Boeing Starliner
Discussion
Eric Mc said:
Spaceflight is not airline operations. Different risk criteria apply. I would suggest that having people on board the mission that just ended would have ensured a better outcome than total reliance on automation.
Boeings processes are obviously not up to scratch, this particular fault might have been fixed by having people on board, but given their troubles simply saying put people on and it will work is a terrible idea.So far they have issues with getting into (correct) orbit and their landing process, not proven their minimum time in space and their launch abort works fine on paper.
Absolutely nothing to do with their Aircraft certification issues, assume an entirely separate team etc but what exactly have they managed not to screw up yet?
Eric Mc said:
Spaceflight is not airline operations. Different risk criteria apply. I would suggest that having people on board the mission that just ended would have ensured a better outcome than total reliance on automation.
What I was trying to get at was that given everything else going on in the company, Boeing's top execs could see it as too risky for the company to go straight to a manned flight as even the slightest issue affecting crew safety could have repercussions on the company out of all proportion.They are already getting jokes made about them e.g.
"NASA Commercial Crew test flight hatch opening"
Maybe.
It's a pity that commercial and corporate public perception might affect practical and logical decision making for what is after all, an experimental and, at heart, risky by nature, enterprise .
Flying fare paying passengers is a massively different operation to flying professional scientists and test pilots.
It's a pity that commercial and corporate public perception might affect practical and logical decision making for what is after all, an experimental and, at heart, risky by nature, enterprise .
Flying fare paying passengers is a massively different operation to flying professional scientists and test pilots.
As I said earlier, all contracts can be renegotiated. The ironic twist to this mission is that on this mission, having a crew on board would probably have solved the problem before it got to the point where too much fuel had been used up.
It was a bit of an "SCE to AUX" moment, only there was no one on board to flip the switch.
It was a bit of an "SCE to AUX" moment, only there was no one on board to flip the switch.
Einion Yrth said:
"SCE to AUX" was the result of multiple lightning strikes, not flight software of extremely questionable quality.
That's not the issue. It's the fact that the problem could be fixed by the human on board pretty quickly. Although it's not 100% certain, there is the possibility that a crewman or woman might have been able to switch off the over active thrusters whilst they assessed what was going on - thereby stopping the propellant being wasted.For whatever reason, those on the ground could not switch them off before it was too late.
Eric Mc said:
Einion Yrth said:
"SCE to AUX" was the result of multiple lightning strikes, not flight software of extremely questionable quality.
That's not the issue. It's the fact that the problem could be fixed by the human on board pretty quickly. Although it's not 100% certain, there is the possibility that a crewman or woman might have been able to switch off the over active thrusters whilst they assessed what was going on - thereby stopping the propellant being wasted.For whatever reason, those on the ground could not switch them off before it was too late.
That's what they'll be checking in the next few weeks and months.
And, of course, nobody is asking the likes of you or me to fly in it. Test pilots have a very different mentality and logic compared to ordinary folk. The old Alan Shepard quote of "Let's light this candle" sums up their approach to test flying.
And, of course, nobody is asking the likes of you or me to fly in it. Test pilots have a very different mentality and logic compared to ordinary folk. The old Alan Shepard quote of "Let's light this candle" sums up their approach to test flying.
Gemini showed that you can’t reliably eyeball orbital manoeuvres and the current crop of spacecraft are fly by wire anyway.
So assuming a crew could fix the problem presumes that it would not be an Airbus moment where the computer ‘knows better’ and overrides the crews commands regardless. The issue apparently was that the RCS system was trying to hold too precise a heading because the incorrect timer led it to believe it was in a different phase of the mission and it had to apply tighter control logic to the attitude control - remaining within x degrees of heading instead of x+y degrees. That sort of state machine approach where different flight regimes have different limits is akin to the Airbus accident in 1980-something where the air show pilot performed a low pass and then couldn’t throttle up to climb away as the computer thought he was trying to land. Crashed in a forest as I recall.
