74 votes
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Did a flight controller ever answer Flight with a no-go?

One thing to note is that these polls of the room are largely for-the-record - in other words, if a flight controller was sitting on a problem that would prevent the accomplishment of a major ...
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23 votes
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How does “space weather” cause reaction wheel failure?

Ceramic bearings are a relatively new concept. They were a hot research topic in the late 1970s and didn't become commercially available until the mid 1990s. The Far Ultraviolet Spectroscopic ...
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  • 62.8k
21 votes

How were the pilots of the space shuttle able to operate the rudder after time in space?

Despite the many other (unsourced) answers stating the opposite, this is actually a very valid concern. Not from a physical weakness angle, but rather, even though a shuttle mission was a couple of ...
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17 votes
Accepted

How can a rocket go straight up after ignition?

Rockets can use different systems for attitude control (control thrusters, fins, gyroscopes, TVC, ...). Since you ask for the seconds after liftoff, the relevant system is TVC (Thrust Vector Control). ...
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  • 1,324
17 votes
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Could the Apollo Lunar Module be flown to a landing without the LEM Guidance Computer?

"Could be flown" is a clear yes, "could be flown to a landing" is another story. Most of the points you are listing can be accomplished using the backup system in the LM, the Abort Guidance System (...
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  • 1,941
13 votes

High altitude stage separation

For all modern rockets (and as far as I know, for all rockets ever, since at least the V2), the rocket isn't controlled from the ground, but by electronics (computers, for modern rockets) on the ...
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12 votes

Why does spinning help stabilisation?

This answer answers the title "Why does spinning help stabilisation" rather than specifically for launches. Context Before jumping into the answer it is worth looking at the background. With rigid ...
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  • 8,848
11 votes
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Does this kill vehicle contains momentum wheels? Watch how it moves!

The thruster configuration can be seen better in this image:(cropped from this document ). The attitude control thrusters are not in plane with the direction control thrusters. This Raytheon patent ...
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  • 1,345
11 votes

High altitude stage separation

Human operators are generally not involved in separation, that's controlled by on-board computers according to the plan programmed into them. 2 way radio lets human controllers see what is going on ...
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  • 18.7k
11 votes
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How did the pilot lockout on Vostok 1 work?

For Vostok, the controls were really not all that impressive by today's standards. The picture below shows the control and information panels on Vostok spacecraft. Here, 1 is the information display (...
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  • 653
10 votes

Is it possible to navigate space travel with no computer?

You can travel in space without any navigation devices or computers at all, establishing suborbital flight and orbital flight is done by the rocket, it's accuracy there that matters and early manned ...
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  • 18.7k
10 votes

Did a flight controller ever answer Flight with a no-go?

The No GO happens all the time. Many recent ULA and Spacex Launches get a NO GO - Most of the time its the Weather and the Range Telemetry guys. High Altitude winds , Range tracking failures , ...
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  • 101
9 votes

How does “space weather” cause reaction wheel failure?

The study was specifically of ITHACO reaction-wheel assemblies that proved to be highly prone to failure in the space environment. These assemblies used steel bearings. Interference with electronics ...
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8 votes

How were the pilots of the space shuttle able to operate the rudder after time in space?

As others have pointed out, shuttle missions never lasted long enough to have serious concerns about the pilot or commander's physical abilities. Also note that the shuttle was a digital fly-by-wire ...
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8 votes
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An program that automatically generates a rocket guidance system?

You really have three separate problems to solve, though it sounds like you're talking about only one of them. The total package is known as GNC, or Guidance, Navigation, and Control. A little more ...
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  • 16.7k
8 votes
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Machine Learning and Classical Navigation, Guidance and Control in Space Exploration

This is an attempt at the first part of your question: "are classical control algorithms better than machine learning approaches". Since I am personally more interested in launch vehicles, the answer ...
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  • 335
7 votes
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Using what technology one can keep a spacecraft truly non rotating

This is the (attitude) lost in space problem. This problem arises, for example, when a spacecraft is first released from the upper stage after launch or when a spacecraft awakens after having been ...
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  • 62.8k
7 votes
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Does the Hubble telescope use a "simple" PID-controller for its pointing control system?

Yes. According to the NASA paper "Hubble Space Telescope Pointing Control System Design Improvement Study Results", in the first full paragraph on page 2, the author states The nominal control ...
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  • 1,095
7 votes

Is it possible to navigate space travel with no computer?

Yes, as long as you don't care where you end up Early spacecraft used electrical controls, but had no computers: Six Vostok each carried one person to orbit. The first flight carried the first man ...
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  • 46.3k
7 votes
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Can the grid fins affect the rotation of the Falcon 9 descent?

Yes, the grid fins can control the rotation of the stage -- and they're the primary mechanism for that during descent, since the cold-gas thrusters have little force and the engines are shut down for ...
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  • 183
6 votes

SpaceX stage 1 reentry control?

I don't have any citation, but the first stage is doing all its own guidance and control; it would be insane to do it any other way. The "acquisition" called out at about 80km altitude is ...
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6 votes

How were the pilots of the space shuttle able to operate the rudder after time in space?

Shuttle missions were normally no more than about two weeks long, unlike many-month ISS missions; Chris Hadfield spent 5 months on-station. The muscular atrophy effects of zero gravity take a while to ...
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6 votes
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How to select/design a control algorithm for spacecraft attitude control?

I'm an aerospace engineer, and took courses in college on spacecraft navigation and control theory. However, I have not programmed a spacecraft attitude controller in my work, and I can't say I've ...
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  • 4,496
6 votes
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Apollo CSM thruster quad orientations vs LM

According to Thomas Kelly's "Moon Lander: How We Developed the Apollo Lunar Module", the primary driver for the positioning of the LM RCS quads was avoiding contamination of the windows with ...
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6 votes

Is aerodynamic lift ever useful in rocket flight?

As far as I know, no. In order to make a cylindrical rocket as light as possible, they are flown to minimize the side loads to the structure -- as close to a zero angle of attack as possible. If they ...
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  • 57.4k
6 votes
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What exactly is rhumb-line control in the context of a launch trajectory?

“Sailing a rhumb line” means holding a constant compass bearing. For short distances, this stays close to a great circle path.But at longer distances and/or higher inclinations, the rhumb-line path “...
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  • 12.3k
6 votes

Why are there advertisements in the Russian ISS flight control room?

They needed the money. Sometimes it seemed the Russian space program would do almost anything to raise money..... (the book goes on to describe renting out the TsUP's lobby to a Czech lighting-...
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5 votes

Is aerodynamic lift ever useful in rocket flight?

You said it yourself, Lift is important for guidance and control. As a matter of fact a rocket is designed in such a way, that the center of pressure is aft of the center of gravity. The distance ...
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5 votes
Accepted

Is aerodynamic lift ever useful in rocket flight?

Angling to get lift is going to increase the atmospheric cross-section of the rocket and so increase drag. For any reasonable angle of attack, the drag force is going to be much larger than the lift ...
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