from the still-would-be-throwing-them-away dept.
NASA could use an engine developed by Blue Origin instead of the four RL-10 engines currently used by the Space Launch System (SLS):
[One] problem with legacy hardware, built by traditional contractors such as Orbital ATK and Aerojet Rocketdyne, is that it's expensive. And while NASA has not released per-flight estimates of the expendable SLS rocket's cost, conservative estimates peg it at $1.5 to $2.5 billion per launch. The cost is so high that it effectively precludes more than one to two SLS launches per year.
[...] [The RL-10] engines, manufactured by Aerojet Rocketdyne, are also costly. (Ars understands that NASA paid an average of $17 million for each RL-10 engine for the maiden Exploration Upper Stage vehicle). So in October, to power the EUS, the space agency issued a request for information to the aerospace community for "a low cost drop-in replacement engine to minimize program cost." According to the document, the initial set of four engines would be needed in mid-2023 to prepare for the third flight of the SLS rocket, known as Exploration Mission-3.
Then, after an extension of the deadline for responses beyond mid-November, NASA revised the RFI on December 1. The revised document no longer seeks a "drop-in replacement" for the RL-10 engine, rather it asks for a "low-cost replacement engine." Although this seems like a subtle change, sources within the aerospace industry indicated to Ars that it is significant. According to NASA, it was done to increase the number of responses.
[...] That would probably include Blue Origin's BE-3U engine, which the company plans to use for its upper stage on the New Glenn heavy lift rocket. This is a modified version of the BE-3 engine that powers the New Shepard rocket, which has now flown successfully seven times. Blue Origin has previously marketed the BE-3U to Orbital ATK for its Next Generation Launch System, which is looking for an upper stage engine. A single BE-3U provides about 120,000 pounds of thrust, which exceeds the 100,000 pounds of thrust provided by four RL-10 engines.
Just cancel SLS and give that money to SpaceX, Blue Origin, or anybody willing to launch competitively.
Related: Maiden Flight of the Space Launch System Delayed to 2019
First SLS Mission Will be Unmanned
Commercial Space Companies Want More Money From NASA
Trump Space Adviser: Mars "Too Ambitious" and SLS is a Strategic National Asset
Boeing CEO Says His Company Will Carry Humans to Mars Before SpaceX
President Trump Signs Space Policy Directive 1
Related Stories
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.
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
Also at:
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
Previously: SpaceX to Fly Two Tourists Around the Moon in 2018
Maiden Flight of the Space Launch System Delayed to 2019
SpaceX might beat SLS to the moon with humans.
Commercial space companies want NASA to expand the Commercial Orbital Transportation Services program. SpaceX's senior vice president for global business and government affairs called for the COTS program to be extended to deep space activities:
Commercial space companies today (July 13) urged legislators to extend NASA's successful public-private partnerships for International Space Station transportation to future programs, including human missions to Mars.
NASA already is working with six firms to develop prototype habitats that would augment the agency's multibillion-dollar Orion capsule and Space Launch System heavy-lift rocket. NASA has said it intends to use the system to send astronauts to Mars in the 2030s.
[...] Technologies that SpaceX would be interested in developing in partnership with NASA include heavy-cargo missions to Mars, deep-space communications systems, and demonstrations of vertical takeoff and landing on the moon, Hughes said.
Getting spacecraft like the Interplanetary Spaceship to Mars will probably require SpaceX to dip into the NASA coffers yet again:
This proposal was foreshadowed last year in Guadalajara, Mexico. At the International Astronautical Congress there, Musk presented a sketch of the architecture needed to lower the cost of transit to Mars enough to make colonization feasible. His top-line cost of $10 billion, however, is likely out of reach for SpaceX in the near term—without the help of a big-pocketed government. "There's a lot of people in the private sector who are interested in helping fund a base on Mars, and perhaps there will be interest on the government sector side to do that," Musk said last fall.
Also at Ars Technica and LA Times (broader article about the economics of heavy launch capabilities).
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
Who will make it to Mars first?
It was about a year ago that Boeing Chief Executive Dennis Muilenburg first began saying his company would beat SpaceX to Mars. "I'm convinced that the first person to step foot on Mars will arrive there riding on a Boeing rocket," he said during a Boeing-sponsored tech summit in Chicago in October 2016.