So assuming a crew could fix the problem presumes that it would not be an Airbus moment where the computer ‘knows better’ and overrides the crews commands regardless. The issue apparently was that the RCS system was trying to hold too precise a heading because the incorrect timer led it to believe it was in a different phase of the mission and it had to apply tighter control logic to the attitude control - remaining within x degrees of heading instead of x+y degrees. That sort of state machine approach where different flight regimes have different limits is akin to the Airbus accident in 1980-something where the air show pilot performed a low pass and then couldn’t throttle up to climb away as the computer thought he was trying to land. Crashed in a forest as I recall.
Gemini is "stone age" compared to modern spacecraft.
It was also over 50 years ago and the Gemini astronauts were making the very first rendezvous in spaceflight history.
They were starting from a knowledge base of pretty much zero. Matters are very different today. Both the Americans and Russians have been rendezvousing routinely since the late 1960s so the knowledge base and experience is vastly better than it was in 1965 and 1966.
And, in actual fact, experienced astronauts today really CAN "eyeball" docking - and have done so on numerous occasions. As an example, on Tim Peake's trip up to the ISS in 2015, the automatic system on the Soyuz malfunctioned and was bringing the Soyuz in on the wrong trajectory. The commander of the Soyuz, Yuri Malenchenko, switched off the automatic system, backed off, and took the Soyuz in manually.
I am pretty sure that a crew on board the Starliner on this recent flight could very well have conducted the rendezvous and docking procedure without too much trouble, barring any other technical issues cropping up. The problem was not with the rendezvous system, it was with the on board timer being incorrectly set. Once the timer was reset, the craft was in good shape. But by the time they were able to reset the timer, they had already expended too much fuel to allow a rendezvous with the ISS to happen. A person on board would very likely have been able to assess the situation very quickly and switch the auto firing system off before too much fuel had been wasted.
One thing that did strike me was how pristine the capsule looked sitting on the desert floor. It showed very little sign of re-entry scorching. This indicates that the heat loads were fairly benign and well within expectations and that heat shield technology has come on a long way, even compared to the Space Shuttle era.
It was also over 50 years ago and the Gemini astronauts were making the very first rendezvous in spaceflight history.
They were starting from a knowledge base of pretty much zero. Matters are very different today. Both the Americans and Russians have been rendezvousing routinely since the late 1960s so the knowledge base and experience is vastly better than it was in 1965 and 1966.
And, in actual fact, experienced astronauts today really CAN "eyeball" docking - and have done so on numerous occasions. As an example, on Tim Peake's trip up to the ISS in 2015, the automatic system on the Soyuz malfunctioned and was bringing the Soyuz in on the wrong trajectory. The commander of the Soyuz, Yuri Malenchenko, switched off the automatic system, backed off, and took the Soyuz in manually.
I am pretty sure that a crew on board the Starliner on this recent flight could very well have conducted the rendezvous and docking procedure without too much trouble, barring any other technical issues cropping up. The problem was not with the rendezvous system, it was with the on board timer being incorrectly set. Once the timer was reset, the craft was in good shape. But by the time they were able to reset the timer, they had already expended too much fuel to allow a rendezvous with the ISS to happen. A person on board would very likely have been able to assess the situation very quickly and switch the auto firing system off before too much fuel had been wasted.
One thing that did strike me was how pristine the capsule looked sitting on the desert floor. It showed very little sign of re-entry scorching. This indicates that the heat loads were fairly benign and well within expectations and that heat shield technology has come on a long way, even compared to the Space Shuttle era.
I wasn’t talking about rendezvous, I was talking about the orbital manoeuvres, where you are basically flying ‘on instruments’ as you can’t look out the window and when you try it’s all counter intuitive. The Gemini pilots learned the hard way that ‘point and squirt’ only worked close up (I.e. the examples you gave). Orbital insertion is more of a maths exercise than a pilotage one.
The other reason for the comparison with Gemini was because those men were top notch test pilots, if anyone could ‘eyeball’ it they could. Today’s astronauts are more scientist than steely eyed missile men. Not to say they don’t have the same courage but they haven’t been flying X-15s by the seat of their pants; everything including their flight training is a lot more planned and controlled than the days of kick the tyres and light the fires.
