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Real orbital flights of the 60's: pilot or computer??


RealDarko

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Here's my question, what the NASA and the Soviet space agency used during the 60's for their manned flights into stable orbits and moon landings? Were the astronauts responsible to manually pilot the rockets into orbits, turning them into position and controlling the burns, or that was controlled from a computer or from the earth? Really curious to know about it.

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Both.

NASA was tending to give pilots as much freedom to pet their USAF vanity to let the vessel be as manually controllable as possible. So, their manual controls were assisted with then-advanced computers.

***

The Soviet ships were as much automated as possible with as simple electronics as possible, but with the backup manual override,  because who cares what the pilot wants because on the one hand the electronics was more poor and the human assistance was often required, but on the other hand the more poor electronics required more launches which made the human control too expensive and thus impossible.

So, the Soviet crafts were oriented on advanced analog devices (more electrics than electronics) and the possibility of doing as much operations without a human onboard as possible.
They were mostly either autonomous or remotely operated, regardless of the crew presence onboard.
The first digital computers on the crewed ships appeared in mid-1970s, i.e. almost a decade later than on Apollo, but unlike the US ships, the Soviet ones theoretically weren't needing the crew at all, even for redocking.

The same situation was in civil electronics. While in the US a TV-set or a tape recorder was made out of high-quality details, a similar Soviet one was made out of defective details sorted out by the military or industrial facility, having more random characteristics. This made to add various correction schemes (useless in the American TV set), to compensate and balance the signal and to jam the noise. 
This onone hand was making the Soviet TV set more heavy, complicated, and having more probable failure points, but on the other hand gave a good noise resistance and field repairability.

R-7 didn't have a computer at all till late XX.

(Only electrics and mechanics.)

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Although this video is about 1.5 hours long, I really enjoyed it.  It's about the Apollo Guidance Computer, how it worked, and how the crew interacted with it.  It describes what was really happening with all of those 1202 alarms that were going off during the lunar landing descent.

And here's a 15 minute video from Scott Manley where he interacts with some people who have recently gotten an original one of these computers working again.

 

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American crewed spacecraft tended to be flown from the spacecraft itself, either by the crew or by sophisticated onboard computers. The ability to fly the spacecraft by hand was vital to the saving of Apollo 13 after the oxygen tank explosion took out most of its fuel cells and with it the power needed to run the main flight computers. A lot of American astronauts were former military test pilots, which probably had some influence on spacecraft design too.

In contrast, Soviet computer technology wasn't as advanced so the computers were larger and heavier, making them impractical in spacecraft where mass and space are both at a premium; this meant that  Soviet spacecraft were more reliant on ground commands than their American equivalents as they couldn't calculate their manoeuvres in space and needed ground computers to do so. On the other hand, it also allowed the spacecraft to be operated without a crew and this was done many times: the Vostok capsule was operated as an orbital reconnaissance satellite (named Zenit) with cameras inside the capsule instead of a person, while Soyuz needed only minor changes to turn it into a cargo vessel (Progress) which has been used to supply various space stations for over forty years. The Space Shuttle always required pilots to fly it regardless of mission or payload, but the Soviet Buran was designed to be able to fly autonomously and flew to orbit and back successfully with no crew aboard before the whole project ended with the collapse of the Soviet Union.

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3 hours ago, kerbiloid said:

Both.

NASA was tending to give pilots as much freedom to pet their USAF vanity to let the vessel be as manually controllable as possible. So, their manual controls were assisted with then-advanced computers.

***

The Soviet ships were as much automated as possible with as simple electronics as possible, but with the backup manual override,  because who cares what the pilot wants because on the one hand the electronics was more poor and the human assistance was often required, but on the other hand the more poor electronics required more launches which made the human control too expensive and thus impossible.

So, the Soviet crafts were oriented on advanced analog devices (more electrics than electronics) and the possibility of doing as much operations without a human onboard as possible.
They were mostly either autonomous or remotely operated, regardless of the crew presence onboard.
The first digital computers on the crewed ships appeared in mid-1970s, i.e. almost a decade later than on Apollo, but unlike the US ships, the Soviet ones theoretically weren't needing the crew at all, even for redocking.

The same situation was in civil electronics. While in the US a TV-set or a tape recorder was made out of high-quality details, a similar Soviet one was made out of defective details sorted out by the military or industrial facility, having more random characteristics. This made to add various correction schemes (useless in the American TV set), to compensate and balance the signal and to jam the noise. 
This onone hand was making the Soviet TV set more heavy, complicated, and having more probable failure points, but on the other hand gave a good noise resistance and field repairability.

R-7 didn't have a computer at all till late XX.

(Only electrics and mechanics.)

Apollo has digital computers, it was an primitive one but digital. However I'm very sure they used lots of analog controllers to just that most of them was under computer control. 
Even the burns done by Apollo 13 was done using the computer as its more accurate, now they had to find the craft orientation using an sextant and get velocity and distance from the ground and then input the burn duration and heading. Ground then confirm the trajectory is good. 
However Apollo 11 went manual, probably with some stability help like SMARTASS to redirect during landing. 

