SpaceX Falcon 9 / Dragon 2 : SpX-DM2 : May 27, 2020 : DISCUSSION

[Lars-J]

Was it just me or when the CAS got to dragon it kinda ... bumped it? Seemed like Dragon was swinging a bit after arrival. Could have been a visual effect or CAS itself doing it, but was weird

That was more likely the arm swinging slightly as it stopped. The camera is attached to the arm, so it looks fixed when it is not.

[1]

So it seems that mission control is still using quindar tones. Was this present during the shuttle days? Any reason they're still in use now? If there was any previous discussion on this, I missed it.

Edit: Might as well mention that while I'm disappointed in the scrub, I'm pretty happy that they didn't just cut off the broadcast. The detanking, de-crewing procedure is actually pretty interesting to watch; especially now that the webcast has reverted back to purely technical discussion. I'm actually paying more attention to the stream now than I was before the scrub.

[toruonu]

Was it just me or when the CAS got to dragon it kinda ... bumped it? Seemed like Dragon was swinging a bit after arrival. Could have been a visual effect or CAS itself doing it, but was weird

That was more likely the arm swinging slightly as it stopped. The camera is attached to the arm, so it looks fixed when it is not.

Watch it again. I was observing the rubber boundary in comparison to the background objects (landmarks etc) and that was all stationary pointing that it wasn't the CAS that swung.

[Lars-J]

Was it just me or when the CAS got to dragon it kinda ... bumped it? Seemed like Dragon was swinging a bit after arrival. Could have been a visual effect or CAS itself doing it, but was weird

That was more likely the arm swinging slightly as it stopped. The camera is attached to the arm, so it looks fixed when it is not.

Watch it again. I was observing the rubber boundary in comparison to the background objects (landmarks etc) and that was all stationary pointing that it wasn't the CAS that swung.

Do you have a clip? (and anyway the Dragon is far closer, so of course movement relative to Dragon will look more exaggerated than distant objects)

[racevedo88]

Does anyone know if Saturday’s window is also instantaneous.

[whitelancer64]

So it seems that mission control is still using quindar tones. Was this present during the shuttle days? Any reason they're still in use now? If there was any previous discussion on this, I missed it.

Edit: Might as well mention that while I'm disappointed in the scrub, I'm pretty happy that they didn't just cut off the broadcast. The detanking, de-crewing procedure is actually pretty interesting to watch; especially now that the webcast has reverted back to purely technical discussion. I'm actually paying more attention to the stream now than I was before the scrub.

Yes, Quindar tones were used on the UHF frequencies used on the Shuttle.
https://www.hq.nasa.gov/alsj/quindar.html

In the past, Quindar tones were used to trigger equipment to begin and end transmission. Modern systems don’t need that audio prompting, but they still use Quindar tones because it provides cues to the mission control team. When they hear that distinctive beep, it tells them that CapCom has keyed their mic and is about to start talking to the crew. They are trained to halt whatever conversations they are having at the time, to listen to the conversation with the crew, because it may be important.

[whitelancer64]

Does anyone know if Saturday’s window is also instantaneous.

Yes. For SpaceX, launch windows to the ISS are always instantaneous.

[Lars-J]

Does anyone know if Saturday’s window is also instantaneous.

Yes. Instantaneous because of two factors - ISS plane alignment and sub-cooled propellant warning. Every launch to ISS with F9 has an instant window.

[JasonGerend]

Why is at least one of the Crew Dragon windows covered? You see it from the inside as black, and on the outside as having what looks like a bolted/riveted on covering. I did a little web searching and couldn't find an answer, so I knew where to turn!

Just curious - I've had a smile on my face all day from this launch attempt - really exciting progress on the part of SpaceX and NASA!

[Lars-J]

Why is at least one of the Crew Dragon windows covered? You see it from the inside as black, and on the outside as having what looks like a bolted/riveted on covering. I did a little web searching and couldn't find an answer, so I knew where to turn!

Just curious - I've had a smile on my face all day from this launch attempt - really exciting progress on the part of SpaceX and NASA!

Crew dragon originally had 4 windows - two in the front (each side of hatch), and two side windows. The side windows were removed, but they just haven't updated the interior panels for those wall areas (yet), so they appear to be just black from the inside.

[whitelancer64]

Why is at least one of the Crew Dragon windows covered? You see it from the inside as black, and on the outside as having what looks like a bolted/riveted on covering. I did a little web searching and couldn't find an answer, so I knew where to turn!

Just curious - I've had a smile on my face all day from this launch attempt - really exciting progress on the part of SpaceX and NASA!

The black window isn't covered, it's not there. It's a solid plate that fills where the window would have been. NASA requested that the two side windows not be installed. No statement on why, but speculation is to reduce MMOD risk.

[1]

Modern systems don’t need that audio prompting, but they still use Quindar tones because it provides cues to the mission control team. When they hear that distinctive beep, it tells them that CapCom has keyed their mic and is about to start talking to the crew. They are trained to halt whatever conversations they are having at the time, to listen to the conversation with the crew, because it may be important.

Thanks. I understand the need for them back in the 60s, but couldn't think of any technical reason for them to still be in use today. Using it as a 'now hear this!' chime does make sense though; would also explain why they seem to have moved to a softer tone rather than the sharp, single frequency from the Apollo era.

[toruonu]

Was it just me or when the CAS got to dragon it kinda ... bumped it? Seemed like Dragon was swinging a bit after arrival. Could have been a visual effect or CAS itself doing it, but was weird

That was more likely the arm swinging slightly as it stopped. The camera is attached to the arm, so it looks fixed when it is not.

Watch it again. I was observing the rubber boundary in comparison to the background objects (landmarks etc) and that was all stationary pointing that it wasn't the CAS that swung.

Do you have a clip? (and anyway the Dragon is far closer, so of course movement relative to Dragon will look more exaggerated than distant objects)

Made a small clip:

Not quite sure, but feels from looking at it like a bump

[TRS717]

I must say the hatch opening looks to be a bit... fiddly. I'm sure they have a procedure that opens it swiftly in an emergency, but this certainly looks to have taken far more personnel, tools, and time than I would have imagined.

[llanitedave]

I must say the hatch opening looks to be a bit... fiddly. I'm sure they have a procedure that opens it swiftly in an emergency, but this certainly looks to have taken far more personnel, tools, and time than I would have imagined.

I was thinking the same thing, I was surprised at how long it was taking after they had said the pressure had equalized.

[racevedo88]

Does anyone know if Saturday’s window is also instantaneous.

Yes. Instantaneous because of two factors - ISS plane alignment and sub-cooled propellant warning. Every launch to ISS with F9 has an instant window.

thanks

[Yellowstone10]

It looked like Bob and Doug handed back to the closeout crew their velcro-on nametags. That would be a pretty neat space-flown souvenir!

[trekkie604]

Did Doug give #12 closeout dude one of his SpaceX patches?

[Jeff Lerner]

I picked up on this..it looked like Behnken handed ninja #6 back a Spacex name tag he had aboard Dragon...maybe he offered to fly it to space for her ?

[Lars-J]

I must say the hatch opening looks to be a bit... fiddly. I'm sure they have a procedure that opens it swiftly in an emergency, but this certainly looks to have taken far more personnel, tools, and time than I would have imagined.

Sure, and they will get better at it. But it sounded like they had to remove some TPS covering for the mechanism... Being gentle with that would be less of an issue in an actual emergency.