The first launch of the SLS has slipped again:
NASA has decided it must delay the maiden flight of its Space Launch System rocket, presently scheduled for November 2018, until at least early 2019. This decision was widely expected due to several problems with the rocket, Orion spacecraft, and ground launch systems. The delay was confirmed in a letter from a NASA official released Thursday by the US Government Accountability Office.
The Falcon Heavy will be able to deliver payloads that are similar to what SLS Block 1 can carry:
In its maiden flight configuration, named Block 1, the heavy-lifter will be able to haul up to 77 tons (70 metric tons) of cargo to low Earth orbit, more than double the capacity of the most powerful launcher flying today — United Launch Alliance's Delta 4-Heavy. The Block 1 version of SLS will fly with an upper stage propelled by an Aerojet Rocketdyne RL10 engine, based on the Delta 4's second stage.
SpaceX's Falcon Heavy rocket, scheduled to make its first flight later this year, will come in just shy of the SLS Block 1's capacity if the commercial space company gave up recovering its booster stages.
NASA plans to introduce a bigger four-engine second stage on the EM-2 launch, a configuration of the SLS named Block 1B.
In recent months, the executive secretary of the National Space Council, Scott Pace, has worked assiduously behind the scenes to develop a formal space policy for the Trump administration. In a rare interview, published Monday in Scientific American, Pace elaborated on some of the policy decisions he has been helping to make.
In the interview, Pace explained why the Trump administration has chosen to focus on the Moon first for human exploration while relegating Mars to becoming a "horizon goal," effectively putting human missions to the Red Planet decades into the future. Mars was too ambitious, Pace said, and such a goal would have precluded meaningful involvement from the burgeoning US commercial sector as well as international partners. Specific plans for how NASA will return to the Moon should become more concrete within the next year, he added.
In response to a question about privately developed, heavy-lift boosters, the executive secretary also reiterated his skepticism that such "commercial" rockets developed by Blue Origin and SpaceX could compete with the government's Space Launch System rocket, which is likely to make its maiden flight in 2020. "Heavy-lift rockets are strategic national assets, like aircraft carriers," Pace said. "There are some people who have talked about buying heavy-lift as a service as opposed to owning and operating, in which case the government would, of course, have to continue to own the intellectual properties so it wasn't hostage to any one contractor. One could imagine this but, in general, building a heavy-lift rocket is no more 'commercial' than building an aircraft carrier with private contractors would be."
I thought flying non-reusable pork rockets was about the money, not strategy. SpaceX is set to launch Falcon Heavy for the first time no earlier than December 29. It will have over 90% of the low Earth orbit capacity as the initial version of the SLS (63.8 metric tons vs. 70).
Previously: Maiden Flight of the Space Launch System Delayed to 2019
First SLS Mission Will be Unmanned
Commercial Space Companies Want More Money From NASA
U.S. Air Force Will Eventually Launch Using SpaceX's Reused Rockets
A government watchdog is warning that the launch of the James Webb Space Telescope (JWST), the long-awaited successor to the Hubble that's been beset by schedule snafus and cost overruns, might face further delays. NASA announced in September it had pushed back the launch date of the JWST from late 2018 to some time in the spring of 2019 due to testing delays partly blamed on Hurricane Harvey's impact on Texas' Gulf Coast in August.
On Wednesday, lawmakers on the House Science, Space and Technology Committee were told it could take even longer to launch the world's most powerful telescope. "More delays are possible given the risks associated with the work ahead and the level of schedule reserves that are now (below) what's recommended," said Cristina Chaplain, director of Acquisition and Sourcing Management for the Government Accountability Office.
[...] Thomas Zurbuchen, NASA's associate administrator for science missions, told lawmakers he expects the space agency will be able to meet the spring 2019 schedule. "I believe it's achievable," he said.
The first SLS flight, around the moon, will not include a crew.
The first flight of NASA's next-generation heavy-lift rocket, the Space Launch System (SLS), is now scheduled for 2019 and will not include a human crew, agency officials said today (May 12).
As of 2016, NASA had planned for the SLS' first flight to take place in 2018, without a crew on board. But the transition team that the Trump administration sent to the agency earlier this year asked for an internal evaluation of the possibility of launching a crew atop the SLS inside the agency's Orion space capsule.
Robert Lightfoot, NASA's acting administrator, said during a news conference today that, based on the results of this internal evaluation, a crewed flight would be "technically feasible," but the agency will proceed with its initial plan to make the rocket's first flight uncrewed.
[...] SLS' first flight will be called Exploration Mission 1, or EM-1, and will send an uncrewed Orion capsule (which has already made one uncrewed test flight, aboard a United Launch Alliance Delta IV Heavy rocket) on a roughly three-week trip around the moon. The first crewed flight, EM-2, was originally scheduled to follow in 2021.
Source:NASA Won't Fly Astronauts On 1st Orion-SLS Test Flight Around the Moon
NASA Study Warns Against Putting Crew On Huge Rocket's First Flight
NASA Denies Trump's Request to Send Astronauts Past the Moon on New Rocket
SpaceX might beat SLS to the moon with humans.