HN Theater @HNTheaterMonth

⬐ jlgreco

Similar work has been done by Armadillo, but it looks like SpaceX's Grasshopper is a bit bigger than anything Armadillo has done. Will be exciting to see the concept continue to scale up.

⬐ Gravityloss

There are many other groups as well. These two competed in Lunar Lander Challenge in 2009 and have flown vertically landing rockets:

- Masten Space Systems: https://www.youtube.com/user/mastenspace

- Unreasonable Rocket: https://www.youtube.com/watch?v=_PO5cTb_T5M (Couldn't find a better video now)

⬐ gnarbarian

Bigger but this [1] test by Armadillo was more impressive in my opinion for the additional complexity involved in cutting the engine deploying a chute then cutting the chute and successfully landing from a turbulent freefall.

[1]https://www.youtube.com/watch?v=9u0qlIoSSkQ

⬐ ramidarigaz

I knew armadillo was doing some impressive work, but wow. That was really cool.

⬐ eps

2010 :-|

⬐ gnarbarian

Hey cut him some slack he had to go finish RAGE and do his day job.

⬐ tsotha

Yeah, they seem to have stalled in recent years. Either Carmack has lost interest or they've reached the point of complexity where a few volunteers aren't going to cut it.

⬐ Gravityloss

Armadillo has recently flown the Stig and Stiga rocket quite high with succesful recovery.

Since they have the landing and low speed part pretty much covered, they're now looking at the high speed and altitude problematics.

The Stig lands with a steerable chute.

High speed stability, drag and turning for powered landing are a nasty problem field where testing is hard and expensive. Interplay of aerodynamics in a wide speed range, center of gravity shifts and everything else.

Burt Rutan's SpaceshipOne solved it elegantly with feathering: the descent was safe and easy. The mechanism could be troublesome though.

https://www.youtube.com/watch?v=WXKQ0v_YPWw

⬐ tsotha

>Burt Rutan's SpaceshipOne solved it elegantly with feathering: the descent was safe and easy. The mechanism could be troublesome though.

I wouldn't put too much stock in SpaceshipOne's descent scheme. It's not clear at all that's going to work from orbit.

⬐ Gravityloss

Maybe, maybe not.

And for a first stage, returning is not nearly as hard.

At first, the reusable first stage might provide only a modest portion of the delta vee and an expendable second stage would do most of the work. That would mean a low payload.

I don't think the SpaceshipOne solution would work "as is", but something like it might work. It only went vertically to 100 km.

When the Space Shuttle was being designed, Max Faget toyed around with different ideas on how to arrange re-entry, with essentially something similar as SpaceshipOne in a sense: a high drag configuration at high speed and then flying at low speed. http://www.astronautix.com/lvs/shuenara.htm

⬐ tsotha

Sure, the first stage is easy from an energy perspective, so SpaceshipOne is a good model for that. From what I understand they intend to try to use the same idea for reentry from orbit, though, and I think they'll end up with something expensive and dangerous as a result.

The space shuttle was a disaster from a cost perspective. I don't know how many lessons we can draw from the program beyond "don't do it this way".

⬐ Gravityloss

Though Virgin Galactic is very far from orbit yet. They've been doing glide flights with SpaceshipTwo for years since their big hybrid rocket motor has not been progressing very fast and even had a ground accident. Stuff like that can happen if an airplane body company builds a rocket ship.

We can draw a lot of lessons from the space shuttle - it was very successful in lifting re-entries. It takes a huge amount of expensive wind tunnel and test time to develop something like this.

Why STS was so expensive must be analyzed more deeply - we definitely can not afford to waste all the lessons learned in that program. I think, in details, it contained many technologies that were not robust and required lots of checking and hand work (people with salaries). This also made it less reliable. Strategically, it was a huge one off program, meaning there was no possibility of iteration and trial and error: feeding information from operations back to improving design. (Cue Gall's law.)

Since development is so expensive (afaik a lot of the testing infrastructure has been driven down), this is also why most space capsules use known-to-work shapes: Vostok, Mercury, Gemini, Apollo or Soyuz. Some small capsule designs have even used Corona spysat film return canister shape.

⬐ BHSPitMonkey

I finished that video thinking, "huh, that guy looks/sounds just like Carmack". Sure enough...

I had no idea he was involved with a project like this, and for so long. Too bad they don't appear to have been very active recently.

⬐ ChuckMcM

Ok, that video is just freakin' amazing. Lets count the things they show in it:

1) Take off from the pad.

2) Loss of vehicle control (chute deploys), Loss of engine

3) Engine restart.

4) Attitude recovery after engine restart

5) Return to pad capability.

I had no ideas these guys were that far along.

⬐ snogglethorpe

> I had no ideas these guys were that far along.

... with what, like 0.0001% of SpaceX's budget and other resources...?

