22.04.2021

Following a year of testing and development, NASA recently selected SpaceX’s Starship-based Human Landing System (HLS) to land astronauts on the moon under the Artemis program. SpaceX’s proposal was the highest rated and lowest cost offering among three studied designs, the others provided by Blue Origin’s National Team and Dynetics.

In contrast to NASA’s stated wish for multiple Human Landing Systems, only one design was selected for an initial uncrewed demonstration and the first crewed landing, due to significant budget constraints. The offerings from Blue Origin, Dynetics, and other companies not previously studied for HLS, may thus continue development in hopes of being on-ramped for future recurring missions to the surface of the moon.

SpaceX was selected for an HLS Option A award, which calls for a demonstration of aggregation of the various elements of the system, docking the lander to the Orion spacecraft, transfer of crew from Orion to the lander in lunar orbit, conducting an Extravehicular Activity (EVA) after landing, and returning the crew and other materials from the surface. This included both an uncrewed and a crewed demonstration mission.

Similar to the Commercial Crew program tasked with delivering astronauts to the International Space Station (ISS), NASA aims to facilitate development of a multi-user transportation system for the moon. That is, NASA wants to be one of multiple customers to eventually utilize the vehicle designs produced from the HLS program.

Similarly, NASA wants to use multiple dissimilar vehicles for moon landings, as they have for ISS logistics. However, funding allocated to the HLS program was not sufficient to cover any one offeror’s proposed bid price. The source selection statement justifying NASA’s award decision states that “while it remains the Agency’s desire to preserve a competitive environment at this stage of the HLS Program, at the initial prices and milestone payment phasing proposed by each of the Option A offerors, NASA’s current fiscal year budget did not support even a single Option A award.”

NASA’s pair of Commercial Crew vehicles, Boeing Starliner (left) and SpaceX Crew Dragon (right), have set a precedent for redundant, commercial access to space – render via Mack Crawford for NSF/L2

SpaceX’s total evaluated price for their proposal was $2,941,394,557. While exact price figures are not provided for offerors that are not selected, the statement specifies that Blue Origin’s proposal was significantly more expensive than SpaceX, and that Dynetics’ proposal was significantly more expensive than Blue Origin.

Since SpaceX’s proposal was the lowest cost, ad also highly rated from technical and managerial perspectives, NASA chose to open price negotiations that could enable the agency to afford to develop the Starship HLS. SpaceX was able to revise the milestone payment timeline to fit within NASA’s current budget, although the overall price of the program was not reduced. SpaceX was not permitted to alter any technical aspects of their proposal during negotiations.

SpaceX selected for initial landings

SpaceX’s winning proposal is not without risk, but Starship offered several significant strengths that sufficiently offset any weaknesses. NASA’s evaluated SpaceX’s HLS proposal as a credible technical response to the agency’s needs, with any weaknesses either offset by strengths of inconsequential to contract performance.

Notable strengths of the Starship HLS design include a 100 day loiter capability in lunar orbit, exceeding NASA’s goal of a 90 day loiter period. The ability to wait at the moon for the arrival of the crew offers additional flexibility for Space Launch System (SLS) launches.

An unsurprising strength of the Starship architecture is the vehicle’s scale, significantly larger than others proposed. The upmass and downmass capacity far exceeded NASA’s requirements, so much so that the amount of cargo that can return to Earth is not limited by Starship, but rather what can be returned on the Orion crew vehicle. The large downmass capability is still valuable for delivering one-way payloads to the surface, which will facilitate greater science returns and a sustainable presence on the surface.

Orion docks to the Starship HLS. The lander design has been altered recently, including changes to the landing legs and thrusters, as well as the solar panels – via Mack Crawford for NSF/L2

The Starship design also supports a greater number of EVAs for longer durations than required. While the scale of Starship did present some relatively minor risks, including airlocks and windows located high off the moon’s surface, these were offset by the many benefits of such a large scale lander.

NASA also commended the robust abort and contingency plans available with Starship. The vehicle’s excess propellant margin can be applied to expedite an emergency ascent, and the design features both engine-out capability and redundant airlocks.

A focus of the HLS solicitation was also the ability to evolve vehicles to operate sustainably, using reusable vehicles that can be refueled and serve as useful habitation assets on the surface. Starship, in its initially proposed design, can act as a habitat for four crew members without relying on any pre-placed assets, and will not need any significant redesign work to meet NASA’s long term sustainability goals.

There is one area within which NASA found weaknesses with SpaceX’s proposal. The Starship architecture relies heavily on refueling in low Earth orbit (LEO), which complicates the company’s concept of operations. Plans call for a propellant tanker in LEO to be fueled my multiple Starship missions prior to the HLS Starship launching to refuel from that tanker and depart for the moon.

By launching the lander after the fuel has been delivered to orbit, risk to the time critical lander is mitigated, as well as schedule risks for the crew to be launched on Orion and SLS. Other minor risks identified during the HLS study period are mitigated by an aggressive testing plan, which is already underway at SpaceX’s facilities in Boca Chica, Texas, the site of multiple Starship flight tests to date.