On Thursday, Muilenburg repeated that claim on CNBC. Moreover, he added this tidbit about the Space Launch System rocket—for which Boeing is the prime contractor of the core stage—"We're going to take a first test flight in 2019 and we're going to do a slingshot mission around the Moon."
Unlike last year, Muilenburg drew a response from SpaceX this time. The company's founder, Elon Musk, offered a pithy response on Twitter: "Do it."
The truth is that Boeing's rocket isn't going anywhere particularly fast. Although Muilenburg says it will launch in 2019, NASA has all but admitted that will not happen. The rocket's maiden launch has already slipped from late 2017 into "no earlier than" December 2019. However, NASA officials have said a 2019 launch is a "best case" scenario, and a slip to June 2020 is more likely.
#SLS2020
Also, the next SpaceX flight is an ISS resupply mission and is scheduled for this coming Tuesday (December 12, 2017) at 1646 GMT (11:46 a.m. EST) from SLC-40, Cape Canaveral Air Force Station, Florida. The plan is for the booster to return to landing at Landing Zone-1, also at Cape Canaveral.
Previously: Maiden Flight of the Space Launch System Delayed to 2019
Elon Musk Publishes Mars Colonization Plan
SpaceX Appears to Have Pulled the Plug on its Red Dragon Plans
SpaceX Putting Red Dragon on the Back Burner
SpaceX: Making Human Life Multiplanetary
Related: VP of Engineering at United Launch Alliance Resigns over Comments About the Space Launch Industry
ULA Exec: SpaceX could be Grounded for 9-12 Months
Commercial Space Companies Want More Money From NASA
Bigelow and ULA to Put Inflatable Module in Orbit Around the Moon by 2022
SpaceX Unlocks "Steamroller" Achievement as Company Eyes 19 Launches in 2017
Trump Space Adviser: Mars "Too Ambitious" and SLS is a Strategic National Asset
SpaceX's Reusable Rockets Could End EU's Arianespace, and Other News
No more sending humans to an asteroid. We're going back to the Moon:
The policy calls for the NASA administrator to "lead an innovative and sustainable program of exploration with commercial and international partners to enable human expansion across the solar system and to bring back to Earth new knowledge and opportunities." The effort will more effectively organize government, private industry, and international efforts toward returning humans on the Moon, and will lay the foundation that will eventually enable human exploration of Mars.
"The directive I am signing today will refocus America's space program on human exploration and discovery," said President Trump. "It marks a first step in returning American astronauts to the Moon for the first time since 1972, for long-term exploration and use. This time, we will not only plant our flag and leave our footprints -- we will establish a foundation for an eventual mission to Mars, and perhaps someday, to many worlds beyond."
The policy grew from a unanimous recommendation by the new National Space Council, chaired by Vice President Mike Pence, after its first meeting Oct. 5. In addition to the direction to plan for human return to the Moon, the policy also ends NASA's existing effort to send humans to an asteroid. The president revived the National Space Council in July to advise and help implement his space policy with exploration as a national priority.
President's remarks and White House release.
Presidential Memorandum on Reinvigorating America's Human Space Exploration Program
Also at Reuters and New Scientist.
Previously: Should We Skip Mars for Now and Go to the Moon Again?
How to Get Back to the Moon in 4 Years, Permanently
NASA Eyeing Mini Space Station in Lunar Orbit as Stepping Stone to Mars
NASA and Roscosmos Sign Joint Statement on the Development of a Lunar Space Station
Bigelow and ULA to Put Inflatable Module in Orbit Around the Moon by 2022
Aerojet Rocketdyne wants the U.S. Air Force to contribute more funding for the development of its AR1 rocket engine. But that may be a hard sell when the mostly privately funded BE-4 from Blue Origin is close to being ready to fly:
In recent years, Aerojet has sought funding from the US Air Force to design and build the AR1, which has approximately 20 percent more thrust than a space shuttle main engine. The Air Force, in turn, has pledged as much as $536 million in development costs provided that Aerojet puts its own skin in the game—about one-third of research and development expenses.
