Here is some info (in Russian) from a guy who apparently worked at the mission control.
11. Another attempt to stop the rotation using "another collector" [a backup set of thrusters?] was unsuccessful.
I just haven't been able to get any speculation that covers the whole set of data that we have.
Here is some info (in Russian) from a guy who apparently worked at the mission control. Here is my translation:Plain facts about the Progress M-27M spacecraft1. Telemetry both from the launch vehicle and from the Progress spacecraft stopped 3 seconds before the spacecraft separation.2. According to ground observations, Progress did separate from the the launch vehicle.3. According to the sporadic telemetry received, two antennas didn't deploy and the onboard computer crashed. A decision to switch from the 4-orbit approach and docking maneuver to the traditional 2-day scheme was made.4. According to "radio monitoring" of the orbit, the apogee was 40km higher than planned.5. Launch vehicle experts from the Samara plant [which produces Soyuz rockets] reported to the investigative body that the orbital insertion was nominal and that the radio equipment used to determine the orbit parameters was faulty.6. After the 2nd orbit, these launch vehicle experts admitted that they couldn't confirm the spacecraft separation due to the lack of telemetry, and the orbital data they reported earlier were based on the planned insertion orbit and not on actual spacecraft data.7. After switching on the TV transmitter, it was determined that the Progress rotates at about 1 revolution per 3 seconds. This explains the sporadic telemetry reception.8. NORAD detected a cloud of 44 fragments between the 3rd stage and the spacecraft.9. The next day, an attempt was made to stop the spacecraft rotation. It wasn't successful - despite the fact that spacecraft thrusters did work. Experts came to the conclusion that fuel lines were damaged. [working thrusters with damaged fuel lines looks like a contradiction to me, but this is what the text says]10. Switching the spacecraft to manual control was deemed pointless.11. Another attempt to stop the rotation using "another collector" [a backup set of thrusters?] was unsuccessful.12. The spacecraft is officially considered uncontrollable. The orbit is being monitored.13. An uncontrolled reentry is expected between May 5 and 8.14. That's the whole facts for now.
Most likely 3rd stage exploded, "kicked ass" of the progress, punctured various systems with fragments.We are tired to lose the spacecraft because someone did not do their job. It it the second time when 3d stage destroys the spacecraft."Every error has a family name", I'd start giving prison terms already.
Here is some info (in Russian) from a guy who apparently worked at the mission control. Here is my translation:...14. That's the whole facts for now.
Quote from: edkyle99 on 05/01/2015 04:32 pmCould RD-0110 have run to propellant starvation and suffered a bad shutdown as a result?This is the nightmare scenario for any bi-prop system, where one prop stops feeding [several causes] while the other continues. It's why you have low-level sensors for the SSMEs. Ox-rich burn can be 'energetic' very rapidly.
Could RD-0110 have run to propellant starvation and suffered a bad shutdown as a result?
Quote from: gonucelar on 05/02/2015 03:32 amHere is some info (in Russian) from a guy who apparently worked at the mission control. Here is my translation:Plain facts about the Progress M-27M spacecraft1. Telemetry both from the launch vehicle and from the Progress spacecraft stopped 3 seconds before the spacecraft separation.2. According to ground observations, Progress did separate from the the launch vehicle.3. According to the sporadic telemetry received, two antennas didn't deploy and the onboard computer crashed. A decision to switch from the 4-orbit approach and docking maneuver to the traditional 2-day scheme was made.4. According to "radio monitoring" of the orbit, the apogee was 40km higher than planned.5. Launch vehicle experts from the Samara plant [which produces Soyuz rockets] reported to the investigative body that the orbital insertion was nominal and that the radio equipment used to determine the orbit parameters was faulty.6. After the 2nd orbit, these launch vehicle experts admitted that they couldn't confirm the spacecraft separation due to the lack of telemetry, and the orbital data they reported earlier were based on the planned insertion orbit and not on actual spacecraft data.7. After switching on the TV transmitter, it was determined that the Progress rotates at about 1 revolution per 3 seconds. This explains the sporadic telemetry reception.8. NORAD detected a cloud of 44 fragments between the 3rd stage and the spacecraft.9. The next day, an attempt was made to stop the spacecraft rotation. It wasn't successful - despite the fact that spacecraft thrusters did work. Experts came to the conclusion that fuel lines were damaged. [working thrusters with damaged fuel lines looks like a contradiction to me, but this is what the text says]10. Switching the spacecraft to manual control was deemed pointless.11. Another attempt to stop the rotation using "another collector" [a backup set of thrusters?] was unsuccessful.12. The spacecraft is officially considered uncontrollable. The orbit is being monitored.13. An uncontrolled reentry is expected between May 5 and 8.14. That's the whole facts for now.This guy leads TORU operation group in Baikonur, exams cosmonauts on manual spacecraft control . He refers to the spacecraft as "we, ours" and launcher guys as "they".And if you read his further comments:QuoteMost likely 3rd stage exploded, "kicked ass" of the progress, punctured various systems with fragments.We are tired to lose the spacecraft because someone did not do their job. It it the second time when 3d stage destroys the spacecraft."Every error has a family name", I'd start giving prison terms already.Yeah he feels that sorry.
