they just havent been through the process to know better....and for some reason like to argue as if they do.

I hear you. Sometimes you just gotta ask "why"? Every now and then, the obvious isn't asked. Engineers sometimes get so focused on what they envision, they don't go outside that box. Doing a search on the geek site didn't turn up results, so I popped the question.

Just the cost of each $30 million booster going up in smoke each time it falls over is mind boggling. You'd think some sort of "pillow" would be created to save that, unless the $60 million charge for a launch covers that loss.

[Ruffdaddy]

I hear you. Sometimes you just gotta ask "why"? Every now and then, the obvious isn't asked. Engineers sometimes get so focused on what they envision, they don't go outside that box. Doing a search on the geek site didn't turn up results, so I popped the question.

Just the cost of each $30 million booster going up in smoke each time it falls over is mind boggling. You'd think some sort of "pillow" would be created to save that, unless the $60 million charge for a launch covers that loss.

Youre absolutely right...tunnel vision can play a toll on things. Ive also sat in many design reviews where an engineer was asked to fix something without making any real changes.

Im going to guess here, but i would imagine no airbag is in place because it probably wouldnt work well enough to truly save the structure. So its a big investment for very little return. And anything that is salvaged must be thoroughly inspected and then reassembled. Imagine if a part was thought to be good, but the rocket failed on launch...destroying itself and the payload. The margin for error is really small with this stuff.

In my job, tools that go offshore are given more scrutiny because of a similar rationale. Deepwater rigs can run over a million a day...if your tool shuts down a rig for just a day the cost can be substantial. Thus, every decision is made in a much more conservative manner than us land based where rigs may be an order of magnitude less. Even for many land based i will recommend replacing parts that may appear fine because of the cost of failure.

[Strychnine]

I want to know how they protect the landing gear and underside of the rocket form damage cause by back blast. I would also like to know what material the deck they are landing on in made of. Both of these things were huge engineering hurdles during the Apollo program and were solved but the "Cures" were massive.

The Marmac 300 barge, which was modified into ASDS JRTI is made out of steel.

There has been a lot of modelling and debate in the NasaSpaceflight.com forums trying to estimate how thick. Current thinking seems to come out around 25-35mm (1 inch to a bit thicker) steel.

The heat load of a landing stage is not really that high. A single Merlin 1D at 70% thrust, for only a few seconds (2-3) on the surface is not enough to do a lot of damage.

http://space.stackexchange.com/questions/8842/what-is-the-spacex-barge-topped-with

The drone ship was fitted with deluge water jets that flooded the deck with ballast water from the barge’s tanks, for cooling the deck from the blast of the landing rocket engines.

Some time before the incoming stage was expected, the water pumps would be started and the deck flooded. Some of the on-deck photos later provided by SpaceX showed water jets flooding the deck as the incoming stage came into view.

http://www.nasaspaceflight.com/2015/06/spacex-augments-upgrades-drone-ship-armada/

[Sgt Beavis]

So he founded 4 tech companies solely on his promoting abilities?
Got it.

To be more accurate, with the exception of SpaceX, he founded all of his companies with a team of other people. SpaceX is the only one he put together under his own leadership.

[Sgt Beavis]

I hear you. Sometimes you just gotta ask "why"? Every now and then, the obvious isn't asked. Engineers sometimes get so focused on what they envision, they don't go outside that box. Doing a search on the geek site didn't turn up results, so I popped the question.

Just the cost of each $30 million booster going up in smoke each time it falls over is mind boggling. You'd think some sort of "pillow" would be created to save that, unless the $60 million charge for a launch covers that loss.

Don't forget, these landings are technically test flights. I think the main thing now is to get the landing system working as best as possible. They could consider redundancy systems at some point in the future.

[Strychnine]

I'm really not trying to be a fanboy here, but you don't make sense.

Elon Musk could not tell you how to use a screw driver. He is a great promoter but he is not a tech guy at all.

I never said that the man was dumb, quite the contrary. I believe that he is brilliant but he is an ideas guy/academic and not an engineer.

"I know my rocket inside out and backward. I can tell you the heat treating temper of the skin material, where it changes, why we chose that material, the welding technique... down to the gnat's ass."
- Elon Musk


Sounds like an engineer's mind to me (?)


In Forbes, Jim Cantrell (aerospace consultant) said this:

I helped Elon start the company and all of these answers are spot on. He still has my book on rocket propulsion.....

What I found from working with Elon is that he starts by defining a goal and he puts a lot of effort into understanding what that goal is and why it is a good and valid goal. His goal, as I see it, has not changed from the day he first called me in August of 2001. I still hear it in his speeches. His goal was to make mankind a multi planetary species and to do that he had to first solve the transportation problem.

Once he has a goal, his next step is to learn as much about the topic at hand as possible from as many sources as possible. He is by far the single smartest person that I have ever worked with ... period. I can't estimate his IQ but he is very very intelligent. And not the typical egg head kind of smart. He has a real applied mind. He literally sucks the knowledge and experience out of people that he is around. He borrowed all of my college texts on rocket propulsion when we first started working together in 2001. We also hired as many of my colleagues in the rocket and spacecraft business that were willing to consult with him. It was like a gigantic spaceapalooza. At that point we were not talking about building a rocket ourselves, only launching a privately funded mission to Mars. I found out later that he was talking to a bunch of other people about rocket designs and collaborating on some spreadsheet level systems designs for launchers. Once our dealings with the Russians fell apart, he decided to build his own rocket and this was the genesis of SpaceX.

[Sgt Beavis]

The Falcon 9 is a $60 mil piece of hardware and only about $250K of that is the fuel.

yes, roughly. However that covers the 1st and 2nd stage together.

I wonder how long before SpaceX starts test landings on the 2nd stage.

[ceyko]

Yes. Founded by Elon Musk - same guy who founded PayPal, Tesla, Solar City, etc. Basically Tony Stark.

Thanks man, appreciate it - fairly ignorant on the whole thing.

MSM today from what I saw made it out to be a complete failure and a joke. A little frustrating after what I've learned from this thread and basic googling earlier this morning.

Again, the media is public enemy #1.