Space exploration: Where do we go from here?

[MichVandal]

Apollo started in 1961, JFK’s “We Choose To Go To The Moon” speech was in September 1962, NASA was regularly going to the Moon by 1968.

SpaceX was founded in 2002, still can’t get out of orbit in 2023.

For the starship, sure. But the thing that really, really bothers me is how many successful Falcon and Falcon Heavy launches they have had and they have these kinds of problems? Did they not learn anything, or are those rockets just as risky as these?

The actual engines are the same ones they use- the only real difference is the heat in the middle of the array. So when the booster tipped over to return, they have had so many launches that they should very well know the fluid dynamics they are dealing with. As for the upper stage- same thing.

[Handyman]

Apollo started in 1961, JFK’s “We Choose To Go To The Moon” speech was in September 1962, NASA was regularly going to the Moon by 1968.

SpaceX was founded in 2002, still can’t get out of orbit in 2023.

Imagine this...there are people lining up to fly to Mars on one of his death traps! Probably sad they missed their chance to see the Titanic!

[aparch]

For the starship, sure. But the thing that really, really bothers me is how many successful Falcon and Falcon Heavy launches they have had and they have these kinds of problems? Did they not learn anything, or are those rockets just as risky as these?

The actual engines are the same ones they use- the only real difference is the heat in the middle of the array. So when the booster tipped over to return, they have had so many launches that they should very well know the fluid dynamics they are dealing with. As for the upper stage- same thing.

It's an issue the Russians once had and they abandoned themselves: less engines is better.

They also saw many rockets fail with their excess of engines and found they had to cut down on them.

Musk thinks the more the better despite 80 years of rocket history.

[MichVandal]

It's an issue the Russians once had and they abandoned themselves: less engines is better.

They also saw many rockets fail with their excess of engines and found they had to cut down on them.

Musk thinks the more the better despite 80 years of rocket history.

Isn't the F-1 in the public domain? And NASA developed a 3d printed version of that, too- which should also be available. For enough years now that it could be developed into a usable motor. Use 6 of them instead of Saturn's 5. Done.

(that's purely speculation, BTW- but more frustration with X and elon.

[Kepler]

How do you do fewer engines and get the same thrust? More powerful engines? Or can you "work smarter, not harder"?

[Jimjamesak]

How do you do fewer engines and get the same thrust? More powerful engines? Or can you "work smarter, not harder"?

More powerful engines. Saturn V used five massive engines, the Soviet N1 used a cluster of 30.

[MichVandal]

How do you do fewer engines and get the same thrust? More powerful engines? Or can you "work smarter, not harder"?

F-1.

If I do my calculation right, one of the Spaceship motors generates 515k lb of thrust each, the F1 makes 1,750k lb of thrust each.

So instead of 30 motors to get right, you need 10.

And there was an update "design" to the F1 that should make it easier to make. With X's experience, they should be able to do even better as well as make sure it's re-light able.

[MichVandal]

How do you do fewer engines and get the same thrust? More powerful engines? Or can you "work smarter, not harder"?

There's also a "smarter, not harder" aspect, too. Looking back into history, NASA originally thought of the concept of a huge ship that lands and takes off from the surface of the moon. And then they calculated how much that would take in terms of thrust and fuel. IIRC, it took more than a lb of additional fuel to each lb of mass going to the moon, let alone the needed thrust. It was not a linear relationship. And going to Mars is even worse.

That's why instead of a massive body to go to the moon and back, it was modular, and only the tiny command module was designed to get back to the earth's surface.

It's a massive problem.

Another "smarter" thing to do is to not have one single body launched. SpaceX has gotten proficient at orbital connection, right? So instead of one massive rocket, launch two smaller ones. Or even three. Have a command module, then a living module, and perhaps a rocket module launched separately. They could pretty easily do this in a day.

And one more "smarter" is to add complete booster rockets. Like Space Shuttle did- and it's pretty common for launches outside of earth orbit these days. This is the one that is probably the most curious thing now- SpaceX has done this already. They have launched rockets where the two side booster rockets landed near the launch pad, and then the main segment landed on a barge in the Atlantic.

Basically, there are multiple ways to the solution over the single out and back space craft.

[aparch]

I wonder if part of the problem is the volatility of the fuel used. The Apollo F1 and SpaceX Merlin Engines use Liquid Oxygen. Starship's Falcon engines use Liquid Methane.


