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

[lcs]

If there is a cloud deck with no chance of downrange optical tracking or visibility would they still launch?  Aside from PR considerations, lack of optical coverage of a malfunction on a maiden manned flight would seem not prudent.  Will they use airborne tracking assets as backup? 

[Lars-J]

So I know the official forecast is pretty much a lock on no launch, and maybe I'm just an optimist, but I have to think it's not as bad as some are saying.

If you think a 40% chance is “pretty much a lock on no launch”, then someone needs to explain statistical probabilities to you.

I agree with others that booster landing criteria can’t be too far off Dragon landing criteria, because the booster landing spot is a plausible abort landing area.

[quasarquantum]

If there is a cloud deck with no chance of downrange optical tracking or visibility would they still launch?  Aside from PR considerations, lack of optical coverage of a malfunction on a maiden manned flight would seem not prudent.  Will they use airborne tracking assets as backup?

If i remember correctly they had airborne tracking for DM-1 splashdown, i recall infrared images of the capsule coming down under the parachutes. Pretty sure they would do the same for DM-2 for some part of the abort windows... And in general, with modern sensors and all, is there really still a need for optical tracking?

[AndyH]

This could be a major PR event for NASA (& SpaceX) and I feel a last minute scrub may take some of the excitement out of it. NASA is going to need as much public support as possible for the Artemis program and this could be a moment to advertise Bridestine's plans about the future and get people excited about it.

I'm guessing NASA learned that lesson the hard way with a shuttle loss.  The last thing anyone needs to be considering here is excitement or PR or Artemis.

[cebri]

This could be a major PR event for NASA (& SpaceX) and I feel a last minute scrub may take some of the excitement out of it. NASA is going to need as much public support as possible for the Artemis program and this could be a moment to advertise Bridestine's plans about the future and get people excited about it.

I'm guessing NASA learned that lesson the hard way with a shuttle loss.  The last thing anyone needs to be considering here is excitement or PR or Artemis.

Weather is a safety factor as well.

[AndyH]

This could be a major PR event for NASA (& SpaceX) and I feel a last minute scrub may take some of the excitement out of it. NASA is going to need as much public support as possible for the Artemis program and this could be a moment to advertise Bridestine's plans about the future and get people excited about it.

I'm guessing NASA learned that lesson the hard way with a shuttle loss.  The last thing anyone needs to be considering here is excitement or PR or Artemis.

Weather is a safety factor as well.

Of course it is.  No need to blow it out of proportion, though.

[rdale]

If you think a 40% chance is “pretty much a lock on no launch”, then someone needs to explain statistical probabilities to you.

Or I could explain them to you 40% is launch weather only. It doesn’t incorporate any of the 50 sites downrange that are being monitored as well as abort ocean scenarios. So unless those are all 100% GO, then when you incorporate it into the 40% - those are pretty low odds.

[Zed_Noir]

If there is a cloud deck with no chance of downrange optical tracking or visibility would they still launch?  Aside from PR considerations, lack of optical coverage of a malfunction on a maiden manned flight would seem not prudent.  Will they use airborne tracking assets as backup?

If i remember correctly they had airborne tracking for DM-1 splashdown, i recall infrared images of the capsule coming down under the parachutes. Pretty sure they would do the same for DM-2 for some part of the abort windows... And in general, with modern sensors and all, is there really still a need for optical tracking?

A pair of venerable WB-57 nuke sniffers are on standby to support the Demo-2 mission when the Dragon comes back down around September. Looks like aircraft 927 & aircraft 928 are tasked according to the NASA aircraft status web page.
https://airbornescience.nasa.gov/aircraft_status

[Mandella]

I understand they don’t want a last minute scrub - but right now it’s just about 50/50. Florida - in the summer - WELCOMES odds that good

If it was today then sure - scrub yesterday.

That is my thought too. Fifty-fifty is about as good as it gets in Florida in the summer!

