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Panasonic Lumix Nueva es una cmara Serio Con un modo Autofoto
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Qu son los Puntos Cunticos, y para qu lo quiero en mi TV?
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The Ultimate Sports elctricos del coche est a slo 4 pies de
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Blogs Cientficos
Pueden Contar araas?
Islandia: La Tierra real de fuego y hielo
Los autores de la isla en el fuego responder sus preguntas sobre
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Dot Fsica
Por qu es tan difcil de conseguir un cohete?
Por Rhett Allain 01.19.15 |
09:41 am | Permalink
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20/1/2015 Por qu es tan difcil de conseguir un cohete? |
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Despus de lanzar con xito una cpsula de reabastecimiento, el
SpaceX Falcon 9 cohete intent aterrizar en una barcaza en el ocano.
Como se puede ver, el intento deaterrizaje no tuvo xito. En
realidad, deberamos sorprendernos? Me sorprende que el cohete
estaba tan cerca de llegar a aterrizar en absoluto. Aterrizaje de
un cohete como estees bastante difcil.
As que, por qu es este cohete difcil a la tierra? Antes de dar
una explicacin, permtanme darles un recordatorio. Soy un fsico y no
un cientfico de cohetes. Voy a hablar delos principios de la fsica
en general y no detalles tcnicos del aterrizaje de cohetes.
Lunar Lander es fcil
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S, aterrizamos varias naves espaciales en la Luna con el mdulo
de aterrizaje lunar en las misiones Apolo.
Imagen: NASA. El Lander lunar de la misin Apolo 16.
En realidad, esto tambin est el famoso juego de arcade llamado
Lunar Lander. Aqu es una versin en lnea si quieres jugarlo . El
objetivo es cambiar el ngulo y empuje para un
mdulo de aterrizaje aterrizar con seguridad en la luna.
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Captura de pantalla de Lunar Lander juego en Phet.
Ok, el verdadero juego Lunar Lander no siempre es tan fcil -
pero es ms fcil que el aterrizaje de la SpaceX Falcon. Cul es la
diferencia? El mdulo de aterrizaje lunar tiene
un cohete en la parte inferior, pero gira con otros propulsores
en el lateral. El Falcon 9 tiene un motor de cohete en la parte
inferior y utiliza este cohete tanto para empuje yrotacin. Esto
hace que el Falcon 9 un poco ms difcil de maniobrar (tambin el
mdulo de aterrizaje lunar fue, ya sabes, la luna - donde el campo
gravitacional es ms pequeo).
Tres Propuestas de Rocket
El cohete Falcon 9 se puede hacer tres cosas diferentes con el
propulsor principal:
Aceleracin vertical: esto es til para cosas como ralentizar
decente por lo que no, ya sabes ... accidente del cohete.
Aceleracin horizontal: se utiliza para cambiar la velocidad
horizontal del cohete. Esto es muy til para el cambio de la posicin
horizontal del cohete para que puedaaterrizar en una barcaza en el
ocano.Aceleracin angular: esto cambia el movimiento de rotacin de
la nave espacial sobre su centro de masa. Esto sera til si desea
asegurarse de que el cohete cay en unaposicin vertical.
Tal vez esto tendr ms sentido con un ejemplo rpido. Supongamos
que el cohete Falcon viene en un aterrizaje y tiene cierta
velocidad horizontal. Con el fin de reducir lavelocidad para un
aterrizaje seguro, el cohete debe empujar en la direccin opuesta.
Esto es lo que sucede.
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A fin de acelerar a la derecha, el cohete ngulos de un poco para
que apunte a la derecha. Sin embargo, ya que esta fuerza de empuje
no acta en una lnea que pasa por elcentro de masa, hay un par de
torsin sobre la nave espacial que cambia su movimiento de rotacin.
Aadir en la parte superior de esta el hecho de que hay que cambiar
tambinel valor de empuje con el fin de acelerar el cohete hacia
arriba y abajo tambin.
Es un problema bastante difcil de conseguir un cohete como este.
En realidad, se puede intentar algo como esto por s mismo. Obtener
una escoba o un palo largo y cabeza fueraen el que no se llegar a
nada. Ahora trate de caminar mientras equilibra la escoba en la
mano con slo colocar el extremo de la escoba en la mano. Cmo dejar
de caminar? Heaqu un ejemplo.
Image: Rhett Allain
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S, en este ejemplo yo me detuve en efecto la escoba y no me
caigo encima. Sin embargo, con el cohete que necesita tanto parar
en Y mantenerlo vertical en el extremo.