NASA rated SpaceX’s HLS management structure as “outstanding,” citing the company’s plan to self-fund more than half of development and testing. SpaceX is developing Starship for multiple markets, which aligns with NASA’s commercialization goals and reduces price.

The agency also acknowledged strong insight into Starship testing activities provided by SpaceX. NASA teams, including the HLS program, have been heavily involved in Starship testing in Boca Chica.

Since Starship development originated as a Mars vehicle, with several other capabilities also in development for Earth orbit and other destinations, development would in all likelihood have continued in the absence of an HLS award. However, capabilities specifically requested for NASA’s Artemis program may have been omitted, or SpaceX could have descoped lunar surface missions entirely if a lack of other customers developed. Starship is also an eligible vehicle for uncrewed landings under NASA’s Commercial Lunar Payload Services (CLPS) program, but has not yet been awarded any CLPS task orders.

By awarding SpaceX a Starship HLS contract, NASA has ensured their voice will be heard during development, while strengthening a connection with the vehicle which may enable future missions to Mars. From SpaceX’s perspective, this award enables collaboration with experience NASA teams that will greatly improve the chances of success for the Starship program.

The future of Blue Origin, Dynetics, and others

The National Team led by Blue Origin and the proposal from Dynetics were not selected for Option A awards, due to a combination of lower technical ratings and budgetary constraints.

There were strengths with both designs. For example, Blue Origin’s ascent element was powered by three engines, but was operable under only two in an engine-out scenario. This, combined with the ability to separate elements, offered additional abort and contingency capabilities. The Dynetics single stage design, with a low to the surface crew module, was also of good merit.

A pair of Artemis crew members conduct an EVA outside the Dynetics HLS – render via Mack Crawford for NSF/L2

However, these were largely overshadowed by significant weaknesses with both designs. Immature propulsion and communications systems, along with concerns about third party suppliers, “create serious doubt as to the realism of Blue Origin’s proposed development schedule,” according to the source selection statement.

NASA also expressed concerns about crew scheduling, citing long crew days during descent and ascent to and from the lunar surface. This included a requirement for an EVA prior to liftoff in order to jettison materials to reduce the mass of the ascent element.

Blue Origin’s notional plan for evolving their HLS design into a more sustainable architecture called for significant redesigns, including a resized ascent element and a complete structure redesign and BE-7 engine upgrade for the descent element.

NASA did acknowledge that Blue Origin was effectively leveraging the experience of their National Team partners at Lockheed Martin, Northrop Grumman, and Draper. While this approach does take advantage of technical expertise, it is not necessarily conducive to cost effectiveness. This may relate to another weakness identified by NASA in that Blue Origin did not provide a comprehensive plan to operate their vehicle commercially.

Blue Origin revealed their Blue Moon program, from which their HLS descent element is based, as a commercial uncrewed and crewed lander prior to the HLS solicitation. Blue Moon is also an eligible CLPS vehicle. It is possible that a vehicle developed entirely by Blue Origin, rather than the National Team, would be proposed for future missions and be more susceptible to commercialization.

Blue Origin’s descent element launches aboard the company’s New Glenn rocket – render via Mack Crawford for NSF/L2

Beyond the technical evaluation of Blue Origin’s design, the proposal was effectively disqualified due to advance payments proposed that render the bid ineligible for award. Blue Origin proposed two kickoff meeting-related payments that would need to be eliminated through negotiations and a revised proposal to comply with the HLS solicitation.

If awarded a contract, further negotiations would have also been needed for NASA to secure data rights required by the HLS program. Blue Origin proposed to deliver some data sets with limited licenses, with no justification provided. This contradicted the requirements of the HLS solicitation and would require correction while on contract.

Under these circumstances, Blue Origin was not selected. However, NASA did consider entering negotiations for a lower price point which could improve the value of the proposal. This would have included the mandatory correction of the proposed advance payments.

This option was not pursued, as even a negotiated price point would not enable two HLS proposals to be selected. The SpaceX proposal was higher rated and lower cost to start, so negotiations with Blue Origin could not be completed in good faith.

Since NASA still wants to operate multiple lunar landers, plans are in work to create a program for recurring missions to the surface, with the ability to on-ramp new vehicles in the future. While SpaceX will be well positioned for these missions following the two demonstration missions now on contract, providers such as Blue Origin, Dynetics, or new entrants could rejoin the Artemis program for recurring missions.

This is supported by NASA’s positive assessment of Dynetics’ strong plan for commercialization. Weaknesses of the Dynetics proposal were mostly technical, including serious mass growth concerns and problems with the demonstration mission schedule. With time now to address the technical concerns as development continues, Dynetics could be positioned for future missions to the moon either with NASA under Artemis or with commercial customers.

Even for SpaceX’s HLS design, now under contract with NASA, significant work remains to be done before humanity’s return to the surface of the moon. But pending a rigorous test campaign, already underway, Starship is in position to begin what will hopefully become a permanent human presence in deep space, supported by additional vehicles in partnership with NASA, commercial companies, and international partners.

As Artemis sets foot on the moon, both NASA and SpaceX are also preparing to cooperatively pave the road for human missions to Mars.

Quelle: NS