SpaceX FH: STP-2 : LC-39A : June 25, 2019 - DISCUSSION

[intelati]

SpaceX’s drone ship is heading for a landing zone hundreds of miles off the Florida coast, multiple sources say. No center core landing close to shore, as suggested in an FCC filing earlier this year.

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Edit: remove Twitter embed

[ZachS09]

Why are they taking the drone ship 1,000 km out to sea again? Let me know if any of the following factors are true or false.

They want to try to do the hottest reentry for the center core again and grab the engine base properly.

They want to give more performance for the upper stage to use for the four burns needed to complete the mission. Therefore, they will not position the drone ship 39 km downrange.

They want to do it just because.

[scr00chy]

Maybe they decided to add more ballast to show off the payload capability (or test something)?

[Norm38]

I would guess upper stage performance.  They can use fuel as ballast.  And they can demonstrate extra performance with a longer disposal burn if they don't end up needing the fuel for the mission.
I don't know why they'd put extra performance anywhere except in orbit where it belongs.

[Alexphysics]

Updated FCC filing for STP-2 recovery: 1112-EX-ST-2019

North  27  56  52   West  68  0  55   Autonomous Drone Ship

For those of you that might want to know the distance, that's 1234km from LC-39A (kinda funny the distance is 1234). That'll break the previous record of furthest landing of a Falcon booster by at least 300km.

[gongora]

https://twitter.com/AF_SMC/status/1141099481628364808

The 3700 kg Integrated Payload Stack (IPS) for #STP2 has been completed! Have a look before it blasts off on the first #DoD Falcon Heavy launch! #SMC #SpaceStartsHere

So would the Integrated Payload Stack be the full mass?  It sounds like it should be.

[Elthiryel]

If that's right, it means no ballast and around 800-900 kg for adapters/dispensers according to mass data provided by Gunter's Space Page.

[gongora]

It looks like they ditched one of the ESPA rings and mounted a couple of the COSMIC-2 sats to DSX?  (Either that or the perspective is just confusing me.)

[ZachS09]

Is the FCC license for the original drone ship position still available to download? I don’t see the coordinates in Raul’s SpaceX Map, and I was wanting to input those coordinates in my Google Earth files.

[gongora]

Is the FCC license for the original drone ship position still available to download? I don’t see the coordinates in Raul’s SpaceX Map, and I was wanting to input those coordinates in my Google Earth files.

The original was 0546-EX-ST-2019

[ZachS09]

Is the FCC license for the original drone ship position still available to download? I don’t see the coordinates in Raul’s SpaceX Map, and I was wanting to input those coordinates in my Google Earth files.

The original was 0546-EX-ST-2019

Thanks for that, but before Raul deleted his marker of where the drone ship was gonna be, I saw different coordinates than the ones on the FCC.

Basically, I just calculated the distance from SLC-40 to the coordinates on the FCC, and it was 35 kilometers downrange. For Raul’s coordinates, I remember doing the distance calculation, which was 40 kilometers downrange. Where do those other coordinates come from?

[Alexphysics]

Is the FCC license for the original drone ship position still available to download? I don’t see the coordinates in Raul’s SpaceX Map, and I was wanting to input those coordinates in my Google Earth files.

The original was 0546-EX-ST-2019

Thanks for that, but before Raul deleted his marker of where the drone ship was gonna be, I saw different coordinates than the ones on the FCC.

Basically, I just calculated the distance from SLC-40 to the coordinates on the FCC, and it was 35 kilometers downrange. For Raul’s coordinates, I remember doing the distance calculation, which was 40 kilometers downrange. Where do those other coordinates come from?

Remember the mission is launching from LC-39A not SLC-40, that 5km difference may be due to that.

[jimothytones]

Any weather folks know anything about that cyclone to the north of the LZ?

[Kabloona]

Any weather folks know anything about that cyclone to the north of the LZ?

Apparently no concern through next week.

https://www.accuweather.com/en/hurricane/atlantic

The windy.com model shows the circulation being pushed east gradually, with essentially no pressure drop in the eye, which is forecast to remain over 30 in Hg, and winds around 10 kts in the landing zone in early/midweek, so it looks quite good actually.

[ZachS09]

Is the FCC license for the original drone ship position still available to download? I don’t see the coordinates in Raul’s SpaceX Map, and I was wanting to input those coordinates in my Google Earth files.

The original was 0546-EX-ST-2019

Thanks for that, but before Raul deleted his marker of where the drone ship was gonna be, I saw different coordinates than the ones on the FCC.

Basically, I just calculated the distance from SLC-40 to the coordinates on the FCC, and it was 35 kilometers downrange. For Raul’s coordinates, I remember doing the distance calculation, which was 40 kilometers downrange. Where do those other coordinates come from?

Remember the mission is launching from LC-39A not SLC-40, that 5km difference may be due to that.

Sorry. Wasn't thinking about the actual launch pad.

[Orbiter]

Any weather folks know anything about that cyclone to the north of the LZ?

Not sure what that's about, there's no active tropical storms in the area. That might just be a leftover from TS Andrea a few weeks ago.

[gongora]

https://twitter.com/StephenClark1/status/1141145678627971074

USAF official confirms no ballast, approximate total value of the mission (including spacecraft and launch services) roughly $750 million.

[Skyrocket]

It looks like they ditched one of the ESPA rings and mounted a couple of the COSMIC-2 sats to DSX?  (Either that or the perspective is just confusing me.)

I don't think so. I guess, the perspective from below gives this illusion. The ESPA, which is integral part of the DSX satellite is too small to accommodate the COSMIC-2 satellites.

[emerrill]

https://twitter.com/spaceflightnow/status/1141286545334382592

Is there a fairing attached here? And maybe this will sound stupid, but could it be a "dummy" fairing, with nothing in it? Remember the other day we saw a fairing without markings on it in the HIF?

[FutureSpaceTourist]

Eric Ralph discusses various possible reasons for centre core recovery being so far downrange:

A SpaceX surprise: Falcon Heavy booster landing to smash distance record
By Eric Ralph
Posted on June 19, 2019

In an unexpected last-second change, SpaceX has moved Falcon Heavy Flight 3’s center core landing on drone ship Of Course I Still Love You (OCISLY) from 40 km to more than 1240 km (770 mi) off the coast of Florida.

https://www.teslarati.com/spacex-surprise-falcon-heavy-booster-landing-distance-record/