[Chris L]

It may be useful to remember that the day NASA waived weather requirements for the ill-fated Challenger mission was also the day that Reagan's State of the Union Address was to be given, no doubt including mention of schoolteacher Christa McAuliffe riding into space that morning.  As an ex-Washington lawyer, I can't help but to think some political pressure was applied to launch.  Hoping no repeat this Wednesday.

[mn]

If you think a 40% chance is “pretty much a lock on no launch”, then someone needs to explain statistical probabilities to you.

Or I could explain them to you 40% is launch weather only. It doesn’t incorporate any of the 50 sites downrange that are being monitored as well as abort ocean scenarios. So unless those are all 100% GO, then when you incorporate it into the 40% - those are pretty low odds.

I don't think all 50 locations need to be green. If I understood correctly, there are 50 locations in groups by abort zone, and in each zone only 1 [some] need to be green. (so much data posted recently I can't find where I saw this).

Edit: Found the source:

https://www.nasaspaceflight.com/2020/05/examining-crew-dragons-launch-abort-modes-and-splashdown-locations/

But Crew Dragon won’t land on a runway; it will splashdown in the Atlantic Ocean if an in-flight abort ever occurs.  And NASA has revealed that 50 predetermined abort landing locations will be monitored for the Demo-2 launch, with each of the 50 locations corresponding to one of the seven in-flight abort modes for Dragon.

A certain, undisclosed percentage of abort landing locations in each abort zone will need to be “go” for landing/recovery weather to commit to launch on Wednesday, 27 May during the single-second 16:33:31 EDT (20:33:31 UTC) launch opportunity.

[rdale]

Oh agreed - they don’t all have to be green. But what I’m saying is you have to add in the non-launch weather parameters. If launch is only 40% go, then when you factor those in the “overall” is going to be even lower.

But as I noted - I may be too much of an optimist but I’m not as low as they are.

[Joffan]

Rogozin in relatively cheerful mood, apparently.

https://twitter.com/SciGuySpace/status/1264989118112595968

Russia's space chief with some nice words for NASA and Crew Dragon: "We will be very pleased when an alternative transport system appears. If the Americans succeed ... we will consider that one of the most important tasks of today's world space program has been solved.

[CorvusCorax]

https://twitter.com/spcplcyonline/status/1265007970951335938

NASA confirms that the backup launch windows for Demo-2 are May 30 at 3:22 and May 31 at 3 p.m.
I've seen June 1 listed in some places, but there is no window that day.

That's May 30 19:22 UTC and May 31 19:00

Passes of ISS over KSC in northeastern direction are

May 30 19:20 UTC -- almost direct overhead pass. Initial phasing angle less than 30 degrees - Dragon could theoretically do one of these ultra-quick same-day direct rendezvous there if they wanted

May 31 18:32 UTC -- pass to the south, leading to initial phasing angle of 135 degrees ish - a bit more than 1/3rd of an orbit. Phasing will take about as long as on the May 27 launch.

[rdale]

Here’s a link to the NHC page looking at the tropical wave.

https://www.nhc.noaa.gov/gtwo.php?basin=atlc&fdays=5

My optimistic attitude has made it down to the 45th WS It was informally modified in today’s press conference to 60% go based on their increased confidence in the reduced precipitation coverage.

[Oersted]

Did this documentary air yet? - Any good?

https://corporate.discovery.com/discovery-newsroom/walton-goggins-to-narrate-discovery-and-science-channels-epic-documentary-nasa-spacex-journey-to-the-future-giving-viewers-a-rare-glimpse-inside-nasa-and-spacex-headquart/

Would love to see it...

[Tomness]

Did this documentary air yet? - Any good?

https://corporate.discovery.com/discovery-newsroom/walton-goggins-to-narrate-discovery-and-science-channels-epic-documentary-nasa-spacex-journey-to-the-future-giving-viewers-a-rare-glimpse-inside-nasa-and-spacex-headquart/

Would love to see it...

