JF Mezei wrote on Sat, 3 Nov 2018
14:54:23 -0400:

Roscosmos released on-board video of soyuz failure.

https://youtu.be/CrzlMTRVt_I

(booster separation starts roughly 1:23 into video).

Youtube hint: use the "." and "," keys in paused video to
advance/reverse frame by frame).

Also: at roughly 1:26, there appears to be a large portion of video
skipped). And the times in video don't match actual time since launch.


Which confirms exactly what I said happened based on the ground video,
that you claimed wasn't of sufficient resolution to see anything.
Imagine that!


The Roscosmos press release on the issuance of report:
(google translation)
https://translate.google.com/transla...%2F&edit-text=

It does confirm the damaged occiured during final assembly at Baikonour
(so not during manufacturing or transport).


Which you steadfastly argued against. Imagine that!


But contrary to media reports that some claimed "confirmed" what
happened, it wasn't a bent pin that the crews coated with lubricant so
the booster could be slid into place, but rather a very small "push
button" pin designed to detect when separation begins in order to open
an O2 valve to act as reverse thruster at the top of booster to move it
down and out of main rocket.


You need to go read everything that 'some' said again. 'Some' said
that the problem was obviously that the O2 valve on one of the
strap-ons didn't open because they failed to get separation signal.
This is the point where you were arguing about 'pyros'. A list of
possible causes for why this could have happened was given by 'some'
that included 'bad sensor', which is what this was. Now, how do you
supposed that pin got bent. Something to do with them jockeying
around trying to get the strap-on connected due to the larger bent
pin, perhaps? Or do you think that's just all coincidental?

The opening of the O2 valve doesn't act as a 'reverse thruster', by
the way. It acts as a LATERAL thruster to 'push' the top of the
strap-on away from the core stage. 'Some' explained this to you
multiple times, but you're usually so busy arguing with 'some' that
your mind is firmly closed.


It is also not clear whether the assembly workers noticed this or not.
(If not, then the assembly process itself would need to ensure such
sensors are not damaged during mating).


Well, I'm pretty sure there's nothing in the assembly process now that
says "go ahead and damage sensors during mating", so it kind of goes
without saying that you aren't supposed to. There actually IS a
documented tolerance on how much 'bend' is allowable in that sensor
pin, by the way. It's a maximum of six degrees and 45 minutes. Since
there's a tolerance, one assumes it should be checked.


Also, in this failure, the booster, in not distancing its top portion
from core, moved down, with the top of booster ripping through the core
and causing core's propellant to be released.


Pretty much what 'some' said happened and you argued against.


(In the video one can see some long cable-like thing dragging after,
indicating more damage than simple dent in engine bell.


Again, let's go back to how 'some' explained to you that separation
works on this vehicle. As the strap-on loses thrust, it starts to
'lag' the rest of the vehicle. This trips the separation sensor (the
thing that was bent, so that didn't happen). This sends a signal to
both ends of the strap-on. The signal to the top opens the O2 valve.
The signal to the bottom fires the only pyros involved in the
separation which are used to sever some data cables. Since the signal
wasn't sent (bad sensor), the pyros didn't fire and what you see there
is probably the data cable ripped lose from the strap-on because it
was still connected to the core stage.

Seriously, Mayfly, does ANY of this sound AT ALL familiar to you?


QUESTION: at that altitude, would releasing large amounts of kerosene
cause an explosion or would it remain unignited except for propelland
falling behind core's exhaust where there might be some lefover O2
availabls?


Why do you think it would explode? What's the ignition source? So
even disregarding the lack of oxygen, it's unlikely to explode.


Obviously, internally, they know far more than they are releasing to the
media in terms of how/why the sensor was damaged, whether the workers
knew of it or didn't notice etc etc.

So there really isn't enough information available to make judgement on
the problems that allowed this to happen.


Oh, be serious! Damaged during assembly and either no one checked, no
one noticed, or no one reported the possibility, or some combination
of the above. When you have to jack about getting things to mate
correctly, damage is likely. This is precisely the cultural problem
'some' have pointed out repeatedly and that you have steadfastly
argued against, even now.


--
"Some people get lost in thought because it's such unfamiliar
territory."
--G. Behn