According to a new report in Space News, Aerojet is now saying that even this modest investment is too much, and the company is seeking to reduce its share of the development costs from one-third to one-sixth. "As we look to the next phase of this contract, we are working with the Air Force on a smart and equitable cost-share," Aerojet spokesman Steve Warren told the publication. "We are committed to delivering an engine in 2019."
According to the report, the Air Force is not inclined to renegotiate the agreement. The Air Force's hesitation to increase its investment is probably because the military may not really need the AR1 rocket engine any more due to the emergence of Blue Origin, the rocket company founded by Amazon founder Jeff Bezos.
Related: Blue Origin Will Build its Rocket Engine in Alabama
NASA Opens Door to Possibly Lowering SLS Cost Using Blue Origin's Engines
After the Falcon Heavy Launch, Time to Defund the Space Launch System?
NASA's nearly billion-dollar mobile launcher tower for the Space Launch System (SLS) is leaning, and may be discarded after a single use:
[The "mobile launcher" component] supports the testing and servicing of the massive SLS rocket, as well as moving it to the launch pad and providing a platform from which it will launch.
According to a new report in NASASpaceflight.com, the expensive tower is "leaning" and "bending." For now, NASA says, the lean is not sufficient enough to require corrective action, but it is developing contingency plans in case the lean angle becomes steeper.
These defects raise concerns about the longevity of the launch tower and increase the likelihood that NASA will seek additional funding to build a second one. In fact, it is entirely possible that the launch tower may serve only for the maiden flight of the SLS rocket in 2020 and then be cast aside. This would represent a significant waste of resources by the space agency.
[...] [From] the tower's inception in 2009, NASA will have spent $912 million on the mobile launcher it may use for just a single launch of the SLS rocket. Moreover, the agency will have required eight years to modify a launch tower it built in two years.
The second mobile launcher, intended for larger versions of the SLS, will cost about $300 million (if not more).
Related: Maiden Flight of the Space Launch System Delayed to 2019
Trump Space Adviser: Mars "Too Ambitious" and SLS is a Strategic National Asset
NASA Opens Door to Possibly Lowering SLS Cost Using Blue Origin's Engines
After the Falcon Heavy Launch, Time to Defund the Space Launch System?
Blue Origin's orbital rocket in the running to receive U.S. military investment
Blue Origin submitted a proposal late last year in what's expected to be a four-way competition for U.S. Air Force funding to support development of new orbital-class rockets, a further step taken by the Jeff Bezos-owned company to break into the military launch market, industry officials said. The proposal, confirmed by two space industry sources, puts Blue Origin up against SpaceX, Orbital ATK and United Launch Alliance, which could use Blue Origin's BE-4 engine to power its next-generation Vulcan rocket. It also sets up the New Glenn rocket, in development by Blue Origin, to be certified by the Air Force for national security missions.
Blue Origin received funding in an earlier phase of the Air Force's initiative to help companies develop new liquid-fueled U.S.-built booster engines in a bid to end the military's reliance on the Russian RD-180 powerplant, which drives the first stage of ULA's Atlas 5 rocket. The Air Force's money supported development of the BE-4 engine, which was designed with private money, and is still primarily a privately-funded program. The Pentagon funding announced in early 2016 for the BE-4 program was directly awarded to ULA, which routed the money to Blue Origin's engine program.
SpaceX, Orbital ATK and Aerojet Rocketdyne also received Air Force funding in 2016 for propulsion work. SpaceX used the Air Force money for its methane-fueled Raptor engine, which will power the company's next-generation super-heavy BFR launcher. Orbital ATK is developing its own launcher for national security missions, which would use solid-fueled rocket motors for the initial boost into space, then use a hydrogen-fueled upper stage for orbital injection. Aerojet Rocketdyne's AR1 engine is a backup option for ULA's new Vulcan rocket.
Previously: U.S. Air Force Awards SpaceX $40.7 Million for Raptor Engine Development
Aerojet Rocketdyne Seeks More U.S. Air Force Funding for AR1 Rocket Engine
Related: Jeff Bezos' Vision for Space: One Trillion Population in the Solar System
NASA Opens Door to Possibly Lowering SLS Cost Using Blue Origin's Engines
SpaceX BFR vs. ULA Vulcan Showdown in the 2020s
Jeff Bezos's rocket company beats out spaceflight veteran for engine contract
Jeff Bezos's Blue Origin rocket company just scored a major contract. His company's BE-4 engines will power United Launch Alliance's Vulcan Centaur, a new suite of rockets that will aim to better compete with Elon Musk's SpaceX on price. Its first launch is slated for 2020. The contract award with ULA marks a high-profile vote of confidence for Bezos's space startup.
