Dream Chaser for CEV requirement

[Flyaway]

A view of the Dream Chaser 100 and 200, the latter being the crewed version.

https://twitter.com/x/status/1611432910438993930

View: https://twitter.com/sierraspaceco/status/1611432910438993930

 

[Rhinocrates]

Exciting. I assume that it's an accurate representation. I've altered the contrast and noticed that the vertical fins appear to have no rudders. I know it's a render, but I think that if they detailed the tiles, they'd detail a hinge. They are mounted on flat portions of the body, so they could pivot (once it's on approach to landing of course).

Obviously no cockpit windows, so either a completely automated landing and/or synthetic vision.

Somewhat resembles the Lockheed X-33 (not VentureStar), but the wings are larger and have LERXs and the top of the body is convex, not flat. You can see that the curve peaks over where the docking tunnel meets the back plane - it's only the wide angle distortion that makes it look like it has a trapezoidal cross-section. The DC-100 series looks the way it does because it's a direct descendent of the HL-20/X-38 and used aero data from those programmes to save development costs. This indicates that they've done extensive independent research and development, meaning a serious commitment of resources.

 

[martinbayer]

Exciting. I assume that it's an accurate representation. I've altered the contrast and noticed that the vertical fins appear to have no rudders. I know it's a render, but I think that if they detailed the tiles, they'd detail a hinge. They are mounted on flat portions of the body, so they could pivot (once it's on approach to landing of course).

Obviously no cockpit windows, so either a completely automated landing and/or synthetic vision.

Somewhat resembles the Lockheed X-33 (not VentureStar), but the wings are larger and have LERXs and the top of the body is convex, not flat. You can see that the curve peaks over where the docking tunnel meets the back plane - it's only the wide angle distortion that makes it look like it has a trapezoidal cross-section. The DC-100 series looks the way it does because it's a direct descendent of the HL-20/X-38 and used aero data from those programmes to save development costs. This indicates that they've done extensive independent research and development, meaning a serious commitment of resources.

View attachment 690653

Other than scale, what are any notable and relevant *qualitative* differences between the final Lockheed X-33 and VentureStar designs to you?

 

[Rhinocrates]

Principally the placement of the vertical stabilizers. By its final iteration, the VentureStar had also moved to using an external cargo module which would apparently be discarded before re-entry.

 

[Rhinocrates]

The penultimate iteration, by the way.

 

[martinbayer]

My best guess is that the LM design team in the end desperately, singlemindedly focused on just trying to make the X-33 flying slice of pie in the sky work instead of also updating the SSTO design accordingly, but your points are very well taken. For any interested parties, I wholeheartedly recommend though to perform a quantitative comparison of launch and dry masses vs. fuselage volume as well as overall wetted and aerodynamic surface areas for the competing VTHL SSTO RLV LM "lifting body" and Rockwell Space Shuttle Orbiter based/derived classical wing/body configuration designs - and that doesn't even include design factors like the complexity of non-circular fuselages ...

 

[Rhinocrates]

My best guess is that the LM design team in the end desperately, singlemindedly focused on just trying to make the X-33 flying slice of pie in the sky work instead of also updating the SSTO design accordingly,

Yeah, and by the end, VentureStar looked like a pretty good first stage of a 2STO system... though if stage separation was going to happen outside the atmosphere but at less than orbital velocity, they could have saved a lot of weight on the thermal protection.

As for Sierra's DC-200, assuming it's too wide to be enclosed in a shroud even with folding wings, its shaped to generate lift - so are they going to stick it on the top of a booster and thereby impose huge lateral forces at the top end during launch, or are they going to side-mount it? As Scott has pointed out, it makes little economic sense if the booster is expendable and you don't recover the main engines, but if you have a reusable booster system like Falcon, it's another story. Can you side-mount on a modified Falcon/Falcon Heavy? Would Starship make it irrelevant?

Would they be better off prioritising Orbital Reef instead of DC-200 and cede the launch to LEO market to Spacex in the medium term? https://www.cbsnews.com/news/blue-origin-sierra-space-orbital-reef-space-station-plans/

I wonder what will emerge.

 

[NMaude]

As for Sierra's DC-200, assuming it's too wide to be enclosed in a shroud even with folding wings

I suspect that the Vulcan-Centaur's payload faring will be able to encapsulate the DC-200 with its' wings folded as the rocket is 18Ft in diameter.

A new video has been posted by TheSpaceBucket giving its current status:

Spaceplanes offer quite a few unique benefits if done correctly, While the Space Shuttle was by no means perfect, it helped create and launch a host of space infrastructure still in use today. This being said, spacecraft reusability is a complex process with more to consider than just getting the spacecraft back in one piece. A process that Sierra Space has been working on for decades.