And analog controllers works well but they tend to be single use, one example Iowa class battleships has lots of them, you have main guns firing at ships and another for ground targets, yes its the same except ground targets don't move. However for ground targets you will often rely on people calling inn your shots and the anti ship computer could not handle that well. 
The secondary guns had separate computers and extra for shooting at aircraft, and you needed multiple of all as it took seconds to reset them so 6 for the main guns. 
Still at the 80's restoration they kept the analog  computers as they worked as well as their most advanced stuff. 

Edited by magnemoe
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1 hour ago, jimmymcgoochie said:

A lot of American astronauts were former military test pilots, which probably had some influence on spacecraft design too.

Probably? Those highly skilled test pilots resented being treated like spam in a can at worst, or trained monkeys at best, and fought for the capability to take control of the craft

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Part of the Apollo mission planning was to land on the edge of the lighted half of the moon.  That way the lander cast long shadows which the pilot could see out the window.  They also had a altimeter radar, but shadows were considered a good way to judge altitude.  The shadows also helped spot boulders or irregular terrain, so the pilot could manually choose a smooth landing site.  

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Smarter Everyday and Linus Tech Tips did a collab video on the Saturn V guidance computer, with a tour by one of the guys who built it. It's an interesting watch.

Original video:

 

Extended behind the scenes video:

 

 

Edited by Beamer
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Thanks for sharing those videos and the info, thing is that I struggle to control my rockets launches in order to reach orbit specially, and I tought, If I cannot properly do it in the game, how those astronauts did manually in real life?

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The reality is most of the ascent through the atmosphere was automated and during the ascent the only real control option the astronauts had was to abort or not abort. It never did go wrong during a manned flight but if it had gone wrong during the first stage, there's little chance the astronauts could have saved the mission by taking manual control. They definitely could take manual attitude and engine control once in orbit though.

KSP is a matter of practice really, both in rocket design and flight. Once you get the hang of it it's easy, so keep at it. It's mostly about developing some consistency during the early take-off, once you get the hang of that you can often ride comfortably to space by locking your SAS prograde (so in essence automated). In KSP, like in RL, if you have to do a lot of manual work to keep stuff from going wrong it's probably a design issue. Wobbly payloads can ruin attitude control, and big fairings can just outright flip your rocket over, especially if what they're hiding is relatively light.

Some pointers if you want them:
 

Spoiler

My ascent profiles tend to be on the steep sides but I generally follow these checkpoints during my ascent to an equatorial orbit:

  1. turn on SAS, max throttle
  2. launch, turn on RCS if the rocket uses it
  3. at 100 m/s or 1 km altitude (whichever comes first) start tilting. How far your ideal tilt is depends on how fast you go off the pad (TWR) but it's typically around 15 degrees off the normal (= 75 degrees pitch), up to 20 degrees or so for higher TWR rockets. Don't tilt too fast, I typically keep my nav ball cross hair on the edge of the prograde marker or just outside it.
  4. once at the desired pitch lock your SAS to prograde and don't touch attitude control anymore. You're now just going to let gravity turn your rocket further in powered ballistic flight. Thanks to the prograde lock you'll always be pointing straight into the 'wind' which reduces your air resistance to the minimum. Shortly after this point you should be reaching maxQ so you might want to throttle down a bit to a 1.5 TWR or so.
  5. With SAS locked to prograde your craft should slowly tilt further by itself as it gains height and speed, keep an eye on it, if it behaves erratically you have a design problem, add struts for wobbly payloads or some tail fins and/or vernors for rockets with big fairings. Throttle back up once past 12 km altitude or so if you throttled down during maxQ
  6. At 15 km you should be at least 45 degrees tilt off the normal, so 45 degrees pitch or lower, work towards that manually if you tilt too slow (and remember that for next time with this craft your initial tilt should be a bit further). If you're tilting too slow you can also simply reduce your throttle a bit rather than taking manual attitude control.
  7. probably around here you need to stage to throw off some boosters, if your craft is pointing prograde there is very little risk of collisions, but separatrons are your friends for heavy SRBs :)
  8. keep an eye on your apoapsis, after this point it's going to run up fast and you want to tilt over more before it hits your target altitude, above 15 km you have most of the atmosphere behind you so start tilting over (slowly) more towards the horizontal, it should be fairly easy to control the rocket now, start pushing your apoapsis away by aiming below the prograde marker but make sure it stays just above the horizon. again tilt slowly, it's easy to overshoot the mark if you rotate too fast which can spell problems. Pro tip, if you want to let the SAS do most of the work, keep it locked to prograde but switch from "Surface" to "Orbit" frame of reference when you want to tilt more, the Orbit prograde marker is typically around 10 degrees below the Surface one at this point.

From there you pretty much just stop boosting when your apoapsis is at the desired height (I usually aim for 80 km) and circularize. Above 50km it's safe to discard your fairings, no need to drag those along to orbit. Exact numbers in the above are somewhat variable depending on how you design your rockets, how quick you are with the controls, etc, but it's a good starting point. At every flight, notice what could be better and adjust your checkpoints for that. After a while, you'll by putting heavy loads in orbit like a pro while hardly having to touch your attitude controls.