"We are very glad to have our BE-4 engine selected by United Launch Alliance. United Launch Alliance is the premier launch service provider for national security missions, and we're thrilled to be part of their team and that mission," Blue Origin CEO Bob Smith said in a statement announcing the award on Thursday.
[...] Blue Origin's win does not come as a huge surprise. The BE-4 is further along in development than the comparable Aerojet engine, dubbed the AR1, and is expected to be less expensive to make. [ULA CEO Tory] Bruno previously expressed his preference for Blue's BE-4 over Aerojet's AR1.
BE-4.
Also at Ars Technica.
Related: Blue Origin Will Build its Rocket Engine in Alabama
NASA Opens Door to Possibly Lowering SLS Cost Using Blue Origin's Engines
Aerojet Rocketdyne Seeks More U.S. Air Force Funding for AR1 Rocket Engine
SpaceX BFR vs. ULA Vulcan Showdown in the 2020s
Blue Origin to Compete to Launch U.S. Military Payloads
SLS contractor gets real, says program needs to focus on "affordability"
For the most part, the presentations [at the American Astronautical Society's Wernher von Braun Memorial Symposium] went as usual for these kinds of events—corporate vice presidents talking about the progress they were making on this or that component of the rocket and spacecraft. Although the Space Launch System rocket is going to launch three years later than originally planned, and its program is over budget and was recently admitted by NASA's own inspector to be poorly managed, you would not have known it from these presentations.
However, one panelist did offer a warning of sorts to his colleagues. Former astronaut and Vice President and General Manager of Propulsion for Northrop Grumman Charlie Precourt spoke about his company's contributions to the rocket (Northrop Grumman recently acquired Orbital ATK). They are building the large, solid rocket boosters that will provide a kick off the launch pad. Yet Precourt prefaced his update with a message about affordability—as the exploration program moves from development into operations with the first flight of SLS and Orion in 2020 or so, costs must come down, he said.
[...] "We have to execute, but we also have to be planning for the future in terms of survivability, sustainability, and affordability," Precourt said. "I used all three of those words intentionally about this program. We've got to make sure we've got our mindset on affordability, and I don't think it's too early for all of us on this panel, as well as our counterparts at NASA, to start thinking about that."
[...] Precourt said contractors should consider a future in which NASA's present multibillion expenditures on rocket development costs need to be cut in half in order for the SLS vehicle to have a robust future. "All of us need to be thinking about [how] our annual budget for this will not be what it is in development," he said. "That's a very serious problem that we have to look forward to, and to try to rectify, so that we are sustainable."
If the other speakers had thoughts about Precourt's comments, they did not share them during the ensuing discussion.
Related: NASA Opens Door to Possibly Lowering SLS Cost Using Blue Origin's Engines
NASA Administrator Ponders the Fate of SLS in Interview
There's a New Report on SLS Rocket Management, and It's Pretty Brutal
Damage Control: Boeing-Sponsored Newsletter Praises Space Launch System (SLS), Trashes Saturn V
Blue Origin starts building the factory for New Glenn's engines
Blue Origin's New Glenn rocket just became more tangible. The company has officially started construction on a factory in Huntsville, Alabama that will produce the BE-4 engines powering both New Glenn and United Launch Alliance's Vulcan Centaur. It'll also make the BE-3U engines used for New Glenn's second stage. While it's not clear when the factory will start making rockets, Blue Origin expects to complete development later in 2019.
Both New Glenn and Vulcan Centaur are expected to launch in 2021.
BE-4.