Right now Sierra Space is completing some of the final preparations for the first launch of Dream Chaser Tenacity. Recent updates from the company highlight that the test article is on track to launch later this year for the first time. This comes in addition to a sneak peek released yesterday of a new dream chaser variant and design.

While the specific future of this spaceplane is unknown, we do know some of the goals that Sierra Space is working toward. Currently, the first goal is to successfully create and demonstrate the capabilities of an uncrewed Dream Chaser variant with launches to the International Space Station. Here I will go more in-depth into Dream Chaser Tenacity’s progress, the new dream chaser variant, what to expect in the future, and more.

In the comments section there was this interesting comment considering the different proposed variants:

NOV4​

2 hours ago
DC-200 is the crewed variant. They've talked about the designations at CES last year. DC-100 is cargo, 200 is crew and 300 is for national security. This was confirmed by one of the employees working on the vehicles on twitter. The crewed vehicle will likely not have any traditional front facing windows to reduce risk.

 

[TomS]

As for Sierra's DC-200, assuming it's too wide to be enclosed in a shroud even with folding wings

I suspect that the Vulcan-Centaur's payload faring will be able to encapsulate the DC-200 with its' wings folded as the rocket is 18Ft in diameter.

A new video has been posted by TheSpaceBucket giving its current status:

In the comments section there was this interesting comment considering the different proposed variants:

NOV4​

2 hours ago
DC-200 is the crewed variant. They've talked about the designations at CES last year. DC-100 is cargo, 200 is crew and 300 is for national security. This was confirmed by one of the employees working on the vehicles on twitter. The crewed vehicle will likely not have any traditional front facing windows to reduce risk.

A crewed version can't go inside a fairing, for abort and escape reasons.

 

[NMaude]

A crewed version can't go inside a fairing, for abort and escape reasons.

True, I was thinking of the cargo variants. As for a manned version Sierra Space has no doubt already done significant wind-tunnel testing of the Dream Chaser mounted on both the Atlas Centaur 5 and Vulcan Centaur with no payload faring.

 

[sferrin]

A crewed version can't go inside a fairing, for abort and escape reasons.

True, I was thinking of the cargo variants. As for a manned version Sierra Space has no doubt already done significant wind-tunnel testing of the Dream Chaser mounted on both the Atlas Centaur 5 and Vulcan Centaur with no payload faring.

NASA - NASA's Marshall Center Completes Wind Tunnel Testing for Sierra Nevada Corporation's Dream Chaser® Space System

NASA's Marshall Space Flight Center successfully completed wind tunnel testing of the Dream Chaser® Space System for Sierra Nevada Corp. (SNC) Space Systems.

www.nasa.gov

 

[martinbayer]

My best guess is that the LM design team in the end desperately, singlemindedly focused on just trying to make the X-33 flying slice of pie in the sky work instead of also updating the SSTO design accordingly,

Yeah, and by the end, VentureStar looked like a pretty good first stage of a 2STO system... though if stage separation was going to happen outside the atmosphere but at less than orbital velocity, they could have saved a lot of weight on the thermal protection.

In my honest opinion, even for a rocket propelled TSTO RLV booster, from an overall concept optimization point of view a classical wing/body design with a circular cylindrical fuselage would still be the superior, if perhaps visually/aesthetically slightly less exciting, alternative. There are some parallels here between RLVs and subsonic airliners, where fairly regularly more or less unorthodox alternative lifting body/flying wing designs are being pitched, but never adopted by any actual commercial airframe maker who knows their real economics and associated risks.

 

[publiusr]

Rockwell got the short end of the stick.

Principally the placement of the vertical stabilizers. By its final iteration, the VentureStar had also moved to using an external cargo module which would apparently be discarded before re-entry.

Mini-Polyus style. Now, that could allow for very wide payloads…had Venture Star been any good :/

 

[martinbayer]

Rockwell got the short end of the stick.

Principally the placement of the vertical stabilizers. By its final iteration, the VentureStar had also moved to using an external cargo module which would apparently be discarded before re-entry.

Mini-Polyus style. Now, that could allow for very wide payloads…had Venture Star been any good :/

I honestly have no idea what your "Mini-Polyus" reference is intended to imply regarding aerodynamics, but if you mean to indicate that the Rockwell X-33 wing body design was the most straightforward and promising design approach, based on actual Shuttle design experience, and got shafted by NASA in favor of the fancy shmancy shifting body LM design (and not that I'm bitter or anything), I completely concur with you.

 

[Flyaway]

Dream Chaser - The Dream Of Lifting Body Space Planes:

View: https://youtu.be/LK0XZjQf7AM

 

[NMaude]

Another excellent video from Scott Manley.

