The House version of the fiscal year 2021 spending bill calls for launching Europa Clipper on SLS only if an SLS is available.
Europa Clipper Level 1 science requirements will be modified to reduce the mission’s reliance on MASPEX and to reduce MASPEX performance requirements.
There are launch opportunities in summer and fall 2024 for Europa Clipper, including an August 2024 window using the Space Launch System that would send the spacecraft directly to Europa.
Europa Clipper has a launch readiness date of 2024, which is one year later than plans announced the previous year.
The Europa Clipper program has an agency cost commitment of $4,250,000,000.
A House appropriations bill introduced 2020-07-07 conditions Europa Clipper launching on SLS only 'if available', granting NASA some flexibility compared with previous spending bills.
An October 2024 launch window for Europa Clipper would require Mars and Earth gravity assists, extending flight time, and could be executed by commercial launch vehicles such as SpaceX’s Falcon Heavy.
The fiscal year 2020 appropriations bill directed use of SLS for Europa Clipper but pushed the launch date to no later than 2025.
Europa Clipper met a JPL recommendation of 25% unallocated future expenses (UFE) after completing a final delta preliminary design review in June 2019.
Europa Clipper passed Key Decision Point C in August 2019, at which NASA set a baseline cost of $4,250,000,000 covering development and operations.
Russell Vought wrote that using a commercial launch vehicle instead of SLS would provide over $1,500,000,000 in cost savings for the Europa Clipper launch.
A follow-up OIG letter in August concluded NASA could save up to $1,000,000,000 by launching Europa Clipper on a commercial vehicle instead of the SLS and that NASA needed to decide how to launch the mission within months to support a potential 2023 launch.
NASA's letter to Congress urges the removal of the requirement to launch the Europa Clipper on an SLS.
Placing Europa Clipper into storage for two years, assuming spacecraft completion in 2023, will incur costs of an estimated $3 million to $5 million per month.
Launching Europa Clipper in 2023 would save $250 million from the estimated total cost of $4.25 billion.
The Office of Inspector General's audit from May warned of cost and schedule problems for the Europa Clipper program.
United Launch Alliance plans to phase out the Delta 4 Heavy around the time the Europa Clipper is expected to launch.
Europa Clipper passed a review known as Key Decision Point C, which established cost and schedule baselines for the mission.
NASA’s fiscal year 2020 budget request proposed using a commercial launch vehicle such as Delta IV Heavy or Falcon Heavy to launch Europa Clipper to save several hundred million dollars while increasing transit time to about seven years.
Appropriations bills for fiscal year 2019 and prior years directed NASA to use the Space Launch System for Europa Clipper.