Author Topic: Sierra Space Dream Chaser UPDATE Thread (was SNC)  (Read 740719 times)

Offline adrianwyard

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Re: SNC Dream Chaser UPDATE Thread
« Reply #560 on: 04/19/2015 05:12 pm »

Does anyone really feel that Dreamchaser will ever get finished?

I think that's still very much up in the air at the moment.

Actually, up in the air would be a step in the right direction ... for a lifting-body...
« Last Edit: 04/19/2015 05:13 pm by adrianwyard »

Offline Patchouli

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Re: SNC Dream Chaser UPDATE Thread
« Reply #561 on: 04/21/2015 02:56 am »

Actually, up in the air would be a step in the right direction ... for a lifting-body...


Pretty much is for any spacecraft.

Still I hope it gets built as it's a very capable vehicle plus I feel landing like an aircraft is probably the safest and more practical way for a LEO crew vehicle to return.


Offline SWGlassPit

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Re: SNC Dream Chaser UPDATE Thread
« Reply #562 on: 04/21/2015 02:55 pm »

Actually, up in the air would be a step in the right direction ... for a lifting-body...


Pretty much is for any spacecraft.

Still I hope it gets built as it's a very capable vehicle plus I feel landing like an aircraft is probably the safest and more practical way for a LEO crew vehicle to return.



Landing like an aircraft has its advantages, but I would strongly disagree with calling it the safest.  That style of reentry and landing requires a much finer degree of control and has more failure modes than other methods. 

Offline adrianwyard

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Re: SNC Dream Chaser UPDATE Thread
« Reply #563 on: 04/21/2015 03:12 pm »
Parachutes+water landings will stay in the lead safety-wise for the foreseeable future, but if you wish to consider other EDL methods (because you value the advantages they bring sufficiently to trade a little safety) it's a really unclear to me what's the next best method.

For more see a poll and discussion here: http://forum.nasaspaceflight.com/index.php?topic=36856.msg1335263#msg1335263

Offline Patchouli

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Re: SNC Dream Chaser UPDATE Thread
« Reply #564 on: 04/22/2015 05:19 am »


Landing like an aircraft has its advantages, but I would strongly disagree with calling it the safest.  That style of reentry and landing requires a much finer degree of control and has more failure modes than other methods. 

I degree on the grounds that statistics says otherwise.
The avionics on a space plane are probably more reliable then everything else in a space transportation system as they're more or less the same kind of technology millions of people trust their lives with every day when they fly on a commercial jet.

The shuttle's two LOC events were stack interaction related vs a failure of the landing systems.
It had a fragile TPS ,no LAS, and was in the debris stream of the launch stack.
Other then the two accidents the shuttle has not caused any injuries esp during landing.

Since Dream Chaser sits on top of it's LV and has a LAS the type of LOC events that happened on STS 51L would not have been a loss of crew event and the failure that happened on STS 107 would be impossible as there are no tanks ahead of the vehicle to shed debris.

I think DC on Atlas V could in fact be one of the safest spacecraft designed so far.
When it lands it's at an airport vs in the middle of the ocean,or the wilderness.
One of these is a better situation to be in then the other two esp if the crew has been deconditioned from a long flight or a crew member needs medical attention.

« Last Edit: 04/22/2015 06:15 am by Patchouli »

Offline darkenfast

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Re: SNC Dream Chaser UPDATE Thread
« Reply #565 on: 04/22/2015 07:49 am »
CST-100 will land at somewhere like Edwards AFB, which is hardly wilderness.  Dragon will eventually transition to landing sites like the one at Vandenberg.  The lower G-forces of DC for long-term returnees will only be of benefit if the person is riding in a seat moved to the supine position, as was done on the Orbiter's mid-deck.  Have we seen any renderings showing that in the small DC cabin?  Both capsules have equipment to handle a degraded landing, such as three chutes or landing rockets backed up by chutes, plus water-landing capability, if needed.   
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Offline SWGlassPit

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Re: SNC Dream Chaser UPDATE Thread
« Reply #566 on: 04/22/2015 04:52 pm »

I degree on the grounds that statistics says otherwise.


There have not been enough space flights to make any sort of judgment with any real statistical significance.  Even at a fairly low confidence level, the margin of error with respect to the number of samples available is quite large.

Instead, you need to look at the designs themselves.  Capsules are more able to be made passively stable, which means they can still survive a reentry even with complete loss of attitude control -- see, e.g., the Soyuz ballistic reentry profile.  Even with the shuttle, the winged design meant that positive control had to be maintained at all times, as the vehicle could not withstand the aerodynamic forces if its angle of attack or sideslip angle went beyond a specific envelope.