Can someone remind me what happened the first time the "3rd stage destroyed the spacecraft"?
Progress M-12M in August 2011 - didn't even reach orbit because the 3rd stage engine failed.
Quote from: gonucelar on 05/02/2015 03:32 am11. Another attempt to stop the rotation using "another collector" [a backup set of thrusters?] was unsuccessful.I guess this is the redundant second manifold he is talking about.Quote from: baldusi on 05/02/2015 12:19 amI just haven't been able to get any speculation that covers the whole set of data that we have.How about this scenario:- Malfunction in RD-0110 leads to higher power output than planned- 3 seconds before staging overpowered RD-0110 leads to RUD- RUD cuts of telemetry- RUD leads to venting and/or explosion, which leads to a rotation of 3rd stage and Progress (there must have been some force for quite a while to create that angular momentum)- staging occurs, 3rd stage hits Progress. Or staging can't fire all bolts and staging tears apart parts of Progress- while staging/collision: demolition of Progress propulsion section, pressure vessels, ...
Gas Generator's RUD is not that bad, and they would have had the whole Block-I tanks between the RD-0110 and the Progress. I could rather see something on the Soyzu-2.1a control system. If they had over run the engines a bit, the vibration could have generated a pipe dislocation. I rather see that the transient to engine shutdown was longer and might have generated a re contact. But is not quite a good fit, either.
And now for something completely different:The next issue is going to be whether the Soyuz booster is safe for a crewed launch.My first answer is: sure, because Soyuz is designed so that if the PAO propulsion system fails at separation, the Soyuz descent module will re-enter very quickly.However, a new failure mode seems to have emerged, where the third stage overperforms and then kills the PAO. In that case, as we are seeing, the spacecraft does not decay in two or three days, but rather 10 days, and the Soyuz life support system cannot maintain a 3 person crew for that long.My recommendation would be to delay the next Soyuz crew launch, until another unmanned Soyuz launch is conducted, even if it means a 3 person crew at ISS for a month or two.
My recommendation would be to delay the next Soyuz crew launch, until another unmanned Soyuz launch is conducted, even if it means a 3 person crew at ISS for a month or two.
Quote from: Danderman on 05/02/2015 08:29 pmAnd now for something completely different:The next issue is going to be whether the Soyuz booster is safe for a crewed launch.My first answer is: sure, because Soyuz is designed so that if the PAO propulsion system fails at separation, the Soyuz descent module will re-enter very quickly.However, a new failure mode seems to have emerged, where the third stage overperforms and then kills the PAO. In that case, as we are seeing, the spacecraft does not decay in two or three days, but rather 10 days, and the Soyuz life support system cannot maintain a 3 person crew for that long.My recommendation would be to delay the next Soyuz crew launch, until another unmanned Soyuz launch is conducted, even if it means a 3 person crew at ISS for a month or two.From what I understand the next crew is launching on a Soyuz FG, a different variant of the Soyuz rocket family. That said both Soyuz 2 and Soyuz FG share an RD-0110 engine in the upper stage so if the fault does lie with the engine manned launches may have to be suspended.
Quote from: Danderman on 05/02/2015 08:29 pmMy recommendation would be to delay the next Soyuz crew launch, until another unmanned Soyuz launch is conducted, even if it means a 3 person crew at ISS for a month or two.There is a Soyuz 2-1A launch with a Kobalt M satellite on May 15, two days after the investigate commission is due to issue their preliminary report. I think it's safe to say that one will be delayed.
I'd like to ask some questions about orbit decay and re-entry position prediction - on the example of Progress M-27M:Currently, Progress' orbit has perihelion at ~ 47° North -- is it fair to say that re-entry occurs most likely at perihelion ?During orbital decay, could perihelion drift significantly?