Por qu no utilizar un Diseo Rocket diferente?
Esto es pura especulacin, pero permtanme considero dos diseos de
cohetes. En primer lugar, existe la Falcon 9. En segundo lugar, hay
un diseo ms plano que sera ms fcila la tierra. Se vera algo as como
el mdulo de aterrizaje lunar.
Este "Easy Lander" sera mucho ms fcil de controlar. En primer
lugar, no es alto y delgado como los Falcon 9. El centro de masa es
mucho ms cerca de los principalespropulsores para que no ejerceran
tanto torque para cambiar el movimiento de rotacin. Adems de eso,
hay varios propulsores para que usted pueda variar el empuje
para
crear par nulo si queras. Finalmente, este diseo tambin tiene
propulsores laterales. Usted puede cambiar el movimiento horizontal
de la Fcil Lander sin siquiera girar la naveespacial. Parece como
un cohete mejor, no?
Aunque el Easy Lander sera ms fcil a la tierra, no sera tan
bueno como el Falcon 9. El Falcon 9 no est diseado para aterrizar
en una barcaza en el ocano. No, est
diseado para lanzar una carga til en rbita. Esa es su funcin
primaria, una funcin que el Easy Lander hara un trabajo muy pobre
en. Los cohetes son alto y flaco como ellosson tan que tendr una
carga de aire inferior en l, ya que acelera a travs de la atmsfera.
Cuanto menor sea el rea de la seccin transversal de la parte
frontal del cohete, menores la resistencia del aire. Si el Easy
Lander fuera a lanzar una carga til al espacio, necesitara mucho ms
combustible para compensar la resistencia del aire ms grande. Con
msde combustible, lo que se necesita cohetes ms grandes (por la
masa de combustible aumento) que necesitaran an ms combustible.
Cuando se lanza un cohete, cada poco de
los asuntos comunes.
Por supuesto, eso es slo especulacin acerca de la forma de un
cohete. De cualquier manera, creo que todos estamos de acuerdo en
que hacer un cohete lanzar una carga til enrbita y luego de forma
segura de la tierra es una cosa muy difcil de hacer.
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Gerhard a day ago
It's difficult for many reasons, not least being that - as the
article says - the Falcon 9 first stage is designed to lunch things
into orbit, not to be take off and
land again.
It's difficult because trying to keep upright something that's
42m tall (without the legs) and only 3.7m in diameter is a pretty
big ask, not least when you're
trying to do it accurately.
It's difficult, too, when the starting point is at a 50-mile
altitude and the thing you're trying to land is travelling at
3,600mph.
It's also pretty difficult when the steering fins you have on
your rocket have run out of hydraulic fluid and have jammed in a
'hard over' position, making the
aerodynamics rather different to what the avionics systems are
expecting.
To be honest, getting the thing down to relatively small barge
that's parked in the middle of an ocean; and ever-so-nearly getting
the rocket stage to hit the
(Space-) X on the deck is a pretty astounding achievement.
10
Reply
YeahRight a day ago> Gerhard
The Falcon first stage IS designed to land again. If someone
gave you a realistic model of the almost empty first stage with the
correct mass
distribution, you would be surprised how easily you could
balance it on your hand. The tanks have a mass ratio of something
like 50 to 1, so the whole
thing would feel like a thin, tall plastic bottle with a little
bit of liquid in it and a bunch of quarters attached to the
"bottom" end of it.
7
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Reply
Gerhard a day ago> YeahRight
Okay, the rocket has primarily been designed to launch things
into orbit. It's been modified to make it capable of landing again.
That process
has seen several changes made along the way, not least the grid
fins to control roll at hypersonic velocities, something the gas
thrusters
couldn't cope with on the early tests.
Whilst the weight distribution (with empty tanks) makes life a
lot easier for attempting landing, it's by no means an easy task to
put the thing
upright on a designated spot.
2
Reply
YeahRight a day ago> Gerhard
According to Elon Musk the rocket has been designed from the
get-go to land and re-use the first (and maybe) the second stage. I
will
take his word over speculation on the internet about that topic.
That the required design elements are being tested in a serial
fashion
has nothing to do with the intention of the design and the
necessary caution that is required to prevent economic failure of
the company
should the main source of money (the US government) withdraw
because of a failure to meet their goals (which are limited to
ISS
resupply, they don't care about re-use at all). Again, I would
urge you to build a correctly weighted model, then come back to me
and
we'll talk about the "difficulty" to balance it, again. This
design is nowhere close to being top-heavy.
