
Space X CR6 First stage landing - atroyn
https://www.youtube.com/watch?v=rAzwuEmZcmE
======
rebootthesystem
Non-engineers see this as a failure. Engineers and scientists see this as an
awe-inspiring success from which to learn, iterate and try again. I don't
fault reporters for exagerated headlined focusing on failure. They don't know
any better. That is not what their lives are about and most might be
challenged to understand that nothing in that video constitutes failure in the
context of evolving a design. In fact, failure is absolutely necessary in
order to better understand the problem you are trying to solve.

~~~
_Adam
I don't agree that failure is absolutely necessary. I think success is
generally more informative, because it gives you data about something that
works end to end.

If your rocket blows up on the launch pad, you just learned that you shouldn't
overpressure your fuel tank (or w/e). But if your rocket lifts off, goes to
space, and lands, you learn thousands of things that work that you can use
again.

~~~
deeviant
I strongly disagree.

I have seen a company be destroyed because they got things almost right, from
the beginning. This "success" informed their every decision and created an
enormous resistance to trying anything new and in the end it turned out almost
simply wasn't good enough. The initial success destroyed them.

~~~
hga
That destroyed two Space Shuttles and killed their crews.

Both the failing field joints ("O-rings") and detaching external tank
insulation weren't _quite_ bad enough to kill a Shuttle, were all but ignored,
until of course they couldn't be ignored.

------
atroyn
I can't help but feel bad for that one poor little RCS thruster doing its
level best to keep the first stage upright, but ultimately running out of
fuel.

~~~
hyperbovine
Judging from the ensuing explosion there was still fuel left over.

~~~
darkmighty
Making it a little puzzling ask to why the engines didn't try harder to lower
the vertical velocity on approach. Perhaps there are improvements to be made
in the control systems.

~~~
fleitz
I have a feeling their engineers may have considered this. This is after all
rocket science.

~~~
darkmighty
I also have this feeling, but from my limited experience with control systems
you might want to try the simplest first.

There is a tremendous amount of variables to consider, and the analysis of how
to take each into account is non trivial -- if you don't measure some variable
precisely enough it might make the whole system less stable, the solution
might get worse due to increased computational load, the conditioning might
degrade, etc.

So with the number of controls they have and the predictive models available,
I'm sure they're actually scrambling to refine their systems right now.

~~~
will_hughes
The thrust to weight ratio of a single engine firing is so high that they have
no option but to fire at the last moment. Firing for longer would result in
the rocket going back up, it can't hover.

------
dperfect
As if this weren't impressive enough already, according to a comment made by
Scott Manley[1] it sounds like the final maneuver (where it appears the rocket
is making a fairly strong lateral correction) is entirely intentional. Not
sure if anyone here can confirm or deny the claim, but apparently the
trajectory prior to landing is not supposed to be exactly above the barge as
one would expect - I understand it may be an attempt to limit exposure/damage
to the barge in case of failure.

[1]
[https://www.youtube.com/watch?v=C9I55o8hQgs](https://www.youtube.com/watch?v=C9I55o8hQgs)

~~~
Shivetya
just the fact they can hit a barge after falling back from space impresses me.
I wonder if there are any islands they could use instead, surely they had to
have looked for one. Would a stationary oil platform work better?

~~~
noselasd
They do launches with different trajectories, so you'll run out of fuel if the
landing site is fixed and you're launching the rocket in another direction.
Besides, you'll anyway need something to transport it back to mainland.

If all this goes well though, the intention is to eventually fly it back and
land it on the mainland.

------
grecy
Elon says it's in slow motion too

"High resolution, color corrected, slow motion rocket landing video
[https://youtu.be/BhMSzC1crr0"](https://youtu.be/BhMSzC1crr0")

[https://twitter.com/elonmusk/status/588463193070022656](https://twitter.com/elonmusk/status/588463193070022656)

~~~
monk_e_boy
How high did it get? Does it burn the whole way down (I assume it uses those
little X-wings to 'fly down?) When does it start the descent burn? How fast is
it going at this point? How much does it weigh, what sort of forces are we
talking about? How hard is landing this puppy in terms of human achievement?
Top 10% of tricky things humans have so far achieved?

[edit] wouldn't it be easier to hover it a few meters above land and grab it
with some big robot arms?

