Human-Class Delivery Lander (HDL)¶
Summary. A large uncrewed cargo lander for the lunar South Pole region in the Foundational Exploration segment. It can land cargo that stays on the lander (such as a surface habitat) or offload it to the surface. Its examples of large cargo are the Pressurized Rover, surface habitats and "future surface power elements" (ADD Rev C, p. 56). It is a Transportation Systems element, added in Rev A, and its header image shows the same two commercial systems as the Human Landing System's.
All page numbers are ADD Rev C unless noted.
NASA's description¶
"The Human-class Delivery Lander (HDL) supports delivery missions to the lunar South Pole region during the Foundational Exploration segment. HDL can deliver a wide range of small to large lunar surface assets as cargo, including cargo that remains integrated with the lander on the lunar surface. HDL also offers offloading capabilities, delivering cargo directly to the lunar surface.
Examples of large cargo include the Pressurized Rover, surface habitation elements, and future surface power elements. HDL can also deliver smaller cargo items, either co-manifested with larger items or as many small items grouped together.
HDL is not intended to deliver crew. Crew interaction with the large cargo lander occurs primarily through EVA access to cargo. For cargo that remains integrated with the lander — such as a surface habitat — this includes EVA ingress/egress capability.
During transit from Earth and while on the lunar surface, HDL supports cargo with needed services until the it is ready to operate independently. Once the lander completes operations and enables cargo to operate independently, it transitions to a safe condition/state." (p. 56, "until the it" as printed)
At a glance¶
From the element one-pager (p. 56).
| ADD section | 2.3.6 (p. 56) |
| Implementing program | Human Landing System Program; printed beneath: Moon to Mars Program Office |
| Functional mappings | Appendix B, B.3.6 |
| Segments | Foundational Exploration only |
| Sub-architecture | Transportation Systems |
| Added in | Rev A (elements index) |
| Header image | "Renderings of the two commercial systems for the Human-Class Delivery Lander: the SpaceX Starship and Blue Origin Blue Moon lander. (Credit: SpaceX/Blue Origin)" |
Compared with the other cargo carriers¶
The ADD sizes its three lunar delivery elements against each other:
- CLPS "can provide lunar delivery capabilities in addition to those offered by other elements, like the Human-class Delivery Lander" (p. 47).
- The Lunar Surface Cargo Lander "delivers assets to the Moon, much like the HDL or CLPS elements. However, the anticipated capability of the element is much smaller than HDL, delivering moderate amounts of cargo to the lunar surface" (p. 59).
The HDL's named large cargo are themselves elements: the Pressurized Rover and, by type, the Initial Surface Habitat and power elements such as the Lunar Nuclear Fission System. The ADD names the categories, not those specific elements (p. 56).
In the ACR24 white papers (2024)¶
The 2024 paper "Lunar Surface Cargo", older than Rev C, gives the HDL a capacity that Rev C's one-pager doesn't. Page numbers in this section are the paper's.
- Capacity. Its Table 1 lists "HDL Cargo Lander" at "0 – 12,000 or 15,000" kg, provider U.S. (p. 3). The HDL is the cargo variant in the HLS program, which "includes crewed landers and cargo lander variants called Human-class Delivery Landers (HDL)" (p. 2).
- The only large lander. "HDL is the only lander currently expressed in the architecture that can deliver beyond 500 kg to the lunar surface" (p. 6). Figure 2 marks "HDL Lander Capability" across the top of its chart, above a "Demand Gap Opportunity" that the text puts at 500 to 12,000 kg (p. 3).
Revision B added the Lunar Surface Cargo Lander, sized between CLPS and the HDL. Whether the 2024 capacity still holds is not stated in the sources read. The context is on Transportation Systems.
In the executive overviews (2023 and 2024)¶
Both are older than Rev C; page numbers are their PDF pages.
- Added in 2023, to Human Lunar Return. "This lander will transport cargo for human lunar missions. Crew members will arrive aboard the Human Landing System, and additional cargo will arrive aboard the Human-class Delivery Lander" (2023 overview, PDF p. 10). The overview adds it to Human Lunar Return; Rev C maps it to Foundational Exploration only (p. 31; open question 33).
- Two providers in 2024. The elements spread labels the HDL's two systems "SpaceX Starship" and "Blue Origin Mark 2 Cargo", under "Lunar Freight Deliveries" (2024 overview, PDF p. 24). Rev C's header image is captioned "SpaceX Starship and Blue Origin Blue Moon lander" (p. 56). The overview's HLS tile has "Blue Origin Blue Moon". The wiki doesn't say whether "Mark 2 Cargo" names a version of Blue Moon.