I thought it was really good,  nothing we all didn't know. Seeing an outsider watch it and be able answer questions was nice.  Thx NSF! They go for shock and awe with CRS-7,  AMOS-6, Demo-1 Capulsue exploding on  the test stand. They don't talk about those failures being survivable with Crew Dragon's abort systems. CRS-7 capsule could have lived if it had trigger to deploy it's chutes. Doug & Bob just say this why we test.  It was sobering to hear them talk about telling their families and sons that they & the teams have migrated those risks. But there is still risks involved.

[rdale]

No change in the forecast... A warm and humid afternoon but nothing excessive by Florida standards. Isolated showers and storms expected in the area but no widespread rain/clouds.

But it only takes one untimely shower or storm to ruin it

If you're going to the launch, the heat index will get into the lower 90s.

Winds through the atmosphere are remarkably light so no issues there either.

[ChrisC]

SpaceX DM 2 - pre-launch briefing
http://www.space-multimedia.nl.eu.org/index.php?option=com_content&view=article&id=28

Just wanted to say THANK YOU John44 for doing this, and doing it quickly!

[Rondaz]

NASA’s SpaceX Demo-2: Preflight Checkouts, NASA Administrator Briefing and Launch Weather

AuthorAnna Heiney Posted on May 26, 2020

Only one day remains until the planned liftoff of a SpaceX Falcon 9 rocket and Crew Dragon spacecraft carrying two American astronauts, Robert Behnken and Douglas Hurley, on NASA’s SpaceX Demo-2 mission for the agency’s Commercial Crew Program. Liftoff is targeted for Wednesday, May 27, at 4:33 p.m. EDT from historic Launch Complex 39A at NASA’s Kennedy Space Center in Florida. The launch window is instantaneous.

Prior to tomorrow’s targeted launch of the Crew Demo-2 mission, SpaceX will bring the rocket horizontal to perform additional preflight checkouts of Falcon 9, Crew Dragon, and the ground support system, including an inspection of the ground-side chilled water radiator feed that keeps Crew Dragon cool before launch. Today’s checkouts do not impact the flight system or targeted launch date, and the vehicle is scheduled to go vertical later tonight.

Tune in to NASA TV and watch online at 10 a.m. EDT as NASA Administrator Jim Bridenstine, Kennedy Space Center Director Bob Cabana, and astronauts Kjell Lindgren and Nicole Mann discuss the upcoming SpaceX Demo-2 mission to the International Space Station and answer questions from reporters.

The U.S. Air Force 45th Weather Squadron now predicts a 60% chance of favorable weather conditions for NASA’s SpaceX Demo-2 launch. The primary weather concerns for launch are flight through precipitation, anvil and cumulus clouds.

FORECAST DETAILS

Clouds                      Coverage           Bases (feet)             Tops (feet)
Cumulus                    Scattered            3,000                          10,000
Cirrostratus                 Broken             25,000                       28,000

Weather/Visibility:  Rain showers/5 miles
Temperature:  82 degrees

NASA and SpaceX will provide live coverage of the launch activities beginning Wednesday, May 27 at 12:15 p.m. leading up to the lift off of a SpaceX Falcon 9 rocket propelling the SpaceX Crew Dragon carrying NASA astronauts Robert Behnken and Douglas Hurley on their way to the International Space Station.

NASA and SpaceX will provide joint, live coverage from launch through arrival at the space station at 11:39 a.m. on Thursday, May 28.

This will be SpaceX’s final test flight for NASA’s Commercial Crew Program and will provide critical data on the performance of the Falcon 9 rocket, Crew Dragon spacecraft, and ground systems, as well as in-orbit, docking, and landing operations.

https://blogs.nasa.gov/commercialcrew/2020/05/26/nasas-spacex-demo-2-preflight-checkouts-nasa-administrator-briefing-and-launch-weather/