~~~
sfeng
It burns three times after the second stage detaches. The first is to get the
landing zone closer to the takeoff, the second slows it down from 1300 m/s to
about 250 m/s, the third slows it to (hopefully) 0 m/s on the landing pad.
Here's a diagram:
[http://media2.s-nbcnews.com/i/newscms/2014_51/812491/141217-...](http://media2.s-nbcnews.com/i/newscms/2014_51/812491/141217-launchprofile_f4fcb1ed474952c078a75c07a96cae6f.jpg)

If the 'x-wings' are what I think you're referring to, they're the landing
legs. They are shaped like that to have as minimal impact on the air
resistance of the ascending rocket as is possible. They open just before
landing.

It can't hover. Even just using a single one of the nine engines, the engine
can't be throttled down enough for the rocket to hover. The landing method
relies on what they call a 'hover-slam', where they fire the engine during
landing to slow it down just before it touches.

Landing this is extremely impressive. It is going four times faster than the
speed of sound, and they are landing it on a pad smaller than a football
field. Vertical landing of a returning rocket has never been done. It's also
the key step in the process of dramatically lowering the cost of spaceflight
which could usher in a new era of technology around earth, and on other
planets.

~~~
69_years_and
What's the difference between the tests on earth (as seen on youtube etc)
where the engine runs the whole time and seems to display good throttle
control and this type of landing?

~~~
Two9A
The Grasshopper tests had a full tank of fuel and (if I recall) additional
ballast, to counteract the thrust of the engines. That's what allowed them to
hover and perform the various low-velocity translation tests.

Of course, these barge landings are the first high-velocity tests, so there'll
be kinks to work out.

~~~
69_years_and
Thanks, that would explain that.

I was impressed by how small the barge looked compared with the F9 it's clever
that the F9 can autonomously target such a small area. If they keep targeting
'Just Read the Instructions' by the time land based landings come to be it
will be nailed. Awesome stuff!

------
zaroth
It was jaw dropping as-is, but when they finally do stick a landing I imagine
the engineers will be running around like little kids screaming with the pure
joy and exhilaration of it all. I hope they share the video at mission control
as well when the day does come!

The sheer drama of how fast it comes down, the awesome power of the Merlin
engine just blasting away delta-v... I wonder how many g's it takes on that
final burn?

Would a drougue have simply added too much weight or too much complexity to
deploy? I guess slowing down the freefall velocity before the burn just
doesn't really help all that much?

Amazing that Falcon Heavy will have _27_ Merlins on board.

~~~
jccooper
A drogue would seem unnecessary; a Merlin can scrub off plenty of m/s real
fast, and if it can't do it fast enough, they have more of them. In fact, it
might be easier if the thing is coming in faster, because you get to run the
engine a bit longer and have more time to adjust your aim with the engine's
greater control authority.

Anyway, they don't seem to have any problem managing the vertical velocity.
It's been the horizontal each time. And this time, only a tiny bit off.

------
staunch
The best part of their reusable rocket project is how incremental the progress
has been. I'm not sure I would have appreciated the difficulty of what they're
doing _as much_ without these failures.

~~~
bane
Even cooler is how they're pulling off these tests on production flights.

~~~
jozzas
Getting paid to develop product features is the best way to do it!

~~~
calinet6
A ton of lessons here.

If you deliver your primary objectives well and keep improving at everything
else in the process, your customers will keep on loving you for it.

------
corywright
This is an "unpublished video" on a non-SpaceX YouTube channel. Who uploaded
this?

~~~
palebluedot
From reading the comments over on /r/spacex, this looks to originally have
been an unlisted video in SpaceX's youtube channel, and shortly after
appearing on reddit it was made private. Not before several people had made
copies, however, and re-uploaded it (one of those people has the same reddit
username as the youtube channel linked here).

That said, impressive video. This shows how close they are truly getting.

Unfortunately, it doesn't stop clickbait headlines that imply that this was a
setback (for a while, drudgereport was running a story with the headline akin
to "SpaceX rocket fails to land on landing pad"). Maybe that is why the video
was made private, out of fear of appearing like a failure.