Offline adrianwyard

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Re: SNC Dream Chaser UPDATE Thread
« Reply #567 on: 04/22/2015 05:00 pm »
That reminds me that we rarely acknowledge that the DC shape should be passively stable; the forces on those canted fins placing the center of lift above the center of mass. I suspect (but don't know) that DC could be even more stable than a capsule were it loaded with heavy cargo.
« Last Edit: 04/22/2015 05:01 pm by adrianwyard »

Offline adrianwyard

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Re: SNC Dream Chaser UPDATE Thread
« Reply #568 on: 06/15/2015 05:31 pm »
"Sierra Nevada Dream Chaser could make Huntsville the first commercial landing site for space craft"

http://www.al.com/news/index.ssf/2015/06/sierra_nevada_announcement.html

Local leaders this morning announced Huntsville will study feasibility of landing the Sierra Nevada Corporation's Dream Chaser spacecraft at Huntsville International Airport.

Depending on the results of the study, Huntsville could become the first commercial airport landing a space craft, Mayor Tommy Battle said at the announcement Monday morning.

The study will take about six months, and landings could begin as early as 2018 when Dream Chaser is expected to begin space flight. The spacecraft will launch to space on an Atlas rocket built by United Launch Alliance of Decatur.

"The Dream Chaser spacecraft is proposed by SNC in the current NASA competition to supply cargo to the International Space Station," a media advisory from the Chamber said last week. "SNC also plans to operate the vehicle on other missions, tailored to a variety of U.S. and International Customers."

Offline AnalogMan

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Re: SNC Dream Chaser UPDATE Thread
« Reply #569 on: 06/19/2015 11:41 pm »
Dream Chaser Prepares for Flight
Posted on June 19, 2015 at 2:42 pm by commercial-crew-program.

Sierra Nevada Corporation’s Dream Chaser engineering test article is being prepped for its second free-flight test at NASA’s Armstrong Flight Research Center in California later this year. The flight test is a milestone under NASA’s Commercial Crew Integrated Capability (CCiCap) agreement with SNC.  The wings, windows and landing gear are installed. The Dream Chaser’s the nose skid will have thermal protection system tiles on the vehicle, manufactured at Kennedy Space Center’s Thermal Protection System Facility, for the flight test. The performance of the tiles will be assessed following the touch down on the runway.

SNC will share their thermal protection system work and a status of the Dream Chaser spacecraft to media and social media attending CRS-7 activities at Kennedy Space Center next week.

https://blogs.nasa.gov/commercialcrew/2015/06/19/dream-chaser-prepares-for-flight

Offline AnalogMan

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Re: SNC Dream Chaser UPDATE Thread
« Reply #570 on: 06/27/2015 11:44 am »
Tile Shop Prepping Heat Shields for Future Flights
Steven Siceloff, KSC June 26, 2015

Heat shield tiles are getting stronger to make the next generation of American spacecraft safer as they experience searing heat and plasma on their way back into Earth’s atmosphere for landing.

[…]

Jacobs Technology engineers are producing test samples that will be used to protect the Dream Chaser spacecraft under development by Sierra Nevada Corporation (SNC) in partnership with the agency’s Commercial Crew Program. The facility is the same workshop that produced space shuttle heat shield tiles at NASA’s Kennedy Space Center for more than 30 years.

SNC continues to advance its development of the reusable Dream Chaser spacecraft that launches vertically atop a United Launch Alliance Atlas V rocket and returns to Earth for a runway landing. Like the shuttle, the Dream Chaser will use several kinds of protective materials on the outside of the spacecraft to form a protective barrier. Tiles made from improved silica-based blocks will make up most of the belly and upper portion of the heat shield, while a new material developed at NASA’s Ames Research Center called “TUFROC” will cover the nose and leading edges. Those are the surfaces that must resist and mitigate the highest temperatures the spacecraft experiences from the friction of re-entering Earth’s atmosphere. Another factor that makes the tiles desirable for a heat shield: they are mostly air. As a result, the tiles are extremely lightweight, a vital factor for spacecraft design in which weight is the primary driver of launch costs.