But overall, more powerful engines and less of them are much more successful than throwing a sh**ton of lower powered engines on a rocket.

[dxmnkd316]

There's also a "smarter, not harder" aspect, too. Looking back into history, NASA originally thought of the concept of a huge ship that lands and takes off from the surface of the moon. And then they calculated how much that would take in terms of thrust and fuel. IIRC, it took more than a lb of additional fuel to each lb of mass going to the moon, let alone the needed thrust. It was not a linear relationship. And going to Mars is even worse.

That's why instead of a massive body to go to the moon and back, it was modular, and only the tiny command module was designed to get back to the earth's surface.

It's a massive problem.

Another "smarter" thing to do is to not have one single body launched. SpaceX has gotten proficient at orbital connection, right? So instead of one massive rocket, launch two smaller ones. Or even three. Have a command module, then a living module, and perhaps a rocket module launched separately. They could pretty easily do this in a day.

And one more "smarter" is to add complete booster rockets. Like Space Shuttle did- and it's pretty common for launches outside of earth orbit these days. This is the one that is probably the most curious thing now- SpaceX has done this already. They have launched rockets where the two side booster rockets landed near the launch pad, and then the main segment landed on a barge in the Atlantic.

Basically, there are multiple ways to the solution over the single out and back space craft.

Honestly, and I don't mean to oversimplify this, this is the kind of remedial stuff you can learn in KSP. Which is why it's so infuriating that SpaceX is repeating these dumb... I'm trying to find a word because 'mistakes' isn't appropriate, these are fairly well-known concepts and it's like they're trying to prove them wrong. Which is... expensive.

[aparch]

Modularity is also why a space station waypoint or "gas station" on the Moon has always been considered for flights further into space: its easier to throw a bunch of smaller items into orbit/park on the Moon than it is to drag everything out to Mars with us.

[dxmnkd316]

Modularity is also why a space station waypoint or "gas station" on the Moon has always been considered for flights further into space: its easier to throw a bunch of smaller items into orbit/park on the Moon than it is to drag everything out to Mars with us.

Easier and if an entire flight fails, you aren't starting from scratch. It's compartmentalizing the risk. You do this every time you bake a cake and crack eggs into a small bowl instead of adding directly to the mixing bowl.

[MichVandal]

Honestly, and I don't mean to oversimplify this, this is the kind of remedial stuff you can learn in KSP. Which is why it's so infuriating that SpaceX is repeating these dumb... I'm trying to find a word because 'mistakes' isn't appropriate, these are fairly well-known concepts and it's like they're trying to prove them wrong. Which is... expensive.

Exactly. Why reinvent the wheel? Even the wheels that you already developed.

Seems more ego than logic driven.

While the Soviets had to learn the hard way that so many engines is a real problem- they did it that way as it was the fastest solution given they had those engines developed for their ICBMs. Given NASA and the USAF were not the same body, and there was no way the USAF would want their ICBM engines public- NASA had to start from scratch.

[Handyman]

Ego is part of it...in the need to be seen as the genius who revolutionized space travel and so on. If Elmo and crew just update what came before them they will be seen as heroes but not above those that came before. If you come up with something new now you are on the level of the greats.

Elmo doesn't want to be some no named NASA engineer that is forgotten to history...he wants to be Edison or Tesla. A name that will always be known.

[LynahFan]

Even on airplanes, fewer engines is better....down to a point. If you're flying over water, redundancy is nice. But fewer bigger engines is such a huge cost incentive that the regulating agencies have developed a certification called "ETOPS," (which officially stands for "extended twin operations" but is better known by running industry joke as "Engines Turn Or People Swim"). Without ETOPS, twin engine aircraft have to be within 60 minutes of flight time (on a single engine) of a suitable divert runway at all times. You can get ETOPS ratings to allow longer times, up to 330 minutes, which basically covers 100% of the earth's surface.

So you can be a less nervous flyer, ETOPS certification is based not only on the design characteristics of the airplane ("how many redundant fuel pumps do you have?") but also on the actual service history of the planes, as maintained by the operator. So if United maintains their planes better and experiences fewer failures as a result, they may be able to get certified for more minutes of ETOPs than American can for the exact same type of aircraft. Going for an ETOPs cert therefore means that the airline has committed to collecting and documenting all the right failure rate data (in perpetuity, not just a one-time thing) to prove to the FAA that ETOPs is low risk - and going to all that trouble is still cheaper than adding a 3rd or 4th engine.