Of course, now that the cat is out of the bag they are better off embracing
the video.

~~~
agumonkey
According to a comment from a collaborator of Musk, saying they dealt with
larger public distrust before, clickbait headlines won't make a difference to
Musk and his team. I'm sure they'll get through with this one.

------
filvdg
this footage give a real sense of how close they are to getting it right

~~~
waterlesscloud
Watching it made me realize I only had an abstract idea of how difficult it
was to even attempt this. It's insanely hard, and they're so close!

~~~
31reasons
Yes its a very hard problem but what makes it hard ? Is it engineering of the
components, algorithms or expensive tests and economics of it ? Maybe people
before Elon Musk were not interested in solving this problem not because its
technically hard problem but because their existing business model is much
more lucrative.

~~~
jccooper
From a technical standpoint, it's tough. You've got big expensive machinery
that operates at or past any reasonable limits in extreme conditions and
moreover gets destroyed with every test if you make the slightest mistake. I
know that when I end up with an iteration interval of an hour it seems like
development takes forever. SpaceX is able to test, what, every couple months?

But the economics is probably more important. The incumbents have such sky-
high development costs that reusability seemed like an impossible task to do
economically. Last time anyone tried they came up with STS, which was highly
capable but ultimately dangerous and ruinously expensive. A new reusable
system seemed like it would take half a trillion dollars in development, and
would probably never have the flight rate to make it worthwhile. Elon thought
that he could do it better. NASA believes designing a reusable system would be
too expensive for them. They're probably both right.

------
Udik
Come on people, have a go at it yourselves:

[http://moonlander.seb.ly/](http://moonlander.seb.ly/)

~~~
Veratyr
Or even better:

[https://kerbalspaceprogram.com/](https://kerbalspaceprogram.com/)

------
Rapzid
I wonder what happened there. Looks at 4 seconds the guidance system figured
it needed to pull an ultra manoeuvre to slow the the horizontal speed(was
drifting left) but ended up with a solution putting the rocket upright again
at nearly 0m. If it would have left some altitude for stabilizing I think they
would have had it.

Arm chair rocket science is fun.

~~~
TeMPOraL
According to Elon's tweet that seems to have disappeared by now, they had
static friction in bipropellant valves introduce a lag that the control system
couldn't handle.

~~~
shostack
Can you or someone else please explain what that means in slightly less
technical terms without dumbing it down too much?

~~~
TeMPOraL
A control system is a feedback loop that connects measurements (orientation,
speed, acceleration) and steering (grid fins orientation, engine power and
gimbaling, RCS/other means of attitude control) in order to steer the entire
system into a desired state (in this case, upright orientation and 0m/s
velocity exactly at the point of touchdown). The control system measures the
state of the rocket and _directly_ adjusts the control inputs - i.e. it's not
a series of if-else instructions, but more like "engine_gimbal_x = P * yaw + I
* integral(yaw) + D * dyaw/dt"[0] - the inputs and outputs are wired together
through a set of mathematical transformations.

The "lag" is a delay between your steering signal and the state of the system
changing in response. In this case, because of static friction, valves
controlling fuel flow reacted with delay (I'm not sure if they're talking
about Merlin's valves or attitude control engines though) - so the rocket did
not react immediately after being told to do so.

There's a whole math field around that topic, known as "control theory". There
are ways to determine the limits of inputs and outputs that will allow your
control system to keep everything in the desired state. In this case however,
the input lag wasn't accounted for and it pushed the system out of the space
of stable states, beyond the ranges where the control unit could keep up with
the changes, so it ended up oversteering. Fortunately, in this case it's
mostly a software problem, i.e. they could tweak the controller to deal with
the lag.

The best way to imagine it is to recall your first experiences with a bike or
ice skates - trying to balance yourself on them is exactly the kind of thing
the rocket was doing, probably with similar results.

My control theory is a bit rusty nowadays, but I hope this clears up some
things.

[0] - if you ever hear about "PID controller", this is exactly where the name
comes from - proportional, integral, derivative.

~~~
shostack
This was exactly what I was looking for. Thanks for taking the time to go into
this level of detail.

So looks like if they can solve for modeling this latency (likely a software
problem), there's a decent shot they'll nail it the next time around?

~~~
TeMPOraL
If this turns out to be the only problem then yes, they have a decent chance
of doing a proper landing the next time around.

------
shiftpgdn
Why did it explode in such a dramatic fashion? I thought the booster was
almost entirely empty when it returns to the barge.

~~~
nickff
There is always some extra fuel and oxidizer, as it is used to slow the
vehicle, and is needed until touchdown. If the vehicle were to run out of
propellant before landing, it would crash. In addition, the LOX makes any
combustion spectacular.

