NASA Struggling with Construction of Second Artemis Mobile Launcher

NASA’s Inspector General recently came to some scathing conclusions about the effort to build a second mobile launcher to support future launches of the Space Launch System. “In the nearly 3 years since NASA awarded the ML-2 contract, Bechtel (the primary contractor) has experienced numerous challenges, resulting in projected (contract) costs more than doubling to $960.1 million and the delivery schedule slipping at least 2.5 years to October 2025. NASA finds itself in this precarious position because the contractor severely underestimated the scope and complexity of the project, from labor hours to material and equipment costs to subcontracting,” the IG said.

The Mobile Launcher carries the Space Launch System from the Vehicle Assembly Building to the launch pad on top of the Crawler. (Photo from

The next block of SLS will have a new upper stage to allow
NASA to send more cargo to the Moon in a single launch. This
presents significantly different interfaces than with Mobile Launcher 1; hence, NASA’s need for Mobile Launcher 2. The new upper stage and structural adapters extend the SLS by 40 feet, so the critical swing arms for the launcher must be located at different elevations. The new upper stage also requires two new swing arms be added to the launcher. Additionally, the next versions of SLS will be taller, wind will have a greater effect on the rocket, which will impart higher loads on the launcher.

Figure from NASA Inspector General.

NASA has used mobile launcher platforms since the 1960s to launch spacecraft. These platforms enable NASA to assemble and process launch vehicles in the massive Vehicle Assembly Building before the crawler-transporter moves the platform out to the launch pad. The mobile launcher that will be used to support the first three Artemis flights was originally built for the program preceding Artemis known as Constellation. But it needed significant modifications to support the larger SLS system.

That effort faced its own struggles, costing more than $300 million to build than anticipated and running more than 3 years behind schedule. The Mobile Launcher 1 program experienced numerous design errors, requirements changes and challenges fabricating the connections known as umbilicals that provide power, communications, oxygen, and fuel. The IG said that NASA exacerbated these issues by accepting unproven and untested designs from contractors. The Government Accountability Office reported similar findings about Mobile Launcher 1.

NASA planned to incorporate lessons learned from developing the first launcher into the acquisition of the second. But the IG reported in its new report that the contractor for Mobile Launcher 2, Bechtel, was reluctant to incorporate lessons learned or use NASA’s expertise. In addition, Bechtel underestimated the overall scope and complexity of designing and building the launcher. It has also struggled to contain weight growth, allowing it to increase almost 1 million pounds. The IG also highlighted problems with contractor staffing turnover and retention, cost tracking, and risk management.

However, “while the majority of the problems experienced by the ML-2 project can be attributed to Bechtel’s poor performance, NASA is not without fault,” the IG noted. Unstable requirements for the next versions of SLS have hindered the effort and NASA only rated Bechtel’s performance as unsatisfactory for one award fee period, allowing it to collect nearly $3 million for its performance. Though NASA and Bechtel have since taken action to put the program on a better footing, it seems that program management weaknesses for Artemis still persist, increasing the risk of cost increases and delays for the U.S. effort to get back to the moon.

Additional sources of information:

Final Report – IG-22-012 – NASA’s Management of the Mobile Launcher 2 Contract

Mobile Launcher Tower Umbilicals and Accessories Fact Sheet (

Mobile Launcher 2 Fact Sheet (


GAO-19-716T, NASA: Actions Needed to Improve the Management of Human Spaceflight Programs

GAO-21-105, NASA HUMAN SPACE EXPLORATION: Significant Investments in Future Capabilities Require Strengthened Management Oversight

NASA’s second mobile launcher is too heavy, years late, and pushing $1 billion | Ars Technica

NASA audit reveals massive overruns in SLS mobile launch platform – SpaceNews

This entry was posted in NASA, Space Launch System and tagged , , . Bookmark the permalink.

2 Responses to NASA Struggling with Construction of Second Artemis Mobile Launcher

  1. I was more than happy to uncover this great site. I wanted to thank you for your time for this wonderful read!! I definitely liked every little bit of it and I have you book-marked to see new things on your blog.

Comments are closed.