Previously: Blue Origin Will Build its Rocket Engine in Alabama
NASA Opens Door to Possibly Lowering SLS Cost Using Blue Origin's Engines
Blue Origin to Compete to Launch U.S. Military Payloads
Blue Origin Wins Contract to Supply United Launch Alliance With BE-4 Rocket Engines
(Score: 2) by Runaway1956 on Monday December 18 2017, @02:46PM (3 children)
Depending on a person's level of sophistication, it's not really all that subtle a difference. In the first instance, Nasa was looking for an engine meeting all the same specifications, ie, "drop-in". In the latter instance, they are willing to shitcan their specifications, and are willing to consider any engine capable of accomplishing the mission. They save a zillion dollars if the new engines don't have to match physical dimensions, match existing plumbing, etc, etc, etc.
Want me to remodel your old delapidated house? It's gonna cost big money. Want me to just rebuild your old ramshackle dive? I can do that a helluva lot cheaper, and guarantee better results.
“I have become friends with many school shooters” - Tampon Tim Walz
(Score: 2) by bob_super on Monday December 18 2017, @05:39PM (2 children)
> Want me to remodel your old delapidated house? It's gonna cost big money.
> Want me to just rebuild your old ramshackle dive? I can do that a helluva lot cheaper
The more precise parallel would be that the new cooking range doesn't have to be the exact dimensions of the old one, it will be worth it even if we have to get some guys to adjust the countertops, electrical and gas pipes after all.
Since we throw away the range and the countertop after every meal instead of designing them to be washable, the threat of losing their cash cow could convince the current range supplier to lower their price...
(Score: 2) by Runaway1956 on Monday December 18 2017, @06:10PM (1 child)
You nailed it, bob_super. I couldn't stretch my mind far enough to consider throwing away the range and countertop after each use, but you nailed it.
“I have become friends with many school shooters” - Tampon Tim Walz
(Score: 2) by bob_super on Monday December 18 2017, @06:59PM
In their defense, except for that moment when they used the $500M/use non-stick pan, throwing away the range and countertop is what they've always done.
Some kid in the neighborhood claims you can reuse stuff, but since his newfangled "cleanable" kitchen blew up a few times, and the boss wants us to keep using our reliable disposable kitchens, it's hard to change minds. Nobody ever got fired for buying Boeing, you know.
(Score: 2) by DannyB on Monday December 18 2017, @02:56PM (2 children)
It's just so unfair! How will our poor downtrodden aerospace companies survive if the flow from the public teat is reduced?
Reduce costs? Very unreasonable indeed!
The SLS engines are EXACTLY the right thing. Just what we should be using. It is based on the SSME (space shuttle main engine). It is the best of both worlds. Take a very expensive re-usable engine, and put it on an expendable launcher. How can you possibly beat that for top revenue earner?
Don't put a mindless tool of corporations in the white house; vote ChatGPT for 2024!
(Score: 0) by Anonymous Coward on Monday December 18 2017, @03:02PM (1 child)
How can you possibly beat that for top revenue earner?
Easy, just keep moving the goal post so you can study the thing indefinitely and never actually have to make it work.
This is optimal both for cash flow to industry and hang around till retirement for the NASA 'engineers'.
(Score: 2) by Grishnakh on Monday December 18 2017, @05:17PM
NASA actually gets some stuff done now and then, especially when projects are smaller and can be completed within one Presidential Administration's lifetime. The big projects just go one forever without making any progress.
Where you really see this a lot is with military contracts.
(Score: 1, Interesting) by Anonymous Coward on Monday December 18 2017, @03:32PM (1 child)
Don't know about the physical size of these engines, but the modular SpaceX engine is (iirc) about 170,000 lbs of thrust. Modular because it has a computer(s) on the engine -- connects to the main rocket system with a network cable, some power cables and of course fuel/oxidizer plumbing.
When I had the short tour a few years back, their production line was spitting out an engine nearly every day (something like 200/year?) Each engine was on a pallet and the pallets were shifted to the next assembly station every day(?) They could probably spare a few for NASA...
(Score: 0) by Anonymous Coward on Monday December 18 2017, @03:45PM
X uses a different fuel?
(Score: 2) by Tara Li on Monday December 18 2017, @03:55PM (1 child)
Looks like 190,000 lb of thrust... Might be suitable.