4
Reply
Gerhard 16 hours ago> YeahRight
I really have got better things to do than to build a
correctly-weighted model of an F9 first stage!
I'm not saying anything about the weight distribution of the
stage (which is, effectively, little different to any other similar
first stage).
Reply
YeahRight 15 hours ago> Gerhard
So do I, but at least I have a little bit of physical intuition
left for what's going on here, unlike the author of this piece who
didn't invest a
second of his time in thinking about what exactly he is dealing
with before grabbing his keyboard. The tanks are basically paper
thin
(the only way to build rockets), they are basically empty (at a
mass ratio of one the rocket would still have delta v or approx.
3km/s, far
more than we need to reach the ground in one piece!) and the
heaviest components are the engines (which are at the bottom).
A
physicist needs to know at least this much (this little, really)
about rockets and a physicist who doesn't shouldn't write about
them!
2
Reply
roebling 3 hours ago> YeahRight
The fins are on the wrong end for steering it down. Better if it
flipped at the apogee, shot a balloon out the butt to slow its
descent, and it
steered for a clear spot in the ocean, to be retrieved
there.
Euroranger a day ago
Landing one is easy. Landing it so that it's post-landing
condition allows it to be used again for something more than spare
parts is the tough part. :)
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Reply 9
Reply
Soulxlight a day ago> Euroranger
Landing the rocket isn't so hard (though it still is hard),
landing it where you want it is the hard part.
1
Reply
YeahRight a day ago> Soulxlight
That's also no harder than with a plane or a helicopter.
Actually, it's probably easier than in case of a plane, which has
to land at at given spot
with a given vertical AND horizontal velocity. It's certainly a
lot easier than for the Shuttle, which had exactly one controlled
fall attempt without
any active propulsion.
Reply
Alan Smith a day ago> YeahRight
I disagree. The differential equations of motion for a plane are
much more suitable for optimal control than those of inverted
pendulum.
Also, both the horizontal and vertical motion of the rocket need
to be near-zero upon landing.
4
Reply
YeahRight a day ago> Alan Smith
That's kind of curious, since the complete differential
equations for the motion of a plane and a rocket in the atmosphere
are exactly
the same. Since a plane is usually expected to have an airframe
that can withstand the forces in all possible attitudes (including
upside
down and flying backwards) and since the airframe has less
symmetry than the typical rocket (which is typically cylindrical
with one
moment of inertial being small compared to the others), the
equations are much harder to solve for the general flight
conditions of a
plane than those of the limited ones of the rocket.
In particular the inverted pendulum problem for a rocket can be
linearized because the angles are small, so it really boils down to
a
simple two dimensional harmonic oscillator (at least if we
forget about the rotation around the axis), which can be stabilized
by
choosing controller loop gains and time constants properly. So I
am really surprised that you think that controlling a plane is
easier than
controlling a landing rocket. Would that be because you have
never done either?
Reply
YeahRight a day ago
This is, yet again, the wrong explanation. The center of mass of
the Falcon first stage is low because the engines are much heavier
than the tanks of the
rocket and all of the fuel is located near the lower end of the
tanks. A physicists should know better, by the way, and should have
done his homework. The
video of the walking person balancing a broom stick is
particularly misleading. There are absolutely no forces acting on
the broomstick that are due to a
constant movement. The only forces would be caused by
acceleration and they are well known and can be compensated for.
Stick balancing is an absolutely
trivial circus act. That some clumsy person in an internet video
isn't good at it has zero relationship to the actual physics at
work in rocket science.
9
Euroranger a day ago> YeahRight
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Reply
Everything I learned about how to reply to this I learned via
KSP.
Mun or bust.
2
Reply
YeahRight a day ago> Euroranger
Despite claims to the opposite Elon Musk does not use KSP to
design his rockets. :-)
1
Reply
Asdf Ghjk a day ago> YeahRight
He never said the center of mass is exactly at the middle. And
the stage itself is still pretty heavy, so the residual fuel and
the engines doesn't mean
the center of mass is at the bottom.
Reply
YeahRight a day ago> Asdf Ghjk
The center of mass is not at the bottom but it's not nearly as
high as the illustrations make it appear. The broom example is,
from a physical
perspective, completely misleading (and even then it's a
relatively simple control problem that can be solved in many ways
by a bunch of kids
as a hackathon problem). The real engineering problems with this
have nothing to do with the trivial physics problem mentioned here.
