SpaceX Falcon 9 : PAZ & Microsat 2a/2b : SLC-4E : Feb 22, 2018 : DISCUSSION

[matthewkantar]

If Mr. Steven is going to catch the fairing, I would imagine it would be while she is underway. I wonder how that works? Will the crew navigate to a certain starting point and then engage a SpaceX autopilot? Everything has to be at the same location and velocity at the same time. Who is liable for mishaps?

Matthew

[Lars-J]

Based on the images now in the update thread, I am starting to doubt that this is Fairing 2.0. Or if it is, Fairing 2.0 looks externally almost identical to Fairing 1.0. I just don't see any differences.

[gongora]

Based on the images now in the update thread, I am starting to doubt that this is Fairing 2.0. Or if it is, Fairing 2.0 looks externally almost identical to Fairing 1.0. I just don't see any differences.

It's Fairing 2.0.

[Herb Schaltegger]

Based on the images now in the update thread, I am starting to doubt that this is Fairing 2.0. Or if it is, Fairing 2.0 looks externally almost identical to Fairing 1.0. I just don't see any differences.

There are L2 photos which show some differences. And as you can see, gongora has put the matter to rest definitively.

(Yes, that was an unsolicited plug for L2).

[sevenperforce]

PAZ is vertical on the pad, and I think we have a 5.28-meter fairing. At least if my pixel-counting skills are what they used to be.

It looks no different than the existing one, IMO. And you cannot get 8cm of accuracy from that picture.

My bad. I thought the original fairing was 5 meters even.

No, closer to 5.2m. (see image) Although precision of that is hard to know.

Per ChrisG, it's Fairing 2.0, so....

[acsawdey]

If Mr. Steven is going to catch the fairing, I would imagine it would be while she is underway. I wonder how that works? Will the crew navigate to a certain starting point and then engage a SpaceX autopilot? Everything has to be at the same location and velocity at the same time. Who is liable for mishaps?

Matthew

It does seem like that would be the way to do it. But we haven't seen any permits relating to something transmitting from a fairing half.

If it did transmit its GPS position, altitude, and velocity, it is easy to imagine a system that projects that and figures out a path for Mr. Steven to follow using its dynamic positioning system. Would any permit be required to put an ADS-B transponder on the fairing half? It is an aircraft, from a certain point of view :-)

[Lar]

There is EXCELLENT info in L2 that clarifies exactly how she (Mr. Steven) is likely to catch the fairing.

 In my view Elon also gave a big clue when he called it a catcher's mitt... Ever watch an outfielder catch a fly ball? He/she positions self to expected arrival spot, watches the ball and adjusts position as required.

(the position adjustment by Mr. Steven... that's what you need L2 for)

[marsbase]

Would any permit be required to put an ADS-B transponder on the fairing half? It is an aircraft, from a certain point of view :-)

[Michael Baylor]

There is EXCELLENT info in L2 that clarifies exactly how she (Mr. Steven) is likely to catch the fairing.

 In my view Elon also gave a big clue when he called it a catcher's mitt... Ever watch an outfielder catch a fly ball? He/she positions self to expected arrival spot, watches the ball and adjusts position as required.

(the position adjustment by Mr. Steven... that's what you need L2 for)

Article on this coming soon btw. Nothing definitive so far, but I will be analyzing Mr. Steven's movements during this attempt. Hopefully, there will be a good amount of data points from the satellite tracking.

Yeah, I bought the MarineTraffic upgrade. I will keep everyone posted if anything interesting happens.

[Semmel]

Per most recent weather balloon data from more than 30 mins ago (still waiting on new data), Upper Level Winds were at 101.8% of max allowed. So that's close & why they're proceeding with fueling. If they get below 100%, we'll be OK to launch.

Interesting that this is treated as such a hard boundary. I guess there is no good rule or procedure to say "ok, 100 or 102% of max level winds.. the difference is negligible and probably in the noise of our models, lets fly anyway".

Disclaimer: I do engineering models for a living and its never black and white. There is always a grey zone and you put the hard boundary somewhere in there.

[toruonu]

I was also wondering if the winds fluctuate like this, the weather data is always out of date by at least 20-30 min, does that 100% model the possibility of unfavorable shift in that timeframe?

[JoerTex]

I wonder why this is reported as a balloon, surely they use a radar profiler.  A balloon won't do much more than 1100ft per min.  Radar is now.

[Pete]

I wonder why this is reported as a balloon, surely they use a radar profiler.  A balloon won't do much more than 1100ft per min.  Radar is now.

Radar is also quite useless if all that it can see is clear air. Moving or not, wind or not, if there is nothing *in* the air to reflect the radar, you ain't getting no info on the air movement.

Interesting that this is treated as such a hard boundary. I guess there is no good rule or procedure to say "ok, 100 or 102% of max level winds.. the difference is negligible and probably in the noise of our models, lets fly anyway".

Treating hard limit criteria as something that can be tweaked, leads to someone launching a Shuttle when the outside temperature is 27 degrees colder than the lower allowed limit. And we all know how well *that* decision turned out.

I was also wondering if the winds fluctuate like this, the weather data is always out of date by at least 20-30 min, does that 100% model the possibility of unfavorable shift in that timeframe?

Absolutely.
They are quite aware of the variability of winds, and the limit criteria would include a safety factor that allows for these changes, within certain parameters. One hopes they chose the parameters wisely, but they do tend to err on the side of caution. (usually)

[Lar]

I wonder if Mr. Steven will come in or stay out. I am betting stay out.

[hootowls]

I wonder if Mr. Steven will come in or stay out. I am betting stay out.

BTW, SpaceX is using a different name for this vessel.  Maybe they'll mention it in the post recovery environment.

[cscott]

I wonder if Mr. Steven will come in or stay out. I am betting stay out.

BTW, SpaceX is using a different name for this vessel.  Maybe they'll mention it in the post recovery environment.

Hm.  And it's owned by Guice Offshore now, so it would be "GO Mr. Steven" judging from GO's past naming convention.  Did SpaceX purchase the vessel from GO? Or did GO choose a different suffix than "Mr. Steven"?

[hootowls]

I wonder if Mr. Steven will come in or stay out. I am betting stay out.

BTW, SpaceX is using a different name for this vessel.  Maybe they'll mention it in the post recovery environment.

Hm.  And it's owned by Guice Offshore now, so it would be "GO Mr. Steven" judging from GO's past naming convention.  Did SpaceX purchase the vessel from GO? Or did GO choose a different suffix than "Mr. Steven"?

Different suffix.

[Nehkara]

If SpaceX chose it, then I'd hope it would be "Well I Was In The Neighborhood" or "No More Mr Nice Guy".

[Youronas]

A short analysis concerning the upper level winds. Tomorrow, the conditions directly over Vandenberg should be slightly worse whereas the wind speeds along the flight path are probably a bit slower, hopefully enough for a successful start.

[JWag]

I overlaid the maps of the location of The Recovery Ship Formerly Known As Mr Steven (TRSFKAMS) with the Stage 1 Hazard area (both maps found in the Updates thread). It looks like the fairing (or at least half of it) will fly quite a ways orthogonal to the rocket flight path?

Lots of caveats:
* I did this in MS-paint and obviously had to scale the TRSFKAMS map to fit the hazard map, which introduced distortions
* The maps may be different projections
* Maybe TRSFKAMS mis-reported its longitude? The latitude appears reasonable.