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To What Extent do Astronauts Pilot Rockets?


Sanic

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 Since pretty much everyone here plays KSP, we know that we have to fly our rockets manually, all the time. But is it the same in real life? I'm fairly sure the ascent is automated and the rest is done by hand, but I'm not really sure. So this is my question: To what extent are manned rockets controlled by the crew?

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These days, it is highly automated. Backups exist, but for the most part switching to manual is pointless - if the navigation system fails during a launch then a pilot is likely to have no idea what course the rocket is on, and will have no choice but to abort. One of the few things that men can do as well as computers is to dock, so if any of the the docking technologies fail then a pilot can take over, once the craft is close enough to its target. They can also do things such as reboot systems when they fail, which is not automated for fear that "false" reboot situations could occur at critical moments.

(Of course, the astronauts have some very important jobs on board the ISS! Replacing parts is still not something that can be done by robots, not even remote manipulators. But that's not "piloting" nor is it on board a rocket.)

During the Apollo series of missions the astronauts were crucial - the guidance systems had to be recalibrated constantly by the astronauts using star-sight, moon-sight and Earth-sight readings which at that date could not be automated. Some of the readings had to be radioed back to Earth for further calculation (because of the limited computer power onboard) but some could be entered into the navigation system directly. The astronauts also had huge checklists to attend to during the mission, making sure equipment was working as expected: during the first few low Earth orbits before the trans-lunar injection they had to check just about every circuit and system before they could commit to going for the moon. If, during that stage, a fault was detected they would have to decide a) can they fix the problem, B) can they work around it (by, for instance, using circuit breakers instead of faulty switches or using backup equipment), or c) is the mission a bust? This was all done in consultation with ground control, but it was a job the astronauts had to do - none of it could be automated!

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For the boost into orbit, not at all. Computers fly a combination of preprogrammed trajectory and real time calculations. All major maneuvers and burns would be pre-planned and calculated, and even contingencies for use in an emergency. Even unplanned maneuvers would be calculated by computer. I'd say usually, the astronauts punch numbers into a computer which does the work. Softwier is right about the role of astronauts in apollo, but almost all of the actual 'flying' is done by computer. During the lunar landing, the computer controlled the de-orbit burn and attitude using its inertial navigation system and radar to detect altitude. It guided the lem to a preprogrammed area and then the astronauts took partial control, in 'steering' to guide to a suitable landing place. But even during this step the computer controlled the throttle, gimbal, attitude, rcs, everything using the astronauts input to calculate the control needed.

I don't know about docking, i think in apollo it was fairly manual (but i think the computer still had direct control of the rcs and used the astronauts control input and current state of the craft to control attitude and translation.

And of course most things would have a manual override (except probably some things during boost to orbit...) but it would not be the 'normal' operation, in a perfect mission everything would go as it had been planned.

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I can tell you for sure that docking can be done manually, though much is done through automation. However relocating visiting man-rated spacecraft at the ISS, such as the Soyuz most commonly,  is still done largely by hand. The exact timings of these maneuvers IIRC leave a margin for the individual "method" of each pilot.

Edited by Glaran K'erman
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Nobody "flies" rockets. The launch is fully automated.

Most spacecraft are flown with computers. Apollo had the AGC, where the pilots entered "verbs" and "nouns" to issue commands. Soyuz has automated sequences, like MechJeb, that can be enabled/disabled by the crew. There are manual controls for maneuvers and docking, although Russian spacecraft also have automatic docking.

So using MechJeb is actually much more realistic than messing with the WASD keys.

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Wasn't there an article in 2015(?) about a new navigation computer which shortened the approach time to dock at the ISS by several days?

Also there's this: http://www.space.com/11819-nasa-shuttle-space-station-docking-test-storrm-sts134.html

IIRC all ships wanting to dock at the ISS are 'caught' by the Canadarm. I don't know if the arm is computer or manually controlled for this.

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40 minutes ago, *Aqua* said:

Wasn't there an article in 2015(?) about a new navigation computer which shortened the approach time to dock at the ISS by several days?

Nope, it's procedures and more accurate planning that allow same day docking.

One of the reasons it took several days to RV with the ISS is because there's a lot of work to do by the crew. From launch preparation (suiting up, boarding, pre-flight activities...) to the actual docking, simplifying procedures has managed to bring the work load down from several days to a well-packed 15 hour work day. The drawback, obviously, is that this puts a lot of pressure on the crews.

