5 ms·

If it sounds too good to be true, it usually is. Spinlaunch: BUSTED!: https://www.youtube.com/watch?v=9ziGI0i9VbE https://www.youtube.com/watch?v=9ziGI0i9VbE S

If it sounds too good to be true, it usually is. Spinlaunch: BUSTED!: https://www.youtube.com/watch?v=9ziGI0i9VbE https://www.youtube.com/watch?v=9ziGI0i9VbE Spinlaunch: BUSTED (Part 2): https://www.youtube.com/watch?v=ibSJ_yy96iE https://www.youtube.com/watch?v=ibSJ_yy96iE

Robotbeat 5y ago
Man, I have my opinions on Spinlaunch, too, but I find thunderf*t’s videos (especially the BUSTED ones) unenlightening & unhelpful to rationally discussing the pros and cons of some technology. Scott Manley’s video (if video is the format you prefer) on Spinlaunch was much better. Scott Manley also has a much better understanding of rockets and space technology than thunderf*t. https://youtu.be/JAczd3mt3X0 https://youtu.be/JAczd3mt3X0
- GuB-42 5y ago
  Thunderf00t can show great science at times, but most of his channel is just opinion pieces disguised as science. Most of his arguments are sound, which is not very difficult considering some of the things he attacks, but some are more debatable, or even just wrong. And he never back down, and he has a community of mindless followers which is more fitting to a cult leader than to a man of science.
  - heyflyguy 5y ago
    His analysis of trajectory (the shadow of the missile against the terrain) was laughable.
- NikolaeVarius 5y ago
  Thunderf00t is a contrarian with a cult audience.
cjensen 5y ago
The tumbling in this video is a good demonstration of the angular momentum problem. The projectile has a carp ton of angular momentum after release, and there's no system in place to fix that. Maybe you could cancel it using the atmo and aerodynamics except that would probably melt the fins. And angular momentum is just one of the challenges that appear to be unsolvable. When you hit orbital height, your velocity is in the wrong direction. How do you add enough horizontal velocity? How do you construct a rocket engine that can survive the forces involved in initial launch? How do you prevent the bearings from melting? How do you construct a launch chamber which survives the explosive compression when the projectile penetrates the vacuum barrier into the atmo? And all with a Theranos-level of founder knowledge.
- NovemberWhiskey 5y ago
  >The tumbling in this video is a good demonstration of the angular momentum problem. The projectile has a carp ton of angular momentum after release I'm not sure I follow; if the object is held rigidly to the launch arm until the point of release, it's going to have a lot of angular velocity, sure, but that doesn't imply rotation, does it?
  - andechs 5y ago
    The object is not a point mass at the end of the arm, it's a line. Different parts of the line are moving at different relative velocities & accelerations relative to the centre of rotation, and thus when released the rocket not going to go straight.
    - NovemberWhiskey 5y ago
      But if the object is rigid, and the acceleration is through its center of mass, then there isn't any rotational component, right?
      - feoren 5y ago
        GP has a point: consider the limiting case of an extremely long payload on an extremely short centrifuge arm. The payload is basically rotating around its own center of mass already, before release. Put your left index finger on the middle of your right arm, rotate the whole thing, and release -- you'll intuitively see that your right arm must keep rotating. But see my other response above -- this does not seem like one of the bigger issues when the centrifuge arm is much longer than the payload. And we already know this launch system will only ever work for small, non-human, durable payloads.
        NovemberWhiskey 5y ago
        >GP has a point: consider the limiting case of an extremely long payload on an extremely short centrifuge arm. The payload is basically rotating around its own center of mass already, before release. But isn't the payload rotating around its own center of mass because the centripetal force acting on the "front" of the payload is not parallel with the centripetal force acting on the "rear" of the payload? As soon as you cease to apply the centripetal force (i.e. release the projectile) you're no longer going to generate any torque. Imagine the payload being held by ropes on the back and on the front and then both ropes releasing exactly as its center of mass passes through horizontal.
gremloni 5y ago
Thunder started out great but now he just likes to rationalize the dominant perspective. It’s a loss.

Robotbeat 5y ago

Man, I have my opinions on Spinlaunch, too, but I find thunderf*t’s videos (especially the BUSTED ones) unenlightening & unhelpful to rationally discussing the pros and cons of some technology. Scott Manley’s video (if video is the format you prefer) on Spinlaunch was much better. Scott Manley also has a much better understanding of rockets and space technology than thunderf*t. https://youtu.be/JAczd3mt3X0 https://youtu.be/JAczd3mt3X0

GuB-42 5y ago
Thunderf00t can show great science at times, but most of his channel is just opinion pieces disguised as science. Most of his arguments are sound, which is not very difficult considering some of the things he attacks, but some are more debatable, or even just wrong. And he never back down, and he has a community of mindless followers which is more fitting to a cult leader than to a man of science.
- heyflyguy 5y ago
  His analysis of trajectory (the shadow of the missile against the terrain) was laughable.
NikolaeVarius 5y ago
Thunderf00t is a contrarian with a cult audience.

cjensen 5y ago

The tumbling in this video is a good demonstration of the angular momentum problem. The projectile has a carp ton of angular momentum after release, and there's no system in place to fix that. Maybe you could cancel it using the atmo and aerodynamics except that would probably melt the fins. And angular momentum is just one of the challenges that appear to be unsolvable. When you hit orbital height, your velocity is in the wrong direction. How do you add enough horizontal velocity? How do you construct a rocket engine that can survive the forces involved in initial launch? How do you prevent the bearings from melting? How do you construct a launch chamber which survives the explosive compression when the projectile penetrates the vacuum barrier into the atmo? And all with a Theranos-level of founder knowledge.

NovemberWhiskey 5y ago
>The tumbling in this video is a good demonstration of the angular momentum problem. The projectile has a carp ton of angular momentum after release I'm not sure I follow; if the object is held rigidly to the launch arm until the point of release, it's going to have a lot of angular velocity, sure, but that doesn't imply rotation, does it?
- andechs 5y ago
  The object is not a point mass at the end of the arm, it's a line. Different parts of the line are moving at different relative velocities & accelerations relative to the centre of rotation, and thus when released the rocket not going to go straight.
  - NovemberWhiskey 5y ago
    But if the object is rigid, and the acceleration is through its center of mass, then there isn't any rotational component, right?
    - feoren 5y ago
      GP has a point: consider the limiting case of an extremely long payload on an extremely short centrifuge arm. The payload is basically rotating around its own center of mass already, before release. Put your left index finger on the middle of your right arm, rotate the whole thing, and release -- you'll intuitively see that your right arm must keep rotating. But see my other response above -- this does not seem like one of the bigger issues when the centrifuge arm is much longer than the payload. And we already know this launch system will only ever work for small, non-human, durable payloads.
      - NovemberWhiskey 5y ago
        >GP has a point: consider the limiting case of an extremely long payload on an extremely short centrifuge arm. The payload is basically rotating around its own center of mass already, before release. But isn't the payload rotating around its own center of mass because the centripetal force acting on the "front" of the payload is not parallel with the centripetal force acting on the "rear" of the payload? As soon as you cease to apply the centripetal force (i.e. release the projectile) you're no longer going to generate any torque. Imagine the payload being held by ropes on the back and on the front and then both ropes releasing exactly as its center of mass passes through horizontal.

gremloni 5y ago

Thunder started out great but now he just likes to rationalize the dominant perspective. It’s a loss.