 

[Flyaway]

Another image of the DC-201 but with windows!

https://twitter.com/x/status/1614029691907620867

View: https://twitter.com/systems_zero/status/1614029691907620867

 

[NCQ]

Another image of the DC-201 but with windows!

https://twitter.com/x/status/1614029691907620867

View: https://twitter.com/systems_zero/status/1614029691907620867

The original picture (plus another of DC-200) are from this Aviation Week article:

In Pictures: Inside Sierra Space’s Dream Chaser Factory | Aviation Week Network

Sierra Space has set its sights on development of a space ecosystem in low Earth orbit, the first element of which is the Dream Chaser spaceplane.

aviationweek.com

It also has some short quotes about DC-200:

Sierra expects to decide later this year or in early 2024 whether it will need to add a third DC-100-series Dream Chaser or instead transition directly to production of the larger DC-200 optionally crewed follow-on version. Tenacity, along with the cargo module, will shortly be shipped to NASA’s Neil Armstrong Test Facility (formerly Plum Brook Station) in Ohio for thermal testing.

Differentiated from the DC-100 series by a 40% increase in size, upper-body windows and fixed wings, the redesigned DC-200 is expected to be flight-tested without a crew in late 2025—and with astronauts onboard in 2026. Although design details are yet to be finalized, the DC-200 is likely to be configured with lower body-mounted wings and twin canted tails, similar to the Boeing X-37, and will feature a simpler outer mold line without the pronounced upper-body hump of the baseline version.

 

[TomcatViP]

Reasonably thinking, the odds for the latter, larger, design to get contracted by NASA are as void as space itself.
If something using the same design philosophy was to be produced, Boeing would only have to roll out larger versions of the X-37B.

Boeing has a much larger experience in winged re-entry and a design already finalized and proven.

 

[NMaude]

Boeing has a much larger experience in wing re-entry and a design already finalized and proven.

Boeing at the moment has its hands full trying to debug and successfully test the CST-100 before it can think of moving onto such projects.

 

[publiusr]

Either way BOR-Next remains unmanned…sigh.

I guess I’ll just have to hammer this flatter:

Dream Chaser Plush Toy

We’re making our Dream Chaser® spaceplane a little more comfortable for cuddling with this Dream Chaser plush toy. Any child (by age or spirit) would love snuggling up with this soft spacecraft.

store.sncorp.com

 

[Flyaway]

In Pictures: Inside Sierra Space’s Dream Chaser Factory Guy Norris January 10, 2023

In Pictures: Inside Sierra Space’s Dream Chaser Factory | Aviation Week Network

Sierra Space has set its sights on development of a space ecosystem in low Earth orbit, the first element of which is the Dream Chaser spaceplane.

aviationweek.com

 

[NMaude]

Here's this interesting new video by TheSpaceBucket comparing the Space Shuttle's and Dream Chaser's heat-shields and whether or not the Dream Chaser's heat-shield design is superior:

When reentering the Earth’s atmosphere, different spacecraft typically experience temperatures around 3000 degrees Fahrenheit or 1650 degrees Celcius. This immense heat along with other forces make this part of the mission by far one of the most complex and dangerous. Decades ago the Space Shuttle changed how we accessed space by implementing a large spaceplane that could be reused.

One of the core pieces in this process was its heat shield which consisted of tens of thousands of individual and specific tiles. Unfortunately, this method was far from perfect and caused multiple problems including significant safety concerns along with time delays. Focusing on today’s technology, Sierra Space is working on a next-generation spaceplane named Dream Chaser which is scheduled to launch for the first time later this year.

While Dream Chaser has different goals and constraints, the two spaceplanes share a lot of similarities. This includes a heat shield with thousands of individual tiles that Sierra Space is confident is a significant improvement from the past Shuttle design. Here I will go more in-depth into the problem with the Space Shuttles’ thermal protection, how exactly Dream Chaser compares, why this is important for the future, and more.

 

[sferrin]

Boeing has a much larger experience in wing re-entry and a design already finalized and proven.

Boeing at the moment has its hands full trying to debug and successfully test the CST-100 before it can think of moving onto such projects.

To be charitable.

 

[NMaude]

TheSpaceBucket has put out a new Dream Chaser video concerning its upcoming launch and future propulsion:

Dream Chaser is scheduled to lift off for the first time in the third quarter of this year. This long-awaited mission will be the first test of a handful of different systems. This includes the heat shield, rocket body, thrusters, and main propulsion, just to name a few. All of which will be put to the test with a mission profile that takes Dream Chaser Tenacity to the International Space Station and back for a runway landing.