Maybe SpaceX should hire Armadillo...

⬐ robryan

They should acquire them and give them the freedom to keep doing stuff like this independently, just advancing SpaceX goals.

⬐ None

None

⬐ ChuckMcM

Its an intriguing question isn't it? Here we have two companies which together have all the moving parts necessary for a lunar landing and return mission. It would be fascinating if Bigelow Aerospace could put a habitat at the Lunar L1 point. Then SpaceX provides a boost to L1 capability, and Armadillo provides a transport service from L1 to/from the surface of the Moon.

⬐ turing

For those interested, here is a similar video from Jeff Bezos' Blue Origin last year.

http://www.blueorigin.com/updates/updates-2011-11-17-video-o...

⬐ thematt

Thanks for the plug :) Here's another one: I'm looking for some top-notch software engineers if anyone is interested.

⬐ DVassallo

Can you tell us what the "... or otherwise able to review all export-controlled technical information" point in the qualifications means? How would one be able to determine if he/she is able to do that. Is it nationality related? [I have no knowledge of this space, so excuse me if this something obvious.]

⬐ thematt

All private space companies fall under the umbrella of ITAR.

http://en.m.wikipedia.org/wiki/International_Traffic_in_Arms...

⬐ neurotech1

A significant amount of rocket technology is covered by ITAR (International Traffic in Arms Regulations), which means that its restricted to largely US citizens. That means it cannot be legally shared with foreign college students, for example. The first rockets were basically ICBMs without the warhead. Gemini capsules were launched from a Titan II rocket, for example.

⬐ DeepDuh

In other words, say I'd like to apply to SpaceX as a European software engineer, it won't be possible?

⬐ TeMPOraL

Unfortunately not.

⬐ DeepDuh

That's a shame. Does anybody know whether it's the same in the UK? Project Skylon seems very promising.

⬐ None

None

⬐ neurotech1

I should have said "US Persons" not "US Citizen" above.

I'm not sure about SpaceX specifically, but if you were a Green Card holder. e.g O-1 Exceptional Ability, then you'd be considered a US Person for ITAR compliance.

From http://www.spacex.com/careers.php "To conform to U.S. Government space technology export regulations, applicant must be a U.S. citizen, lawful permanent resident of the U.S., protected individual as defined by 8 U.S.C. 1324b(a)(3), or eligible to obtain the required authorizations from the U.S. Department of State."

It doesn't sound like SpaceX require a Secret/Top Secret clearance for most of their employees. Some other space companies (Orbital Science Corp, ULA/Boeing/Lockheed Martin) do because they work on missile systems like ICBMs in related programs.

From what I understood, most engineers who make the grade to work at SpaceX, would be O-1 visa eligible as well. The O-1 is not tied to continued employment at a particular company.

⬐ DeepDuh

Great info, thanks!

⬐ cryptoz

Hello! I have applied to Blue Origin in the past but have not got very far. I have been working very hard to improve my skills, I recently interviewed on site at SpaceX (but didn't get it) and I'm trying my hardest to write the best code I can in order to improve my chances at helping people build space ships.

Do you have any advice for my next application to Blue Origin? My strongest points are my unending passion for spaceflight, science and desire to better myself. My code and software engineering skills improve by the hour (...it's Christmas in two hours and I'm working on pressureNET and reading HN). I have some excellent projects under my belt but I have no experience working on spaceships or related systems.

But I'm not sure what else I can do. So if you have some advice that would be fantastic.

Edit: And yes, I'm a US citizen.

⬐ eps

In many cases a choice between passionate intermediates and indifferent seniors boils down to whether they have a capacity for mentoring, which is a demanding process.

⬐ cryptoz

That is very much what SpaceX said to me, and so I've spent the last few months working as hard as I can to become top-notch so they'll pay attention.

I know that I need to improve. I am still hoping that there are other angles, other things I can do, so that the answer to my question is NOT "25 year olds are bad. Come back when you're 40 and already have three of your own spaceships in orbit".

⬐ samishxc

In what ways will this be useful? I imagine if a rocket carries a payload into space it wouldn't be able to land vertically like this, or is that the intention?

Either way, very interesting

⬐ dangrossman

Fly to Mars (or anywhere else in the solar system), land, unload passengers and cargo, refuel, take off again, fly to Earth, land. Refuel and start loading for the next flight.

That's the end goal. And since not all bodies SpaceX may want to land on have a comparable atmosphere to Earth, parachutes are not part of the plan.

This isn't the vehicle that's going to do all that, but they have to start somewhere to build the tech that eventually will.

⬐ dotborg

I doubt this vehicle will be used for landing on Earth(why not use parachutes?). I would rather send it to Mars orbit and reuse it there as a landing module, but not take it back to Earth.