~~~
melling
Complete destruction is obviously expensive. Finding a way to prevent an
explosion if it falls over after landing seems worthwhile.

If it hovered for 5 seconds at .5 meters, for example, could it burn off
enough extra fuel?

~~~
cryptoz
> If it hovered for 5 seconds at .5 meters, for example, could it burn off
> enough extra fuel?

The Falcon 9 cannot hover. The thrust of the single landing engine, even when
throttled down to minimum, will provide significant lift to the empty rocket.
That's part of what makes this maneuver so difficult and so awesome: it's
called the hoverslam, where you achieve 0m altitude and 0m/s velocity at time
= 0.

For reference, though, the Grasshopper/F9R-dev1, could hover due to it only
having 3 engines, not 9, and because they could ballast it with additional
fuel.

~~~
TeMPOraL
> _it 's called the hoverslam, where you achieve 0m altitude and 0m/s velocity
> at time = 0_

Also known as making a "suicide burn", at least in the KSP world.

------
mladenkovacevic
It must be amazing working in a field where failure is almost as exciting as
success.

What's the main obstacle to slowing down and stabilizing the rocket on its
descent to the platform? Is it just a matter of speed or also the shape of the
rocket and its center of gravity? Would a set of 3 parachutes might slow it
down a little bit or at the very least straighten it before the rockets need
to kick in saving some fuel?

~~~
jccooper
SpaceX seems to be able to stabilize fine with RCS and/or their grid fins. The
rocket design must be reasonably stable--even tail-first.

I don't think incoming velocity is much of a problem. Terminal velocity is
gonna be no more than 90 m/s. The engines on that stage are more than capable
of slowing it down--and fast. In fact, they're too powerful--it can't hover.

~~~
mladenkovacevic
If it's a matter of control then all it needs is just a bit more fine tuning.
My money is on success next time they try it.

------
ufmace
Anybody know anything about the tech they're using to guide the stage to the
barge? Since the flight is so short, I suppose they could get a GPS position
on the barge at liftoff and pre-program that as the initial target, but I'd
think they need some kind of terminal guidance actually tracking the barge to
hit it reliably. Maybe visual or radar, or a radio beacon or something?

~~~
grecy
On the live feed, just after +1:30 I heard "Recovery platform has acquisition
signal"

------
grecy
We know it does three separate burns while coming back down (Boostback, entry
burn, landing burn).

I wonder if each burn starts with the RCS thrusters to turn the stage "nose
up".

i.e. when it's free falling, does it always roll around and fall nose down,
requiring RCS to get it back to nose up?

It would be awesome to see footage from the entire return trip. Do they have
cameras mounted on stage 1?

~~~
rdoherty
From what I've seen there are vanes on the top that guide it down, keeping it
upright during reentry and descent.

[http://images.gizmag.com/inline/crs-5-crash-5.jpg](http://images.gizmag.com/inline/crs-5-crash-5.jpg)

~~~
cfreeman
They're called grid fins:

[http://en.wikipedia.org/wiki/Grid_fin](http://en.wikipedia.org/wiki/Grid_fin)

I believe they are less to "keep it upright", but for better accuracy. The
rocket doesn't really having a hard time staying upright because all of the
weight is on the bottom where the engines are.

------
socialist_coder
Is there a reason you couldn't have things on the side of the landing pad that
"grab" onto it and secure it?

It could be as simple as a huge ring of cable that just closes around the top
of the rocket, then pulls it tight on all sides- like the guidelines on a
tower to keep it stable.

Maybe they don't want to do that because they think they can do it without it?

~~~
TeMPOraL
> _Maybe they don 't want to do that because they think they can do it without
> it?_

If they master vertical landing without external support equipment, they can
pull it off on Mars as well. I think that's their other goal here.

~~~
NamTaf
That's certainly the case. It has to be entirely self-contained to the rocket.

------
swamp40
What happens once it lands successfully?

Won't one stray wave tip it right over into the ocean?

Those landing struts are only 1/10 the length of the rocket.

If this wasn't so tall, it wouldn't be nearly the problem that it is.

Are they perhaps really trying to develop a Dragon landing system?

And using this extra tall rocket as a worst-case scenario?

~~~
Osmium
I'm not an expert, but here's my understanding:

> What happens once it lands successfully?

It becomes a lot easier to get permission to attempt a landing on dry land.
But, as I understand it, they will always need to land some rockets at sea. In
the long run, they hope that they can then re-use the rocket, which will
drastically reduce the cost of launches.