(Score: 2) by takyon on Monday December 18 2017, @04:16PM
Or the upcoming BE-4 [arstechnica.com] which is set to be more powerful than SpaceX's Merlin or Raptor.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 0) by Anonymous Coward on Monday December 18 2017, @04:14PM
So... SLS block 1 uses a grand total of 1 of those RL-10s. Block 2 uses 4. Let's assume that $17 million price is correct, and they get the new engines for free. That's a cost savings of $17m (Block 1) or $68m (Block2) at maximum. So from $1.5 to $2.5 billion per launch it drops to $1.432 to $2.432 billion. Woo-hoo.
Of course, the new engines aren't free, so it's not even that, but what's an extra few million among lobbyists?
(Score: 5, Interesting) by khallow on Monday December 18 2017, @04:48PM (6 children)
There are other safety issues. When you light up a solid rocket, it usually stays lit till it burns out. Also the problem that fireballs resulting from break up of a solid rocket motor are larger and hotter than their liquid-fueled equivalents. Meaning a beefier (and higher acceleration) escape system (launch abort system or LAS in the nomenclature) needs to be used in order for astronauts to survive such accidents during launch.
The final problem is that solid rocket motors are less efficient. They tend to have decent thrust-mass ratios (which are important), but terrible mass fractions (meaning you need a higher fraction of propellant to empty mass) to get the same level of delta-v.
Liquid-fueled boosters (particularly, with LOX/kerosene propellant) would neatly bypass a large number of big problems. But it means less profit for the Orbital-ATK cookie monster who will makes the current SRMs.
For example, Wikipedia says the mass of a fully fueled [wikipedia.org] first stage of a block one vehicle is almost 1000 metric tons (979 metric tons) to put 70 tons in space. Most of that mass is propellant with 85 metric tons of support structure and plumbing. Most of the rest is solid rocket propellant. The Shuttle SRBs are 590 metric tons. These are going to be about 25% larger (with some slight reduction in dead mass), so maybe 700-750 metric tons or so, just due to the SRMs (the rest is fluffier due to the use of liquid hydrogen in place of kerosene as fuel).
Sorry, it's a vehicle with very poor first stage specifications due to the insistence on solid propellant and LOX/liquid hydrogen. They could instead use LOX/kerosene for all of the rockets and get similar thrust-weight and better specific impulse (better mass fractions). They also wouldn't need to build a new crawler or hope the VAB never gets destroyed in an SRM-caused accident.
As an aside, if they're shopping around for a cheaper first stage rocket engine now, then they aren't going to launch in 2019. Expect further delays.
(Score: 3, Insightful) by takyon on Monday December 18 2017, @04:59PM (1 child)
Actually, it's pretty much guaranteed to slip to the middle of 2020. From a December 2019 launch date, so it was barely hanging in there. So we should begin thinking about how it could slip into 2021-2022 (and hopefully get cancelled entirely).
SLS rocket advancing, but its launch date may slip to 2020 [arstechnica.com]
SLS managers rally the troops to avoid EM-1 slip into 2020 [nasaspaceflight.com]
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2, Insightful) by khallow on Monday December 18 2017, @06:07PM
Else we'll get very expensive projects which will "suck the oxygen out of the room". It's the Space Shuttle all over again.
(Score: 2) by Grishnakh on Monday December 18 2017, @05:36PM (1 child)
I thought the whole point of using SRBs was to save money, because solid rockets are really cheap, and an inexpensive way of providing a lot of thrust, even if the mass fraction is poor, as long as you don't need to throttle it. So for this reason, I can see why they used them on the Space Shuttle, just for the initial launch to get the vehicle off the ground and up to speed, and then jettisoning them. However, using overly complex and expensive SSMEs burning LH2 seems to negate the cost advantages.
(Score: 2, Interesting) by khallow on Monday December 18 2017, @06:04PM
That's not the first time that has happened in an aerospace project. That Congress went gung-ho on this project despite the cost savings not matching the cost losses indicates, yet again, that the primary purpose wasn't to save any money.
Moving on, currently, they're looking at building, for the block 2, four liquid-fueled rocket engines anyway. So why not just build more of those rocket engines (say with their own copy of the first stage), and do away with that unnecessary logistics and operational complexity (Well, aside from the pork ecosystem, that is)? That's what Delta IV Heavy and Falcon Heavy did.
(Score: 1) by khallow on Monday December 18 2017, @06:05PM (1 child)
(Score: 1) by khallow on Monday December 18 2017, @06:09PM