One of
the big ones is the movement of the fuel. Since the first stage
does not have a pressurized bladder, which keeps the fuel supply to
the engines
alive at all times in restartable orbital stages, one has to be
very careful at orienting the rocket stage while it is in
free-fall, otherwise the fuel
might accumulate at the upper end of the tanks before the
engines can be re-started. I think that is what happened the first
few times they tried
this, with the result that the small attitude control engines
could not get the stage into an attitude which would have allowed
re-starting the
main engine (which then produces the necessary acceleration to
collect the fuel at the right end of the tank). Then there is
supersonic friction
leading to heating that evaporates the fuel so fast that the
design bursts like a balloon etc... those are really hard ones. The
slightly elevated
center of mass is trivial.
4
Reply
jotun a day ago
I know you said you just wanted to focus on the physics
principles and not the technical details, but the technical details
make up the overwhelming majority
of the actual difficulty.
The inverted pendulum (broomstick) balancing act is difficult
for humans, but for an electronic or computerized control system
it's a fairly trivial task. In an
ideal world without all the little technical details, the
computer would be able to land on the dot every time and make it
look easy -- like using MechJeb in
Kerbal Space Program.
Here's a neat video of two quadrocopter drones that can not only
balance an inverted pendulum while flying, but can toss it between
each other:
https://www.youtube.com/watch?...
3
dr2chase a day ago> jotun
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Reply
dr2chase > jotun
So clearly, all that we need is two giant quadrocopter
drones....
1
Reply
Flynn Pierce a day ago> jotun
Another day, another step closer to the Manhack.
Seriously though, it amazes me how much progress they're making
with the quadcopters. (I don't know if I'd call it trivial though,
a lot of work goes
into these things)
Reply
derricka4mag 4 hours ago
We can copy nature. Nature already has a system to gently
capture phallic shaped objects that may arrive at imprecise angles.
Yes, what I'm proposing is a
giant inflatable vagina.
2
Reply
roebling 3 hours ago> derricka4mag
Tow it out in the ocean and get out the way...
Reply
neethimesama a day ago
You've ignored the fact that the Falcon 9 first stage has grid
fins at the top to provide some fine steering control, as well as
nitrogen gas thrusters.
Additionally, as others have pointed out, the center of mass is
towards the very bottom of the first stage by the time landing
occurs, since that's where the
heavy engines and remaining propellant are.
The first stage performs 3 burns in order to make a precision
landing: A boostback burn to reverse its direction and send it back
in the direction of the landing
site, a re-entry burn to slow it down as it encounters the
thicker parts of the atmosphere, and a final landing burn just
before touchdown. It doesn't rely on the
rocket engine(s) for steering for the majority of it's flight
back to the landing site. That's done by the grid fins and the
nitrogen gas thrusters. A small amount of
research (also known as journalism) would have revealed these
things.
2
Reply
Rick Papo 9 hours ago
There's one more reason the Falcon rocket is skinny: American
roads. Unlike the Saturn V and certain parts of the Space Shuttle
system, it was designed to
be transported from California to Texas to Florida by a standard
cargo hauler. As such, it could not be made any wider than it is,
or it would have problems at
certain points (underpasses and tunnels) along the way.
http://forum.nasaspaceflight.c...
1
YeahRight a day ago
That the inverse pendulum problem scares a lot of people
(including physicists who don't spend a couple minutes thinking
about it!) is probably due to the
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Reply
That the inverse pendulum problem scares a lot of people
(including physicists who don't spend a couple minutes thinking
about it!) is probably due to the
fact that for an unfortunate choice of parameters the necessary
movements to keep a balancing act going falls into a range of
response times (short) and
motion ranges (very small) that humans are ill-equipped to deal
with. This is especially true for short sticks that many may have
tried to balance for fun. We
are the more astonished when acrobats balance really long poles
with heavy top (e.g. other acrobats!) almost with ease. The actual
physical solution to the
problem is, of course, counterintuitive. The required response
time to keep the pole stable increases with pole length, which
makes balancing long poles
easier than balancing short ones. Acrobats also know that the
proper way to balancing a pole does not involve just a horizontal
but also a vertical movement.
Once can remove the torque that is acting on the pole by letting
it fall a little, a motion which acts stabilizing on its movement
(this is similar to the wire
balancing act, where the correct response of the acrobat is to
lower his center of mass, rather than trying to counteract the
horizontal movement, which sets
the wire in motion even more!).
In short, what looks hard to a human who is trying to balance a
short stick is comparatively easy for an automated control system
that has to balance a
slowly moving building size empty aluminum tube.