At first glance, the white blocks with a Styrofoam texture look no different than the thousands of blocks made for the space shuttle heat shields before being coated with a black ceramic material. But these new blocks incorporate advanced materials, making them stronger while maintaining the capability to prevent searing plasma from jeopardizing a spacecraft or its crew during the hazardous phase of a mission as the crew returns from orbit through Earth’s atmosphere on the way to a landing.

The nose skid of the Dream Chaser currently is outfitted with thermal protection system tiles to assess performance in preparation for a free-flight test of the spacecraft at the agency’s Armstrong Flight Research Center targeted for later this year.

https://blogs.nasa.gov/commercialcrew/2015/06/26/tile-shop-prepping-heat-shields-for-future-flights/

Offline rdale

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Re: SNC Dream Chaser UPDATE Thread
« Reply #571 on: 07/28/2015 06:09 pm »
Stephen Clark @StephenClark1
NASA's Phil Mcallister says Sierra Nevada’s next Dream Chaser drop test in California hopefully by the end of the year.

1:55pm · 28 Jul 2015 · TweetDeck

Offline Chris Bergin

Re: SNC Dream Chaser UPDATE Thread
« Reply #572 on: 09/10/2015 04:38 pm »
Presser:

Sierra Nevada Corporation Announces New
Dream Chaser® Spacecraft – Designated Landing Site Program

SPARKS, Nev. (September 10, 2015) – Sierra Nevada Corporation’s (SNC) Space Systems announces the launch of a new program, the Dream Chaser®-Preferred Landing Site Program, in which SNC will work with spaceports and commercial airports to become a designated landing site for the Dream Chaser spacecraft.

“The number of applicants requesting spaceport licenses both domestically and internationally has increased dramatically over the past 24 months,” said John Roth, vice president of business development and strategy for SNC’s Space Systems. “SNC’s Dream Chaser spacecraft is the only commercial space vehicle that is capable not only of a runway landing, but landing on runways that already support commercial aircraft. SNC has created this program based on the tremendous interest we have received to date from spaceports and airports around the world that want to host Dream Chaser landings as a stimulant to their local economies.”

Through the Dream Chaser-Preferred Landing Site Program, SNC is offering three different levels of designation, with the highest level culminating in the Federal Aviation Administration (FAA) issuing a re-entry license to SNC for the designated spaceport or airport.  This program was created based on similar work currently being done with Ellington Spaceport in Houston, Texas and the Huntsville International Airport Authority (HIA) in Huntsville, Alabama.

Recently, the FAA granted a launch site license to the Houston Airport System (HAS), allowing the launch of reusable vehicles from Houston.  HAS was only the tenth location to be granted such a license. SNC has worked with HAS for over a year to aid in the submittal of their license and to assess the feasibility of landing Dream Chaser in Houston, home of NASA’s Johnson Space Center.

As announced in June at the Paris Air Show, SNC is also working with the City of Huntsville to assess the feasibility of landing the Dream Chaser spacecraft at the Huntsville International Airport, a public-use airport. Huntsville plays a significant role in the national and global space community.

“Dream Chaser is poised to lead the commercial space industry in reusable, low-Earth orbital flight,” said Mark N. Sirangelo, corporate vice president of SNC’s Space Systems. “The benefits of multiple landing sites would be significant to both the landing site community and to the Dream Chaser network of domestic and international partners. With each Preferred Landing Site designation, comes a greater opportunity to make commercial space an accessible reality.”

SNC’s Dream Chaser spacecraft requires only a 10,000 feet or longer runway and does not have any onboard toxic consumables, including propellants. Therefore, the vehicle has very limited environmental impact and affords immediate post-landing access to the spacecraft.

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Offline llanitedave

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Re: SNC Dream Chaser UPDATE Thread
« Reply #573 on: 09/11/2015 05:05 am »
Great that they can land.  Now if we can only find a way to get them to take off!
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Offline Phyto

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Re: SNC Dream Chaser UPDATE Thread
« Reply #574 on: 09/11/2015 04:58 pm »
Great that they can land.  Now if we can only find a way to get them to take off!

Unfortunately this eagle has charlie-horses in its talons & can't get off the limb its perched on.
Good luck soon!  ;) ;D

Offline Phyto

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Re: SNC Dream Chaser UPDATE Thread
« Reply #575 on: 09/11/2015 05:06 pm »
Off Topic: Just bumped up against the 120 second Rule: Very good rule! Won't happen again.