> Are they perhaps really trying to develop a Dragon landing system?

They almost certainly are, but this is unrelated to that, I believe.

> And using this extra tall rocket as a worst-case scenario?

No. The length of the rocket is ultimately determined by the amount of fuel it
needs to carry. The first stage will always be very long like this. Note that
this rocket came from a successful mission which launched a Dragon capsule to
the ISS on a re-supply/science mission.

~~~
smackfu
>But, as I understand it, they will always need to land some rockets at sea.

Yeah, this is something I didn't realize. Flying back to land requires fuel,
which cuts into the payload capacity. If a payload is too close to capacity, a
sea landing may be the only option.

------
trurl
"Just Read the Instructions"? Sounds very Culturey.

~~~
TeMPOraL
That's straight from Banks. As is the other barge, that is to be named "Of
Course I Still Love You".

[http://www.tor.com/blogs/2015/01/elon-musk-iain-m-banks-
just...](http://www.tor.com/blogs/2015/01/elon-musk-iain-m-banks-just-read-
the-instructions)

------
peeters
Anyone know how fast the engine's gimbal is? The video makes it look like the
gimbal lags significantly behind the angle of the rocket, so even when you're
rotating one way, you end up burning more toward that angle as the engine
slowly gimbals to the other side.

Granted, this is in slow motion. I just would've expected the engine to be
gimballing to the other side even before there was a noticeable rotation.

------
jordanthoms
It's interesting to think that if you are building rockets, up til now you've
never really gotten to take the rocket apart _after_ flying it - it's burnt up
in the atmosphere or at the bottom of the ocean somewhere. I imagine there
will be lots of interesting insights that come out of recovering, undamaged, a
flown first stage and taking it apart to see what's experienced wear etc.

~~~
vinkelhake
NASA has been recovering their rockets from ocean landings for some time.

See:
[https://www.youtube.com/watch?v=Gbtulv0mnlU](https://www.youtube.com/watch?v=Gbtulv0mnlU)

~~~
TeMPOraL
But only after getting them totally messed up by salt water. Also, those were
solid-fuel rockets, which are significantly simpler than liquid-fuel ones.
There's probably a lot to learn from an undamaged liquid-fuel first stage that
went to space.

------
hurin
Question: Why don't they land into the water instead of a hard surface?
(Wouldn't this give them more leeway in terms of impulse?)

Edit: i.e. landing on a net stretched (under the lake/ocean-surface) by 3 or 4
ships - reel the net it in to raise stage out of the water, I'm pretty sure
seawater is _not_ significantly corrosive from 2-3 hours of exposure.

~~~
ZoFreX
The eventual goal is to land it on land, they're only doing water landings
right now due to the high chance of failure. In the future, the first stage
will land back at the rocket pad, which massively reduces the logistics for
re-using it.

There's a cool mock-up video of what that might look like:
[https://www.youtube.com/watch?v=4Ca6x4QbpoM](https://www.youtube.com/watch?v=4Ca6x4QbpoM)

~~~
hurin
So you're saying the real cost-savings don't kick in until you're landing it
back on the pad, hence salvage from sea is only important as far as perfecting
the technology?

~~~
benihana
Yep. They're doing it at sea because they're in the late alpha stage of this
reusable program.

------
solve
Seems that the control system only tries to guide it on the X & Y axis, but if
I was controlling it and saw it coming in at that steep angle, I'd fire hard
on the Z axis to try to raise it up, fix the angle, and then lower it down
again.

Is it correct to say that this landing control system never tries raising the
craft vertically?

~~~
grecy
It's tricky because it can't hover, one engine on minimum provides too much
thrust.

So if you do raise it up, you'd have to stop the engine, then wait a little
and re-light it again.. which I think is tricky to do, and the engines only
have so many "re-light" cycles in them, so you don't want to use up too many ,
else you can't re-use the thing for another real flight.

------
ezegolub
If any of the engines has a TWR above one when landing, even at it's lowest
setting, i can't help but wonder why don't they use a smaller engine which can
be more effectively used to land.

I'm sure theres a perfectly good reason for this, there's a reason SpaceX has
its reputation, but i'm curious as to why.

~~~
sfeng
For one, developing reliable rocket engines takes a long time, you can't just
whip up a new one. The current Merlin has a very large throttling range
already when compared to existing engines. The size of the engines they use
now is defined by the need to get payload's to space, the landing has to be
secondary.