1
Reply
Costive a day ago
I am impressed with this technology... I believe it will soon be
functional.
1
Reply
Lionel Bouton a day ago
What makes it even more difficult is that there is probably wind
to account for and this wind might not even be constant. Close to
landing, there are probably
turbulences generated by the exhaust gases too.
During descent you can afford to lean a bit but close to
touchdown you must manage to be at the same time :
* in a vertical position (or at least almost vertical with a
margin depending on your feet position, wind speeds, surface
orientation) or you will fall over,
* having vertical speed below a threshold were you would damage
the bottom of the rocket,
* having horizontal speed below a threshold were you would fall
over.
If you don't meet these conditions at the right time (touchdown)
you will crash.
1
Reply
adamrussell an hour ago
I read somewhere that they ran out of hydraulic fluid.
Reply
Scott Campbell an hour ago
It is at least a partial success as it was in great proximity to
the floating landing site. I am sure they learned a lot and the
next will be completely successful.
No one else has ever attempted this feat!
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Reply
Unlo4 2 hours ago
Not to mention the heaving of the ocean, making your landing pad
a moving target as well.
So why not horizontal thrusters at the top of Falcon to steer
the nose?
Reply
InfinityLoop 2 hours ago
Step 1 - know your audience. Do you have any idea who the
author's
target audience may be? Is it for all of you armchair rocket
scientists, (if you are all so knowledgeable, why aren't you
working for
SpaceX) or for the average Joe that may or may not have a
any
understanding of the physics involved but is interested in the
topic,
and a simplified explanation makes the article readable? You are
not
doing your readers any favor by writing an article in such
painful
detail that causes almost all of your reader's eyes to glaze
over and
they give up after the second paragraph. If you want a
detailed
article, try Science News or any of the 3900 publications
co-authored by
NASA. Step 2 - understand your reason for writing - it is to
inform
and bring enjoyment to your readers, or is it to show off how
much you
think you know? Personally I am pleased that the author takes
the time
to write the articles in the first place, and write them in a
manner
that the average person can understand them. If you are all
so
brilliant, why don't you try to write an article and get it
published?
Its too easy to criticize and much harder to do. This is NOT
a
peer-review publication.
Reply
roebling 3 hours ago
"Why Is It So Difficult to Land a Rocket?" Maybe because they
were designed to go up, not down. Why is it hard to balance a
toothpick on its end?
Reply
aniptofar 4 hours ago
Actually there's not much difference between a rocket descending
or ascending except the control thrust capability and the change in
the center of gravity
(lowering) due to the spent fuel.
Reply
Garland Greene 4 hours ago
One day our civilization will advance to the point where we are
on equal footing with the noble Kerbal people
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Reply
araczynski 20 hours ago
common sense that this design would suck at landing. common
sense would also dictate that if you needed to go ahead with this
design, to then incorporate
some kind of 'legs' protruding/expanding from the bottom third
of the body when reaching a certain threshold, that would then fire
their own reserves of
stabilizing engines.
if we have all these self stabilizing moving devices that can
already compensate for momentum on the fly in order to maintain a
certain orientation, even with
human weight on top of it (i.e. the single wheel motorcycle, or
those side by side wheel scooter things that were supposed to take
over the earth a couple of
years ago) I'm not sure why they wouldn't have bothered to
incorporate something similar.
Reply
Sandra 20 hours ago
Landing the rocket on the moon will be somewhat difficult to
perform. However, it can even be possible in the future with the
help of growing technology.
bit.ly/MoonRegister
Reply
Colin Stein 20 hours ago
with thrust on a rocket coming from its base its at most only
self righting in flight in the opposing direction of boost, once
the thrust gets interrupted there is no
second chance to re-calibrate.
an umbrella can calibrate a touch down because it rights itself
in descent, and a pogo-stick can land and land and land again
because it alleviates the
problem of a rigid landing penetrating a surface (or
catastrophic landing) by reducing its contact force.. ie. what a
landing thruster is potentially doing till it
comes within range of interruption, which then what happens is a
sudden swell of additional force from thrust contact with the
ground causing momentum
alteration, or a sudden no upward force and fall.
just don't let it fall without a mechanism for vertical
orientation in place.. other wise just catch it.
as fascinating as sticking a rocket landing is, a rocket is
neither a gymnast nor a cat
Reply
Shakenbake80 21 hours ago
Why do these threads always turn into "my dick (in this case
knowledge) is bigger (more vast) than yours"?? Everyone's an
expert!