⬐ gus_massa

The auxiliary solid fuel rockets of the space shuttle slashed in the sea with parachutes and were "reusable". But they were so bumped that the refurbishment procedure involved a lot of handwork and iirc more than a month.

⬐ JulianMorrison

Why not use chutes? Because with rockets, you can steer, and fine-tune the rate of descent. You don't need to splash down at sea, you can land on solid ground, and pick which bit of ground to land on (such as a spaceport). It's less of a bumpy ride and cheaper to recover.

⬐ JulianMorrison

More like: launch to earth orbit (dropping the first and second stages, that land at spaceports for shipping home and refuelling), dock to a larger ship (nuclear?) which carries them to Mars, un-dock in Mars orbit and make a powered descent to the colony there. And then do the whole thing again backwards.

⬐ InclinedPlane

The intention is to make both stages of the Falcon 9 reusable and to have them land vertically back at the launch site. This does add weight, for thermal protection and landing gear, and it uses up some propellant but on the whole the savings in capital and operational costs should more than make up for it. Right now the entire rocket is thrown away for every launch, which is hugely expensive. But if they can manage to get dozens of launches out of each vehicle then they can reduce costs by a huge margin even if payload is cut in half or worse.

⬐ annon

The objective is to have reusable stages. Instead of letting them burn up in the atmosphere, they land vertically to be reused.

⬐ neurotech1

Typically the first stage is destroyed during impact with the water(or ground). The Shuttle SRBs were generally recovered undamaged, but relied on large parachutes and were towed back using a specialized ship.

SpaceX Grasshopper avoids either destroying the first stage, or a labor intensive and expensive recovery process.

⬐ stcredzero

The SRBs were generally recovered bent or squished. There was actually a machine to bend the stack segments back to round.

⬐ neurotech1

Do you have a reference for that? I thought the SRB segments are quite structurally strong and the parachutes quite large and effective.

⬐ stcredzero

> Do you have a reference for that?

No, but I'm sure I read that right and the machine existed.

> I thought the SRB segments are quite structurally strong and the parachutes quite large and effective.

They are, but the stresses are large, the diameter is large, and the requirements quite stringent. If a casing is out of round by a small fraction, this might still cause the o-rings to not be pressed against the casings tightly enough.

⬐ ramidarigaz

Like the other commenters gave said, landing vertically is very much their intention. The rationale is that sea landings make repair work much harder.

⬐ nickik

> The rationale is that sea landings make repair work much harder.

Ist the much more importend things the time and cost of getting the rocket back to where you want it much bigger?

⬐ ramidarigaz

I imagine that's a factor, but it's primarily the fact that sea water is really hard on the delicate parts of the rocket due to corrosion and mineral deposits.

⬐ riffraff

then wouldn't it make more sense to just build a very big pool/use an unsalty lake ?

You'd still need to steer the rocket there but you can avoid worrying about vertical landing.

⬐ cryptoz

Mars does not currently have lakes.

⬐ stcredzero

There was an SSTO proposal from the 1970's that did involve building a huge splashdown lake. That proposal also used vertical landing, however. (The craft was so large, landing gear would've been prohibitive, so the whole thing just floated.)

⬐ jacquesm

And very rapid cooling as well as the chance of impact damage. Sea landings may look gentle but really they aren't.

⬐ None

None

⬐ mkuhn

Had a few too many!? As the Hacker News Pro you claim to be you definitely did not find the right tone or even the right comment to reply to...

⬐ arrrg

Fourth, don’t be mean. I think you are part of the problem, honestly. (As am I, admittedly.)

Merry Christmas!

⬐ jlgreco

It is important to keep in mind that the fuel costs for bringing a stage back down are far lower than the cost to put it up there, since most of the mass (fuel) will be burnt off before the return leg starts.

Since fuel is the cheap part anyway, Space X is betting that they can make it economically sound to launch a bit more fuel than they would normally need to if it means they can get the (expensive) rocket stage back.

⬐ tsotha

This is great and all, but it's been done many times since the 1950s.

⬐ Gravityloss

As far as I know, this is only the second turbopump fed liquid rocket to land vertically, after DC-X (that became DC-XA).

http://www.youtube.com/watch?v=wv9n9Casp1o

This is important, as in practice only turbopump rockets have enough performance for orbital uses. If it can routinely and safely land vertically, then it's very easy to build a reusable first stage out of this.

If everything works out, a reusable Falcon could fly every few days: Ideally you'd just refuel and go again, like an airplane.

In this first generation though I expect a lot of maintenance and handwork by lots of people every flight.

This will require a whole ecosystem too: low maintenance satellites that can be slapped on the rocket and launched at any time. Otherwise very flexible operations too like low overhead range and radar tracking sevices, safety zones etc.

If the rocket can abort and land in case of problems, and demonstrates good safety by flying a lot, then a lot of safety criteria can be relaxed, which should enable better flexibility.