~~~
simonh
Grasshopper was able to hover, or even perform a powered descent and was
probably lighter than an F9 first stage, so I don't think this can't be it.
They likely do have an engine configuration capable fo a lower minimum thrust,
but they're choosing not to use it presumably because it's not optimal for the
primary mission, and they believe it's not necessary for the landing.

------
magic5227
I almost think it would be easier to let it do what this video shows, and
build a giant metal net to just prevent it from sinking. Or is that harder
than landing on a small platform?

~~~
mb_72
My thoughts too, but I guess any ingress of sea water makes it necessary to
junk the engines. Also, once you've solved the 'landing problem' once,
presumably the method can be reused on each and every subsequent landing; if
you are looking at many such landings it becomes worth doing it 'once' and
properly.

~~~
TeMPOraL
> _if you are looking at many such landings it becomes worth doing it 'once'
> and properly._

Yup; the point is, SpaceX is not trying to just _recover_ the first stage,
they're trying to solve the vertical-landing of rockets for rapid reusability
- which is vital not only for cost reduction, but for their plans to go to
Mars. Because if they solve landing here, they can use the very same technique
to land on Moon, Mars and other planets.

------
bane
Pretty inspiring after all this time that the problem is not so much getting
stuff up, but landing it successfully. I kind of feel like this is where we
should have been in the 70s.

~~~
jfoutz
Pretty sure the original plan was mars after the moon. The cold war shifted
away from the space race, and we built skylab instead. Some of the mars plans
were pretty crazy. send 3 rockets. 1 with crew and supplies, 2 for the return
trip. 2 just in case something went wrong.

------
lotsofmangos
I wonder if you could put thrust deflectors on the legs, then vary the fold
out to help stabilise it just before landing.

------
agumonkey
Someone on ArsTechnica said it was a sticky valve causing thrust lag and
trajectory swing.. anyone thought the same ?

------
paulddraper
That's tricky stuff.

What was the intention behind not doing a water landing, like with the Space
Shuttle boosters/tank?

~~~
scott_karana
I think the plan is to eventually land it somewhere that it can be checked,
refueled, and sent straight back to space.

The barge, I suspect, is simply for safety/liability at this point ;)

(Even if I'm dead wrong, and they want to land it on a barge forever: seawater
is some nasty, corrosive shit that I wouldn't want my rocket dunked into! :)

------
DannoHung
Such a bummer! So close. Keep it up guys, you'll get it soon!

~~~
atroyn
That's two for two for getting to the ship, definitely not a bummer!

------
ezegolub
Any info on how much damage the barge took from that explosion?

~~~
sheerun
"Droneship is fine. No hull breach and repairs are minor. Impact overpressure
is closer to a fast fire than an explosion."

[https://twitter.com/elonmusk/status/588490238936240129](https://twitter.com/elonmusk/status/588490238936240129)

------
rtpg
this might be a silly question but why can't they use parachutes? wouldn't a
mostly empty rocket float? or is there an issue with the salt water and
whatnot

~~~
MrSourz
They intend for it to land on land in the future, not out at sea. For that
they cannot use parachutes.

------
obituary_latte
Was this filmed from a drone? I couldn't find any info.

~~~
tommoor
In the middle of the ocean It seems doubtful... I'm also intrigued by the
angle - maybe a helicopter?

~~~
obituary_latte
Plausible it could be launched from the landing platform prior to the attempt.
Although, you'd think a drone could have a closer viewpoint. Anyway, very cool
to see.

------
dude3
It looks like the main engines didn't cut quick enough.

------
natarius4k
Makes me wonder if they just leave them on the ground of the ocean or recover
them?

...I bet otherwise the Russians or Chinese would love to get their hands one
of them :)

~~~
31reasons
Chinese are just waiting until it succeeds. Their hackers are probably on
stand-by to download the blueprints and the code. lol

------
transfire
Its tail is wagging way to much. Landing will always be a crap shoot if they
don't get that stabilized.

~~~
TeMPOraL
You mean thrust vectoring? It's intentional, it's how the rocket steers
itself.

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transfire
You mean it's not pixie dust? ;-P

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TeMPOraL
Naah, pixie dust is what the rocket is covered with before launch; you can see
it falling off during lift-off. Check out the launch videos. ;).

