Comments by "Vikki McDonough" (@vikkimcdonough6153) on "Scott Manley"
channel.
-
312
-
183
-
171
-
168
-
130
-
106
-
100
-
87
-
71
-
68
-
61
-
46
-
38
-
38
-
38
-
33
-
30
-
24
-
24
-
22
-
22
-
19
-
17
-
16
-
14
-
14
-
14
-
13
-
13
-
12
-
12
-
11
-
11
-
11
-
11
-
11
-
11
-
10
-
10
-
10
-
10
-
10
-
10
-
9
-
9
-
9
-
9
-
9
-
8
-
8
-
8
-
8
-
8
-
8
-
8
-
7
-
7
-
7
-
7
-
7
-
7
-
7
-
7
-
7
-
6
-
6
-
6
-
6
-
6
-
6
-
6
-
6
-
6
-
6
-
6
-
6
-
5
-
5
-
5
-
5
-
5
-
5
-
5
-
5
-
5
-
5
-
5
-
5
-
5
-
5
-
5
-
5
-
5
-
5
-
5
-
5
-
5
-
5
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
4
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
3
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
2
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
Still, having boosters that can't be shut down or throttled back means that, if there's a problem with one of the boosters, it essentially guarantees an abort. Whereas, if one is using boosters that can be controlled in real time, then one can try to compensate by throttling the booster(s) back somewhat, or, if need be, shutting them down and performing an early booster jettison. Trying to jettison an SRB or SRBs while it's still firing at full thrust is rather hard to do without destroying the entire stack.
This is all the more egregious when you consider that extinguishable solid-fuelled rockets have been around since the 1960s, the first having been the U.S. [LGM-30 Minuteman](https://en.wikipedia.org/wiki/LGM-30_Minuteman) ICBM, and that making a solid rocket extinguishable in flight [is remarkably simple](https://en.wikipedia.org/wiki/LGM-30_Minuteman#Edward_Hall_and_solid_fuels).
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
@spetsnatzlegion3366 Any SSME failure between liftoff and two-engine-TAL capability (usually around T+150) would have necessitated an RTLS abort (even an SSME failure right at liftoff still wouldn't have caused the vehicle to "crash straight into the ground", due to the massive amounts of thrust from the SRBs, which would leave the vehicle in a good-for-an-RTLS energy state following SRB separation), as would certain failures in non-engine systems (generally failures that would either require getting the orbiter back on the ground intact in the absolute fastest way possible [such as a cabin leak, which would result in loss of cooling for critical equipment; or a loss of quantity/pressure in both fuel-cell freon loops, which would eventually result in a loss of fuel-cell cooling, failure of all three fuel cells due to overheating, and a loss of all electrical power], or jeapordise its ability to survive an aerodynamically-braked reentry [such as a failure of two of the orbiter's main electrical busses, which would prevent the ET umbilical doors from closing; this would require an RTLS, if possible, due to the benign thermal environment resulting from the use of engine thrust rather than aerodynamic drag to shed speed]) at any point prior to negative return (the point after which the vehicle would be too far downrange and too high-energy to return to the launch site; usually around T+230).
In the context of the ascent phase of a space-shuttle mission, that is not a "very thin window of time".
1
-
1
-
1
-
12:46 - It probably could've been done, from a purely engineering standpoint (a number of bombers with multiple crew decks do manage to have ejection seats for all the crew, by building hatches and tunnels into the cockpit structure for the crew to eject through), but doing all that to the shuttle without prohibitive mass penalties (both from the seats and ancillary paraphernalia themselves, from the extra equipment and interlocks needed to keep the seats from going off while on the ground, in orbit, or during reentry, from needing more space elsewhere to place the systems and equipment that would've had to be moved out of the way, from the extra piping and cabling and whatnot necessary to keep that relocated equipment operational, from the extra structural-element beefing-up required to be able to reroute primary structural elements around the hatches and tunnels without weakening the orbiter's structure overall) would've been a massive headache, at best.
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1