Offline Chris Bergin

Re: SNC Dream Chaser UPDATE Thread
« Reply #576 on: 10/06/2015 05:34 pm »
Just because we've not reported on here for a while, and SNC promoted their CRS2 ambitions via congratulating ULA on the 100th launch....

http://www.nasaspaceflight.com/2015/10/dream-chaser-fighting-her-place-space/

I think we need to keep this in the Commercial Crew section for now.
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Offline Chris Bergin

Re: SNC Dream Chaser UPDATE Thread
« Reply #577 on: 10/07/2015 08:46 pm »
Great news!

Sierra Nevada Corporation’s Dream Chaser® Program Preparing for
Second Free-Flight Test and First Orbital Test

SPARKS, Nev. (October 7, 2015) – In anticipation of a second phase of flight testing, Sierra Nevada Corporation’s (SNC) Space Systems has announced significant updates to two Dream Chaser®  spacecraft currently in development. The spacecraft are the atmospheric engineering test article (ETA) and the advanced composite orbital vehicle, which when tested will undergo a suborbital and orbital flight regimen, respectively. SNC’s Mark Sirangelo provided a program update at the International Symposium for Commercial and Personal Spaceflight (ISPCS) in New Mexico.

“The SNC team is readying the ETA in order to begin the second phase of atmospheric flight testing early next year and our strategic partner, Lockheed Martin, is leveraging best practices in tooling and composites to manufacture the first orbital Dream Chaser spacecraft,” said Mark. N. Sirangelo, corporate vice president, SNC’s Space Systems. “Both efforts have been ongoing simultaneously and we are very pleased with the progress to date.”

Since flight test phase one, in which SNC’s Dream Chaser ETA successfully returned trajectory data of the flight profile, SNC has made significant structural and systems improvements to the ETA including the composite wings and aeroshells. SNC also invested heavily in maturing the spacecraft orbital avionics, guidance navigation and control, the flight software, and employed a number of new processes, all of which will be used on the orbital vehicle as well. Finally, the advanced orbital Thermal Protection System (TPS), announced in June, was installed on the ETA skid in order to do advanced testing of the actual orbital TPS in this important area.

“The Dream Chaser ETA is currently scheduled to arrive at Armstrong Flight Research Center in early 2016 in order to begin the second phase of atmospheric flight test.”

In parallel to the ETA upgrade, SNC has made significant progress on the build of the first Dream Chaser orbital vehicle manufactured by Lockheed Martin. Lockheed Martin is leveraging best-practices in composite manufacturing from the Skunk Works®, its advanced development programs division, as well as its extensive experience in manufacturing and assembly from the F-35 Lightning II.

Lockheed Martin recently completed the Dream Chaser orbital cabin assembly, marking a significant milestone in the construction of this vehicle.  This assembly is the largest high-temperature unitized structure ever fabricated at U.S. Air Force Plant 4. The assembly utilized three-dimensional woven joints, to integrate internal frames with external carbon skins in a single co-bond operation, meaning nearly all fasteners on this critical cabin assembly are eliminated. This state-of –the-art approach to design and manufacturing is a highly efficient and affordable design solution.

“Upon completion, the Dream Chaser orbital vehicle will be the most advanced composite structure ever built. We look forward to Dream Chaser becoming the world leader in this area and to its first orbital flight,” said Sirangelo.

SNC’s Dream Chaser spacecraft is the only reusable, lifting-body, multi-mission-capable vehicle with a commercial runway landing capability - anywhere in the world. The Dream Chaser is a safe, affordable, flexible and reliable system capable of crewed and uncrewed transportation services to low-Earth orbit destinations such as the International Space Station. SNC has designed the Dream Chaser Cargo System as a solution for NASA’s commercial transportation services needs under the Cargo Resupply Services 2 contract and for other fully autonomous orbital missions.

###

Photo Cutline: SNC technicians inspect the Dream Chaser ETA.

About Sierra Nevada Corporation’s Space Systems
Sierra Nevada Corporation’s Space Systems business area based in Louisville, Colorado, designs and manufactures advanced spacecraft, space vehicles, rocket motors and spacecraft subsystems and components for the U.S. Government, commercial customers, as well as for the international market.  SNC’s Space Systems has more than 25 years of space heritage and has participated in over 400 successful space missions through the delivery of over 4,000 systems, subsystems and components.  During its history, SNC’s Space Systems has concluded over 70 programs for NASA and over 50 other clients. For more information about SNC’s Space Systems visit www.sncspace.com and follow us at Facebook.com/SNCSpaceSystems and Twitter @SNCspacesystems.
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Offline adrianwyard

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Re: SNC Dream Chaser UPDATE Thread
« Reply #578 on: 10/07/2015 10:14 pm »
Great news!