Hence I feel that you don’t have a ‘stick and throttle’ now, as on the old Gemini or Apollo not do you have the hand flying skills. Everything goes via the computer and you are watching instruments that also don’t have a direct gyro in them but are being calculated by the electronics. They aren’t flying behind a traditional six pack of instruments. So for a more recent example of how a computer can get in the way look at AF447 - the computer in that case knew something was up and ‘asked’ for manual intervention but the pilots couldn’t sort it out partly as they lacked natural flying skills, partly that they didn’t have the ‘right’ instruments (an ab initio pilot on basic instrument flying has it drilled into them that you scan airspeed - something - airspeed - some thing else - airspeed. Etc. ).
What I’m trying to say is that we can’t assume a crew would have had the information to correct the situation - the controllers may have done but lacking comes with the craft they could no more advise a crew than send the correction commands. Strapped in a tin can with no frame of reference (akin to the AF447 pilots) would you be able to spot the erroneous timer, assuming it was even displayed? Or would you sit there wondering why the RCS thrusters were firing (Shades of Gemini 8), paging through instrumentation while your fuel ran down? For all we know the computer would be giving the wrong read outs to the crew about location, attitude etc.
The other reason for the comparison with Gemini was because those men were top notch test pilots, if anyone could ‘eyeball’ it they could. Today’s astronauts are more scientist than steely eyed missile men. Not to say they don’t have the same courage but they haven’t been flying X-15s by the seat of their pants; everything including their flight training is a lot more planned and controlled than the days of kick the tyres and light the fires.
Hence I feel that you don’t have a ‘stick and throttle’ now, as on the old Gemini or Apollo not do you have the hand flying skills. Everything goes via the computer and you are watching instruments that also don’t have a direct gyro in them but are being calculated by the electronics. They aren’t flying behind a traditional six pack of instruments. So for a more recent example of how a computer can get in the way look at AF447 - the computer in that case knew something was up and ‘asked’ for manual intervention but the pilots couldn’t sort it out partly as they lacked natural flying skills, partly that they didn’t have the ‘right’ instruments (an ab initio pilot on basic instrument flying has it drilled into them that you scan airspeed - something - airspeed - some thing else - airspeed. Etc. ).
What I’m trying to say is that we can’t assume a crew would have had the information to correct the situation - the controllers may have done but lacking comes with the craft they could no more advise a crew than send the correction commands. Strapped in a tin can with no frame of reference (akin to the AF447 pilots) would you be able to spot the erroneous timer, assuming it was even displayed? Or would you sit there wondering why the RCS thrusters were firing (Shades of Gemini 8), paging through instrumentation while your fuel ran down? For all we know the computer would be giving the wrong read outs to the crew about location, attitude etc.
Flooble said:
I wasn’t talking about rendezvous, I was talking about the orbital manoeuvres, where you are basically flying ‘on instruments’ as you can’t look out the window and when you try it’s all counter intuitive. The Gemini pilots learned the hard way that ‘point and squirt’ only worked close up (I.e. the examples you gave). Orbital insertion is more of a maths exercise than a pilotage one.
The other reason for the comparison with Gemini was because those men were top notch test pilots, if anyone could ‘eyeball’ it they could. Today’s astronauts are more scientist than steely eyed missile men. Not to say they don’t have the same courage but they haven’t been flying X-15s by the seat of their pants; everything including their flight training is a lot more planned and controlled than the days of kick the tyres and light the fires.
Hence I feel that you don’t have a ‘stick and throttle’ now, as on the old Gemini or Apollo not do you have the hand flying skills. Everything goes via the computer and you are watching instruments that also don’t have a direct gyro in them but are being calculated by the electronics. They aren’t flying behind a traditional six pack of instruments. So for a more recent example of how a computer can get in the way look at AF447 - the computer in that case knew something was up and ‘asked’ for manual intervention but the pilots couldn’t sort it out partly as they lacked natural flying skills, partly that they didn’t have the ‘right’ instruments (an ab initio pilot on basic instrument flying has it drilled into them that you scan airspeed - something - airspeed - some thing else - airspeed. Etc. ).
What I’m trying to say is that we can’t assume a crew would have had the information to correct the situation - the controllers may have done but lacking comes with the craft they could no more advise a crew than send the correction commands. Strapped in a tin can with no frame of reference (akin to the AF447 pilots) would you be able to spot the erroneous timer, assuming it was even displayed? Or would you sit there wondering why the RCS thrusters were firing (Shades of Gemini 8), paging through instrumentation while your fuel ran down? For all we know the computer would be giving the wrong read outs to the crew about location, attitude etc.
