SpaceX Dragon XL

[TrevorMonty]

DoD has very little skin in the Starship game.  Jim is probably right.  But I believe that it should have more.

no.  Not untfil Starship stops morphing and finishes development.

SS will also be launching from Launch Pad 39A which is likely launch location for DoD missions.

[JHošek]

The original plan for HALO was that it would be launched on a commercial launch vehicle which would put it thru TLI. In fact, that was one of three reasons, specifically mentioned by NASA in its "Justification for Other Than Full and Open Competition" document, for selecting NG as HALO contractor in July 2019.

There never was a concrete plan to have HALO delivered to NRHO by SLS.

I will add that the launch vehicle for HALO's predecessor (ESPRIT + Utilization Module) developed as follows:

November 2018 - SLS Block 1B (EM-3)
https://twitter.com/SpcPlcyOnline/status/1060606014779768833


March 2019 - commercial launch vehicle
Source: https://www.nasaspaceflight.com/2019/03/administration-proposes-end-eus-exploration-manifest-rewrite/

[jstrotha0975]

Isn't that wrong since the US habitat module is launching with the PPE?

[DanClemmensen]

Isn't that wrong since the US habitat module is launching with the PPE?

The slide is from 2018. The Gateway plan has changed a lot since then. In the current "plan" as we think we know it, PPE will be pre-mated with HALO prior to launch and PPE+HALO will launch together on a Falcon Heavy. You also need to be careful with your terms. Sure, HALO means "Habitation and Logistics Outpost", but it is really just a fairly small tube with four docking ports. The actual usable "habitat" will be a different module: I-HAB or "International Habitat", which is a slightly larger tube with four docking ports. the Wikipedia article is a bit of a mess due to all fo the evolution in Gateway, so treat it with caution:
     https://en.wikipedia.org/wiki/Lunar_Gateway
You will need to be especially sensitive to the publication dates of the references.

[Zed_Noir]

Isn't that wrong since the US habitat module is launching with the PPE?

The slide is from 2018. The Gateway plan has changed a lot since then. In the current "plan" as we think we know it, PPE will be pre-mated with HALO prior to launch and PPE+HALO will launch together on a Falcon Heavy. You also need to be careful with your terms. Sure, HALO means "Habitation and Logistics Outpost", but it is really just a fairly small tube with four docking ports. The actual usable "habitat" will be a different module: I-HAB or "International Habitat", which is a slightly larger tube with four docking ports. the Wikipedia article is a bit of a mess due to all fo the evolution in Gateway, so treat it with caution:
     https://en.wikipedia.org/wiki/Lunar_Gateway
You will need to be especially sensitive to the publication dates of the references.

AIUI most of the habitable Gateway modules are build using components derived from the pressurized cargo module of the Cygnus logistics vehicle. Which means the Cygnus derived modules could fit in an EELV specified payload fairing with internal diameter of about 180 inches (about 4.6 meters).

The I-Hab module doesn't have a lot of internal habitable volume with 10 m³ as compare to the Crew Dragon's 9.3 m³. Also the backup toilet is in the Dragon XL.

[woods170]

The original plan for HALO was that it would be launched on a commercial launch vehicle which would put it thru TLI. In fact, that was one of three reasons, specifically mentioned by NASA in its "Justification for Other Than Full and Open Competition" document, for selecting NG as HALO contractor in July 2019.

There never was a concrete plan to have HALO delivered to NRHO by SLS.

I will add that the launch vehicle for HALO's predecessor (ESPRIT + Utilization Module) developed as follows:

November 2018 - SLS Block 1B (EM-3)
https://twitter.com/SpcPlcyOnline/status/1060606014779768833


March 2019 - commercial launch vehicle
Source: https://www.nasaspaceflight.com/2019/03/administration-proposes-end-eus-exploration-manifest-rewrite/

First off: I removed the embedded image. Please, do NOT embed images.

Further: emphasis mine.

ESPRIT and Utilization Module never were "the predecessor to HALO".

In the old 2018 reference design, HALO did not exist.

The Utilization Module was an interim solution for logistics/storage and early short-term habitation, including a few work stations. Most of its functions have since been integrated into the design of ESPRIT: the 2018 design for ESPRIT was a pure refueling module. The current ESPRIT design includes the pure refueling module, as well as a pressurized tunnel for logistics/storage, one work-station and it contains 6 windows.

The remainder of the functions of the Utilization Module (early short-term habitation) were moved to HALO during the 2019 redesign. But HALO also supports functions from other 2018 design elements, particularly those of the U.S. Habitat module (again: habitation and work stations) and being host to the airlock module (which in the 2018 design was attached to the U.S. Habitation Module). As such, HALO is much more the descendant of the U.S. Habitation Module than of the Utilization Module.

Thru the 2019 redesign HALO came into existence primarily as a simplified replacement for both the Utilization Module and the U.S. Habitat Module. HALO was intended to be launched on a commercial launcher from day 1. The old 2018 design however, saw most of its elements being launched on SLS.

Another result of the 2019 redesign was that ESPRIT went from being the second module added (after PPE) to being the third module added (after PPE and HALO). This resulted in the Gateway comms package to move from ESPRIT to HALO. But the main function of the 2018 ESPRIT (supporting refueling) remains with the current ESPRIT design. As such, the 2018 ESPRIT is not a predecessor to HALO either.

The above goes to show that during the 2019 redesign a lot of stuff got moved around, or was merged together in a smaller number of less capable modules.

[yg1968]

WORK IN PROGRESS IN FY 2024

Gateway Deep Space Logistics received authority to proceed and awarded procurement of the first Logistics service mission in support of Artemis IV.

See page 78:
https://www.nasa.gov/wp-content/uploads/2024/03/nasa-fy-2025-congressional-justification.pdf

Although not mentioned in the FY25 Budget, it seems very likely that these events occurred back in November 2023, see this prior post:
https://forum.nasaspaceflight.com/index.php?topic=50467.msg2537731#msg2537731

[DanClemmensen]

Can Dragon XL deliver propellants (Xenon and RCS propellant) to Gateway, or will this require a different version or a different "GLS tanker" spacecraft?

I has just assumed if would have this capability, but this is no longer obvious.

Can a GLS tanker deliver PPE propellants directly via the HALP port, or must this wait for ESPRIT-ERM?

All of this takes on more significance as the PPE+HALO payload mass increases. PPE+HALO launches on an FH that does not supply enough Δv to reach NRHO, so PPE consumes propellant to get there.

[Zed_Noir]

Can Dragon XL deliver propellants (Xenon and RCS propellant) to Gateway, or will this require a different version or a different "GLS tanker" spacecraft?
<snip>

Presumably Xenon and hypergolic (RCS) propellant tanks can be placed on the forward external cargo platform and in the non-pressurized section of the Dragon XL.

[DanClemmensen]

Can Dragon XL deliver propellants (Xenon and RCS propellant) to Gateway, or will this require a different version or a different "GLS tanker" spacecraft?
<snip>

Presumably Xenon and hypergolic (RCS) propellant tanks can be placed on the forward external cargo platform and in the non-pressurized section of the Dragon XL.

PPE propellant transfer is supposed to occur via additional transfer connectors in the (extended) IDSS docking interface, so it's plumbing, not just tankage.