40 minutes ago, *Aqua* said:

Also there's this: http://www.space.com/11819-nasa-shuttle-space-station-docking-test-storrm-sts134.html

IIRC all ships wanting to dock at the ISS are 'caught' by the Canadarm. I don't know if the arm is computer or manually controlled for this.

No, visiting vehicles that are equipped with a CBM (Cygnus, HTV, or Cargo Dragon) need to be berthed by the Canadarm, which is a manual process. Vehicles equipped with a Russian APAS docking system (Shuttle, ATV, Progress, Soyuz) or the new IDS (Crew Dragon or CST-100) can dock autonomously or manually.

 

 

29 minutes ago, Ackoli said:

I think it depends how far away the object is.

No it doesn't.

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9 hours ago, Nibb31 said:

Nope, it's procedures and more accurate planning that allow same day docking.

One of the reasons it took several days to RV with the ISS is because there's a lot of work to do by the crew. From launch preparation (suiting up, boarding, pre-flight activities...) to the actual docking, simplifying procedures has managed to bring the work load down from several days to a well-packed 15 hour work day. The drawback, obviously, is that this puts a lot of pressure on the crews.

No, visiting vehicles that are equipped with a CBM (Cygnus, HTV, or Cargo Dragon) need to be berthed by the Canadarm, which is a manual process. Vehicles equipped with a Russian APAS docking system (Shuttle, ATV, Progress, Soyuz) or the new IDS (Crew Dragon or CST-100) can dock autonomously or manually.

Makes sense the thing who takes time is the orbit matching, compare with KSP that you sometimes uses far longer to approach an orbital target if you mess up the launch. 
If they time the launch and the launch parameters carefully they can end up closer. 
Its also as you say an issue for the astronauts its an long day from launch preparation to dock, it can be better to sleep in the pod and dock the next day as the final approach and docking also takes some hours. 

Do the cargo pods do the final approach automatically or controlled from ISS. Cadarm grab and connect is manual. 

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One thing I haven't found any sources on is what happened when Armstrong "went to manual".

I've "gone to manual" many times in KSP using a mechjeb functions like a descent controller, where I can choose to kill all rotation and horizontal velocity and just control my rate of descent towards the ground.  Moving landing site can be as simple as shoving the stick over and increasing throttle, but then reactivating the descent controller to kill my horizontal velocity I just picked up.  Landing is as simple as killing my horizontal velocity so I am headed straight at my landing site, watching a suicide burn counter til the time reaches zero, activating the descent controller, which kills my horizontal and all but about 3 m/s of my vertical speed, then reducing the vertical speed right before touchdown for a soft landing.

Only thing that goes wrong is KSP is kinda unstable and the control loop between it and the landing assist is wonky.

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For Apollo, during the first part of the flight there were three methods to abort. EDS which was automatic and would eject the capsule and end the flight. The commander could turn the abort handle, the same thing would happen. Lastly an abort could be called from Houston. However, once the escape tower jettisons they were high enough in the atmosphere that an immediate abort wouldn't be needed (and actually might be worse in the end). At this time EDS was turned off (called EDS to manual for your next Apollo 13 viewing)[actually EDS was switched to manual slightly before the tower is jettisoned] and turning the abort handle would implement whatever the best available abort mode is. I believe (not 100% though) that if only the guidance failed, they could manually pilot the rocket to orbit (and possibly the moon) however NASA would probably just choose an abort mode anyway.

 

For the LM, it was intended that the autopilot would land the ship 100%, however the landing area for A11 wasn't an area could land in so they aborted the autoland, moved to a slightly different landing area, and landed manually. From then on all the landings were manual after a certain point because it was proven to be possible (NASA wasn't 100% that a pilot could do it manually which is why manual was the backup),

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12 hours ago, Nibb31 said:

No, visiting vehicles that are equipped with a CBM (Cygnus, HTV, or Cargo Dragon) need to be berthed by the Canadarm, which is a manual process. Vehicles equipped with a Russian APAS docking system (Shuttle, ATV, Progress, Soyuz) or the new IDS (Crew Dragon or CST-100) can dock autonomously or manually.

 

ATV, Progress and Soyuz all use the older SSVP probe/drogue system rather than the newer APAS system (although Soyuz has been test flown with APAS back on Mir).