Paul_Scutts a day ago
My thanks to SpaceX for supplying the video of the first landing
attempt upon a solid surface. There are so many variables that need
to be considered both
with the stage, the barge and the general environment. Very
complex, but if anyone can do it, I believe SpaceX can and will.
Forget the economics of re-
usability for anything other than what they are trying to do. I
wish them well.
PS: IMO, the author's use of trying to balance a broom stick in
the palm of the hand, whilst simplistic, effectively conveys the
difficulty of what SpaceX is
trying to do. Well done.
PPS: I am still of the opinion that SpaceX will require some
form of anchoring & momentum absorbing mechanism fired from the
top of the stage upon initial
contact with the deck/ground. Otherwise, I can't see them
pulling it off with any degree of reliability.
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Reply
Pronounce a day ago
Walking is controlled falling. That's hard enough for some of us
when we're easily able to change our shape. Now put yourself in a
solid tube and try to
walking without falling. Sorry, can't be done.
If science can make a tube walk without falling then they can
land a rocket without crashing. I think having a gyroscope would be
the first thing I'd include.
Maybe I'd try something like that robot with one leg that uses a
pogo motion to stay erect.
Reply
Steve Myrick a day ago
I think we need a way to land in a horizontal position with
flotation collar and water tight components to protect from
seawater. That would be a cheaper route.
You could spray the whole outside with polybutylene cheaply.
Landing straight up is too 1950's Buck Rogers stuff. I just dont
see this mode a consistent
system in the future due to the mass. I don't think you could
land a Segway straight up on a barge.
Reply
YeahRight a day ago> Steve Myrick
They are aiming at a turnaround time of hours. The space shuttle
solid rocket boosters had to be refurbished and didn't fly until
months after each
water landing, and the cost of operations was probably higher
than it would have been by manufacturing new boosters from scratch.
Keep in mind
that reducing cost was not the goal of that design by the time
it actually flew.
Reply
Steve Myrick a day ago> YeahRight
It that's the case they will have to add a large tripod footing
system that extends and falls into place right before landing that
will steady the
booster as it touches down. That will turn the landing shape
into a "Triangle" instead of a long narrow tube. A long narrow tube
is just too
complicated to constantly land.
Reply
YeahRight a day ago> Steve Myrick
They have landing legs. The "long, narrow tube" meme is
completely false, anyway, since most of the tube is completely
empty and
very lightweight. At the time of landing most of the relevant
mass is concentrated at the engines and in the bottoms of the
kerosene
and lox tanks. Ideally, at that point there is not much fuel
left, certainly not more than a few seconds worth of a single
engine's thrust at
take-off, which would be, at most, a fraction of a percent of
total fuel mass.
Reply
Steve Myrick a day ago> YeahRight
Its gonna take bigger landing legs than what I see in the video.
I'm talking about legs that are about 1/3 the height of the whole
booster.
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Reply
YeahRight a day ago> Steve Myrick
Well, since you are the expert, maybe you want to show us your
stability calculations? Where is the center of mass of the rocket
and
just how many degrees of tilt do you think the landing legs will
have to cope with on a flat surface?
Reply
Steve Myrick a day ago> YeahRight
Unfortunately I am but a lowly rat catcher and not an expert.
However the size of the landing legs will be an important piece to
this
puzzle.
Reply
P Bone Pickin a day ago
Keeping with the KISS principal, why is the design about landing
upright on a boat? Why not land land in the ocean with flotation
device? As I am not a rocket
scientist, there must be a reason that I do not understand about
why landing upright on a barge it preferable to landing and
floating in ocean (like most US
space capsules had done). Can anyone explain?
Reply
Gerhard a day ago> P Bone Pickin
The aim is to land it at Cape Canaveral, but authorisation to do
that won't be given until it's been proven that it can land safely
somewhere else - and
the barge fits the bill for that.
The barge will also be used for future flights where the payload
requirements are such that the rocket can't carry enough fuel to
return to the launch
site, i.e. landing on a barge downrange will be the only option.
(In those circumstances, it may be refuelled and then fly itself
back.)
Water landings were okay for the shuttle boosters as they pretty
basic (essentially big fireworks), but this has nine engines that
would be wrecked by
immersion in salt water.
1
Reply
EnigmaMaitreya a day ago> P Bone Pickin
I think it has been said the Water Landing is ONLY until the
system proves itself so towns etc are not in danger.
Once the system is proven, and i have no doubt it will based on
the film, then the landings will be at the launch facility.
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