Sierra Nevada Corporation’s Dream Chaser® Program Preparing for
Second Free-Flight Test and First Orbital Test

SPARKS, Nev. (October 7, 2015) – In anticipation of a second phase of flight testing, Sierra Nevada Corporation’s (SNC) Space Systems has announced significant updates to two Dream Chaser®  spacecraft currently in development. The spacecraft are the atmospheric engineering test article (ETA) and the advanced composite orbital vehicle, which when tested will undergo a suborbital and orbital flight regimen, respectively. SNC’s Mark Sirangelo provided a program update at the International Symposium for Commercial and Personal Spaceflight (ISPCS) in New Mexico.

“The SNC team is readying the ETA in order to begin the second phase of atmospheric flight testing early next year and our strategic partner, Lockheed Martin, is leveraging best practices in tooling and composites to manufacture the first orbital Dream Chaser spacecraft,” said Mark. N. Sirangelo, corporate vice president, SNC’s Space Systems. “Both efforts have been ongoing simultaneously and we are very pleased with the progress to date.”

Since flight test phase one, in which SNC’s Dream Chaser ETA successfully returned trajectory data of the flight profile, SNC has made significant structural and systems improvements to the ETA including the composite wings and aeroshells. SNC also invested heavily in maturing the spacecraft orbital avionics, guidance navigation and control, the flight software, and employed a number of new processes, all of which will be used on the orbital vehicle as well. Finally, the advanced orbital Thermal Protection System (TPS), announced in June, was installed on the ETA skid in order to do advanced testing of the actual orbital TPS in this important area.

“The Dream Chaser ETA is currently scheduled to arrive at Armstrong Flight Research Center in early 2016 in order to begin the second phase of atmospheric flight test.”

In parallel to the ETA upgrade, SNC has made significant progress on the build of the first Dream Chaser orbital vehicle manufactured by Lockheed Martin. Lockheed Martin is leveraging best-practices in composite manufacturing from the Skunk Works®, its advanced development programs division, as well as its extensive experience in manufacturing and assembly from the F-35 Lightning II.

Lockheed Martin recently completed the Dream Chaser orbital cabin assembly, marking a significant milestone in the construction of this vehicle.  This assembly is the largest high-temperature unitized structure ever fabricated at U.S. Air Force Plant 4. The assembly utilized three-dimensional woven joints, to integrate internal frames with external carbon skins in a single co-bond operation, meaning nearly all fasteners on this critical cabin assembly are eliminated. This state-of –the-art approach to design and manufacturing is a highly efficient and affordable design solution.

“Upon completion, the Dream Chaser orbital vehicle will be the most advanced composite structure ever built. We look forward to Dream Chaser becoming the world leader in this area and to its first orbital flight,” said Sirangelo.

SNC’s Dream Chaser spacecraft is the only reusable, lifting-body, multi-mission-capable vehicle with a commercial runway landing capability - anywhere in the world. The Dream Chaser is a safe, affordable, flexible and reliable system capable of crewed and uncrewed transportation services to low-Earth orbit destinations such as the International Space Station. SNC has designed the Dream Chaser Cargo System as a solution for NASA’s commercial transportation services needs under the Cargo Resupply Services 2 contract and for other fully autonomous orbital missions.

###

Photo Cutline: SNC technicians inspect the Dream Chaser ETA.

About Sierra Nevada Corporation’s Space Systems
Sierra Nevada Corporation’s Space Systems business area based in Louisville, Colorado, designs and manufactures advanced spacecraft, space vehicles, rocket motors and spacecraft subsystems and components for the U.S. Government, commercial customers, as well as for the international market.  SNC’s Space Systems has more than 25 years of space heritage and has participated in over 400 successful space missions through the delivery of over 4,000 systems, subsystems and components.  During its history, SNC’s Space Systems has concluded over 70 programs for NASA and over 50 other clients. For more information about SNC’s Space Systems visit www.sncspace.com and follow us at Facebook.com/SNCSpaceSystems and Twitter @SNCspacesystems.

...and here's the image from the press release: http://www.sncspace.com/AboutUs/NewsDetails/1923

Offline Chris Bergin

Re: SNC Dream Chaser UPDATE Thread
« Reply #579 on: 10/07/2015 11:38 pm »
Orbital Dream Chaser!!

SNC:

Lockheed Martin recently completed our Dream Chaser® orbital cabin assembly!
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