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Much like what @softweir said, the Apollo missions had a lot of piloting done by astronauts. The ascent was fully automated, but the pilots had some sort of a say in almost everything else. When landing on the Moon, the final program(Program 66 I believe, someone correct me if I'm wrong) would allow the pilot to steer the LEM down to the surface.

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2 hours ago, SomeGuy123 said:

One thing I haven't found any sources on is what happened when Armstrong "went to manual".

I've "gone to manual" many times in KSP using a mechjeb functions like a descent controller, where I can choose to kill all rotation and horizontal velocity and just control my rate of descent towards the ground.  Moving landing site can be as simple as shoving the stick over and increasing throttle, but then reactivating the descent controller to kill my horizontal velocity I just picked up.  Landing is as simple as killing my horizontal velocity so I am headed straight at my landing site, watching a suicide burn counter til the time reaches zero, activating the descent controller, which kills my horizontal and all but about 3 m/s of my vertical speed, then reducing the vertical speed right before touchdown for a soft landing.

Only thing that goes wrong is KSP is kinda unstable and the control loop between it and the landing assist is wonky.

"Manual" on an Apollo LM let Armstrong change the programmed landing point, but the computer was still managing the LM's attitude. Moving the joystick changed the computer's "goal" for horizontal velocity, but it wasn't connected directly to the jets (though it could be set for direct control, as in Apollo 13). Sounds similar to using MechJeb's Translatron.

Fascinating source document here: http://www.princeton.edu/~stengel/LM.pdf

As for the original question, from my research, Americans have controlled rocket engines or RCS manually in-space during Project Mercury, during Gemini 4 (later Gemini flights had on-board computers), and Apollo 13.

 

Edited by Beowolf
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2 hours ago, Frybert said:

For Apollo, during the first part of the flight there were three methods to abort. EDS which was automatic and would eject the capsule and end the flight. The commander could turn the abort handle, the same thing would happen. Lastly an abort could be called from Houston. However, once the escape tower jettisons they were high enough in the atmosphere that an immediate abort wouldn't be needed (and actually might be worse in the end). At this time EDS was turned off (called EDS to manual for your next Apollo 13 viewing)[actually EDS was switched to manual slightly before the tower is jettisoned] and turning the abort handle would implement whatever the best available abort mode is. I believe (not 100% though) that if only the guidance failed, they could manually pilot the rocket to orbit (and possibly the moon) however NASA would probably just choose an abort mode anyway.

 

For the LM, it was intended that the autopilot would land the ship 100%, however the landing area for A11 wasn't an area could land in so they aborted the autoland, moved to a slightly different landing area, and landed manually. From then on all the landings were manual after a certain point because it was proven to be possible (NASA wasn't 100% that a pilot could do it manually which is why manual was the backup),

But wouldn't automatic landings be more reliable?

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48 minutes ago, fredinno said:

But wouldn't automatic landings be more reliable?

Yes and No. This was the reason for the 'automated first' philosophy of the Apollo program. The surface of the moon wasn't really known at the time, and the landing computers couldn't tell if they were landing on a flat surface or in the middle of a boulder field (which was the case with A11). By the point where the pilot took over, most of the landing was done and all that really needed was the final landing spot, which the human eye was better for than the computer.

 

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2 hours ago, Beowolf said:

oint, but the computer was still managing the LM's attitude. Moving the joystick changed the computer's "goal" for horizontal velocity, but it wasn't connected directly to the jets (though it could

THANK you.

As an aside, this means if you wrote a truly realistic spacecraft simulator, you could ditch direct manual control of thruster firing completely.  Unrealistic.  There's a really good reason to ditch it that has to do with synchronization in multiplayer.

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In terms of docking, the most recent manned launch to ISS (Expedition 46) encountered a problem with the docking autopilot system a few moments before docking, and Soyuz commander Yuri Malenchenko switched it to manual and pulled all the way back before doing a manual docking. It was pretty interesting to watch since the stream showed the pilot's screen and you could see the control inputs happening (which I was translating into KSP controls in my head). 

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1 hour ago, peadar1987 said:

I think Neil Armstrong recovered his tumble during the Gemini program pretty much manually though, which is very impressive.

Back in the Gemini days most of the orbital manoeuvering was done manually as few people actually had a good idea of how orbital mechanics translated into manouvres on orbit, so there was a fair bit of trial and error in the early missions

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