MechJeb or Kerbal Engineer can give you precise readouts for things like TWR, dynamic pressure, ap/pe, pitch heading and roll, etc.

 

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I have a lot of problems during ascent, turning the rocket at the precise moment and keeping there the needed time, etc. That's why I tought, how they did it back then? Seems I would need that small piece of equipment installed on my rockets for the orbital phase. :(

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If you over-build your rockets and don't mind being sub-optimal, you can launch straight up until about 35km where aero stops being an issue, and then turn to 45 degrees up/east until your ap is above 70km or close to your desired orbit, then turn straight east until your pe is the desired height.(low TWR rockets may need to keep the angle above the horizon for longer, high TWR rockets can use a planned maneuver node at ap and may coast for several seconds before starting that burn)

Edited by Terwin
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The cheapest transit to Mars/Duna is achieved by waiting till sunrise (which aligns  up with the direction of Kerbin's motion around the sun)  Then just hold straight up to surface (don't use the radial out heading because it flips when you go from surface orientation to orbit orientation).

In real life this would be a good way to get to Mars.  The side boosters are easier to land at the initial launch pad, so they can be bigger relative to falcon heavy.  You could even do some version of asparagus staging and land the boosters at the initial site.

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23 hours ago, jimmymcgoochie said:

The Space Shuttle always required pilots to fly it regardless of mission or payload, but the Soviet Buran was designed to be able to fly autonomously and flew to orbit and back successfully with no crew aboard before the whole project ended with the collapse of the Soviet Union.

The real reason the Shuttle required astronauts was political.  NASA wanted to launch 7 astronauts as many times as they could, and using crewed flights to launch satellites was a way to get Congress to fund more and more crewed missions.  As far as I know (and this might only be with the latest revision of electronics), the only thing really required for an uncrewed shuttle launch/landing was an extra long cable (and presumably quite a bit of software, I doubt NASA was willing to let anyone write it without an act of Congress).  This made every satellite/probe proposal have to think whether or not such a mission was worth risking 7 lives just to get it in space.

Don't forget that the computers NASA had on the ground were unlikely to be all that spectacular.  The birth of supercomputing can be traced to CDC shipping the CDC6600 in 1964, but early models typically went to intelligence services (who paid a hefty premium for serial #0001 or whatever special model CDC was selling).  They may have been able to check the Apollo trajectories on one of these, but recent history implies that they'd prefer hand/sliderule calculations (it didn't help that Seymour Cray didn't like parity memory either).  64 bit floating point calculations were an afterthought in computing before the CDC6600, and tend to be rather important in computing for spaceflight (KSP uses 32 bit floats, and this leads to all sorts of issues most notably the "Kraken" of yore that simply deleted ships going too fast or too far from Kerbin.  Havester was so impressed by his work-around to prevent this that he named his next company after the trick).

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MechJeb has it all. The Ascent Guidance module should have everything you need. I never use this module so don't ask me how to work it, but from what I understand it has an autopilot that will fly your rocket to orbit based on a selected flight path and it can even give you a countdown to launch a direct intercept to a vessel in orbit.

If you just want to "Fly by the numbers" rather than using WASD and eyeing the nav ball, you can use the Smart A.S.S. module. Set Mode to "SURF", click "SURF" below that. For an equatorial orbit (and assuming default VAB rotation for your control module), enable Heading, Pitch and Roll control and set them all to 90, launch and hit the Execute button. Then just use the little - (minus) button next to "PIT" to decrease your pitch in 1 degree steps. This can give you more precise control than a keyboard.

9tKN8JLn_o.png

Finally there's the Maneuver planner module for setting up (and automatically executing if you want) circulization burns, plane changes, transfer burns etc.

It has a lot more tools, I've been using it for years but I still frequently find new stuff.

 

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On 10/20/2022 at 2:42 AM, Beamer said:

MechJeb has it all. The Ascent Guidance module should have everything you need. I never use this module so don't ask me how to work it, but from what I understand it has an autopilot that will fly your rocket to orbit based on a selected flight path and it can even give you a countdown to launch a direct intercept to a vessel in orbit.

If you just want to "Fly by the numbers" rather than using WASD and eyeing the nav ball, you can use the Smart A.S.S. module. Set Mode to "SURF", click "SURF" below that. For an equatorial orbit (and assuming default VAB rotation for your control module), enable Heading, Pitch and Roll control and set them all to 90, launch and hit the Execute button. Then just use the little - (minus) button next to "PIT" to decrease your pitch in 1 degree steps. This can give you more precise control than a keyboard.

9tKN8JLn_o.png

Finally there's the Maneuver planner module for setting up (and automatically executing if you want) circulization burns, plane changes, transfer burns etc.

It has a lot more tools, I've been using it for years but I still frequently find new stuff.

 

Thanks a lot! Will need to check that, I feel is just what I need.

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