Analysis by Ted Molczan suggests that the current JSpOC orbits for objects A and B will reenter during the first half of tomorrow (April 29th UT). http://www.satobs.org/seesat/Apr-2015/0246.html
Quote from: russianhalo117 on 04/28/2015 03:28 pmSpin rate was induced around sep after engine cutoff. Separation system would have started it and Progress deployments accelerated it is a good theory based on the data to date.Thanks for this, and parsing the available data--I concur with your assessment that the spin was induced after s/c sep (despite report of anomalous 3rd stage performance). Could be the sep event, or the thrusters on the Progress service module. Again, both of which I believe are common components across the entire Soyuz family.
Spin rate was induced around sep after engine cutoff. Separation system would have started it and Progress deployments accelerated it is a good theory based on the data to date.
Normally the "A" object is the payload and "B" is the rocket body, but the identities assigned to initial TLEs are not always correct; therefore, I have propagated both orbits to decay, using the above Progress ballistic co-efficient.
Hmm. Wouldn't Progress deployments decelerate the spin? Like in sounding rockets or other spacecraft? I.E. yo-yo despin? Or can it be used to accelerate spin too?
Quote from: satwatcher on 04/28/2015 04:54 pmAnalysis by Ted Molczan suggests that the current JSpOC orbits for objects A and B will reenter during the first half of tomorrow (April 29th UT). http://www.satobs.org/seesat/Apr-2015/0246.htmlJust to flesh that out, quoting a bit more from that link:QuoteNormally the "A" object is the payload and "B" is the rocket body, but the identities assigned to initial TLEs are not always correct; therefore, I have propagated both orbits to decay, using the above Progress ballistic co-efficient.
Exactly same thing can happen with crew capsule. This is a strong warning for Congress and NASA to work diligently toward getting American crew to ISS via US spacecrafts.No effort - money or man - should be spared to get it done ASAP
Exactly same thing can happen with crew capsule.
This is a strong warning for Congress and NASA to work diligently toward getting American crew to ISS via US spacecrafts.
I haven't looked into this, but is it possible for Progress to suffer full gyro lock like Briz-M?? if yes , what consequences and implications exist for the current situation??
Also, this is only the second Progress failure in a programme that started in January 1978.
Quote from: Razvan on 04/28/2015 05:27 pmExactly same thing can happen with crew capsule. This is a strong warning for Congress and NASA to work diligently toward getting American crew to ISS via US spacecrafts.No effort - money or man - should be spared to get it done ASAPLet's be brutal about this. How many people have died on US piloted missions? - 14 (1986 & 2003).How man people have died on Soviet/Russian spacecraft? - 4 (1967 & 1971).This suggests that the Russian route is safer!Also, this is only the second Progress failure in a programme that started in January 1978. Let's see the Americans match that.