It was counter-intuitive to the Gemini guys because nobody had ever done it before and they tended to use aviation techniques which were not appropriate. That is not the case now. Spacecraft crews have a wealth of experince and know full well how orbital mechanics work.The other reason for the comparison with Gemini was because those men were top notch test pilots, if anyone could ‘eyeball’ it they could. Today’s astronauts are more scientist than steely eyed missile men. Not to say they don’t have the same courage but they haven’t been flying X-15s by the seat of their pants; everything including their flight training is a lot more planned and controlled than the days of kick the tyres and light the fires.
Hence I feel that you don’t have a ‘stick and throttle’ now, as on the old Gemini or Apollo not do you have the hand flying skills. Everything goes via the computer and you are watching instruments that also don’t have a direct gyro in them but are being calculated by the electronics. They aren’t flying behind a traditional six pack of instruments. So for a more recent example of how a computer can get in the way look at AF447 - the computer in that case knew something was up and ‘asked’ for manual intervention but the pilots couldn’t sort it out partly as they lacked natural flying skills, partly that they didn’t have the ‘right’ instruments (an ab initio pilot on basic instrument flying has it drilled into them that you scan airspeed - something - airspeed - some thing else - airspeed. Etc. ).
What I’m trying to say is that we can’t assume a crew would have had the information to correct the situation - the controllers may have done but lacking comes with the craft they could no more advise a crew than send the correction commands. Strapped in a tin can with no frame of reference (akin to the AF447 pilots) would you be able to spot the erroneous timer, assuming it was even displayed? Or would you sit there wondering why the RCS thrusters were firing (Shades of Gemini 8), paging through instrumentation while your fuel ran down? For all we know the computer would be giving the wrong read outs to the crew about location, attitude etc.
And I will assume that the crew would know what was happening because the guys on the ground new. They just couldn't act fast enough.
As far as I am aware, there was no issue whatsoever with the rendezvous and docking system on the Starliner. All that was wrong was the mission clock was not set properly. All an on board crew would have needed to do was turn the thruster activity off whilst they assessed what needed to be done. In space, you can stop everything without falling out of the sky (unlike in an aeroplane). The important thing was switching off the rocket motors and stopping the wasting of fuel. Because there was no one on board, the ground team repeatedly tried to send a radio command to the spacecraft to turn the motors off but, for whatever reason, that signal did not get through until too much fuel had been wasted.
And, regarding rendezvous AND docking, as well as the manual options (which Gemini eventually mastered), it takes two to tango - and the ISS can also track and assist an incoming spacecraft until they are close enough for the commander to take over manually.
It wouldn't have been perfect but they might have had a bit more time to correct matters. There seems to be an opinion here that the Starliner has no manual over-ride. Can anybody confirm if this is actually the case?
The odd thing is that once the ground controllers could get their signal re-established, they WERE able to turn things off and set up the spacecraft properly so it did get into an orbit. But by then it was had used up too much fuel. Are you implying that an on-board crew has less control than those on the ground?
The odd thing is that once the ground controllers could get their signal re-established, they WERE able to turn things off and set up the spacecraft properly so it did get into an orbit. But by then it was had used up too much fuel. Are you implying that an on-board crew has less control than those on the ground?
Not so much lacking manual override (although I do wonder exactly how much control the crew can exert) as not having the capacity to gather and diagnose the information in the time available. You know it’s thrusting all over the place (probably) but how do you figure out why? The trajectory is sub orbital so they have to make a burn to get to orbit and if they are aborting they have to make a burn to orientate correctly for re entry. Can you trust your instruments? Mission control have 100s of screens and 10s of people analysing it. The crew have a couple of screens and two people (three of the third crew member can see anything).
There are only 40 switches and two MFDs. It is supposed to have a manual mode but it sounds like there is a heavy reliance on the Computers to show the right screens etc.
There are only 40 switches and two MFDs. It is supposed to have a manual mode but it sounds like there is a heavy reliance on the Computers to show the right screens etc.
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