Functions (ADD Appendix B.3)¶
B.3.6.1 maps five functions, all in Foundational Exploration (p. 156). Titles are the ADD's. None is on the Users Guide's list of Phase 1 functional gaps (Users Guide, pp. 8–10; Phase 1 functional gaps; the wiki's check).
| ID | Function |
|---|---|
| FN-T-206 L | Transport large asset(s) from Earth to the lunar surface |
| FN-T-402 L | Provide precision landing for cargo transport to the lunar surface |
| FN-T-403 L | Enable landing on the lunar surface under all lighting conditions |
| FN-P-305 L | Provide bi-directional power exchange capability |
| FN-M-403 L | Unload large assets on the lunar surface |
The HDL is the only element mapped to FN-T-206 L and FN-M-403 L. B.3 gives no capacity: its cargo functions say "large asset(s)", not a mass. The sheet's "Human-Class Delivery System" column has the same five (Lunar function allocation).
Unloading by size, in the ADD.
- Limited cargo, 100s of kg (FN-M-401 L): mapped to CLPS and the HLS.
- Large assets (FN-M-403 L): mapped to the HDL.
- A moderate amount, 1000s of kg (FN-M-402 L): in no ADD table for Foundational Exploration. The lunar spreadsheet marks it Unallocated (Lunar function allocation).
Gaps that mention it¶
None by name (search of both spreadsheets). Offloading cargo is the subject of #0806 Payload Offloading, Handling, and Manipulation; the gap doesn't name the HDL.
Changes since Rev C¶
- "HDL Programs" for heavy cargo after Artemis V. NASA's Building the Moon Base fact sheet of 24 March 2026 lists, among commercial roles: "Increasing the demand for crew and heavy-cargo beyond Artemis V, with redundant pathways to the Moon and leveraging Human Landing System and HDL Programs" (Building the Moon Base fact sheet, p. 2). It doesn't expand "HDL". Reading it as this element is the wiki's match, by acronym. Note that Rev C has the Human Landing System Program implementing the HDL, while the fact sheet lists "Human Landing System and HDL Programs" as two. The same fact sheet has Phase 2 cargo on "low, medium and heavy cargo-class landers" and Phase 3 on "low cost, reusable heavy lift capabilities", naming no lander in either phase.
- "Human-class Delivery Landers", briefed at Ignition, March 2026. The Moon Base Program's deck has a slide headed "Large Cargo Landers": "Drawing on the Human Landing System for cargo with Human-class Delivery Landers", over two renders of crew landers carrying cargo. Its overview of capabilities attaches "HDL" and "CLPS" to "TRANSPORTATION: LANDERS" (Ignition deck 2, slides 42 and 47). The name is this element's, as Rev C prints it, and "Drawing on the Human Landing System" fits Rev C's HLS Program implementing it; the match is still the wiki's, since the deck doesn't cite the ADD. The deck gives no capacity and no phase for the landers. Its per-year tables show large landers (three stacked blocks) from 2031 and in every year of Phase 3, but have no legend, so the wiki doesn't read them as HDLs (source page).
Moon Base relevance¶
Not established by the sources so far. The Users Guide's Phase 1 cargo-transportation target, "Deployment of landers with two metric ton cargo delivery capability to the lunar South Pole region" (Users Guide, p. 10), names no lander. The HDL is not treated as that lander.
- The wiki's match, by acronym, no phase: the "HDL Programs" in the Building the Moon Base fact sheet's list of commercial roles, for heavy cargo "beyond Artemis V" (above). The fact sheet doesn't expand "HDL" or tie it to a phase.
- The wiki's match, by name, no phase: the Moon Base Program's Ignition deck lists "Human-class Delivery Landers" and "HDL" among the programs "Focused On Building the Moon Base", for large cargo (above).
Related pages¶
Elements · Transportation Systems · Human Landing System · Lunar Surface Cargo Lander · CLPS · Pressurized Rover · Foundational Exploration · Lunar Surface Cargo
Sources¶
ADD Rev C, pp. 47, 56, 59, 148–156 · Users Guide, pp. 8–10 · Lunar objective decomposition, allocation sheets · Lunar Surface Cargo, pp. 2–3, 6 · Building the Moon Base fact sheet, pp. 1–2 · 2023 executive overview, PDF p. 10 · 2024 executive overview, PDF p. 24