One of the most important yet often overlooked components of Dream Chaser is its two main engines on the rear of the spacecraft. While unlike the Space Shuttle, these won’t be used during liftoff, they will help Dream Chaser get into its operational orbit depending on the mission profile. It’s important to point out however that the Vortex Engine has yet to be flown in space.

Originally, on-orbit propulsion of the Dream Chaser was proposed to be provided by twin hybrid rocket engines capable of repeated starts and throttling. This was before an acquisition by the company all the way back in 2014. Here I will go more in-depth into the primary Dream Chaser propulsion system, what this looks like on Tenacity, what to expect in the coming months, and more.

 

[NMaude]

Another update on the status of the Dreamchaser from TheSpaceBucket:

Dream Chaser is a spaceplane trying to change how we access space. Decades ago, the Space Shuttle reinvented the spacecraft design and what was possible within the industry. While by no means perfect, it helped both build and support a lot of key space infrastructure still in use today. Dream Chaser while very different, has ambitious goals for the near future.

In terms of progress, right now Dream Chaser Teancity, the first Dream Chaser test article meant for space, is preparing for its mission. The mission begins with Tenacity being launched on top of United Launch Alliance’s Vulcan Centaur where it will then dock to the ISS before returning safely for a gentle runway landing. However, with a lot of work still left from both companies, it brings up the question of whether or not the third quarter of this year is still a realistic launch date.

Dream Chaser’s past has been plagued with quite a few delays. For over a decade now the spaceplane has been going through various development, testing, and now final preparation. Here I will go more in-depth into the possibilities of new delays, Tenacity’s progress, ULA and Sierra Space’s plans, and more.

Full article here - https://thespacebucket.com/is-dream-c...

 

[Flyaway]

It’s likely to be shunted off of Vulcan’s second launch due to how much it is delayed.

 

[Moose]

Nah let's do it right: tandem launch a pair of them on SLS Block II.

 

[NMaude]

Another update to do with the Dream Chaser:

Dream Chaser is a next-generation spacecraft under development by Sierra Space trying to change how we access space. The spaceplane features a modern design and multiple variants depending on the mission at hand. While not nearly as big as the Space Shuttle was, it still offers some unique capabilities and an impressive cargo capacity.

With its first ever mission scheduled to happen in the third quarter of this year, a lot of that technology and design will be put to the test. Here Dream Chaser Tenacity will attempt to launch atop ULA’s Vulcan before docking with the ISS and eventually returning to Earth for a runway landing. This launch will be with the cargo variant of Dream Chaser, however, there also is a crewed and upgraded cargo version as well.

Not to mention the addition of the Shooting Star service module which not only increases payload capacity but also offers extra services. After over a decade of development, manufacturing, and testing, we are closer than ever to an actual launch attempt. Here I will go more in-depth into the three variants of Dream Chaser and their designs, the upcoming mission with Tenacity, and more.

I look forward to its' launch and I hope there are no hiccups with the first launch of the Vulcan-Centaur so that there are no delays.

 

[FighterJock]

Another update to do with the Dream Chaser:

Dream Chaser is a next-generation spacecraft under development by Sierra Space trying to change how we access space. The spaceplane features a modern design and multiple variants depending on the mission at hand. While not nearly as big as the Space Shuttle was, it still offers some unique capabilities and an impressive cargo capacity.

With its first ever mission scheduled to happen in the third quarter of this year, a lot of that technology and design will be put to the test. Here Dream Chaser Tenacity will attempt to launch atop ULA’s Vulcan before docking with the ISS and eventually returning to Earth for a runway landing. This launch will be with the cargo variant of Dream Chaser, however, there also is a crewed and upgraded cargo version as well.

Not to mention the addition of the Shooting Star service module which not only increases payload capacity but also offers extra services. After over a decade of development, manufacturing, and testing, we are closer than ever to an actual launch attempt. Here I will go more in-depth into the three variants of Dream Chaser and their designs, the upcoming mission with Tenacity, and more.

I look forward to its' launch and I hope there are no hiccups with the first launch of the Vulcan-Centaur so that there are no delays.

Same here NMaude, I want to see the Dream Chaser succeed as well. Let's see if Vulcan-centaur can succeed as well without anymore delays to the launch schedule.

 

[publiusr]

Here's this interesting new video by TheSpaceBucket comparing the Space Shuttle's and Dream Chaser's heat-shields and whether or not the Dream Chaser's heat-shield design is superior:

This website got me to thinking:

Flying Brickyard Postponed: A 1972-1973 Study of an Interim Ablative Space Shuttle Heat Shield

The story of spaceflight told through missions and programs that did not happen - that is, the great majority of them.

spaceflighthistory.blogspot.com

The link above talks about snap-on panels of ablatives.

But what if panels could have tiles attached to them…perhaps in a firmer way?

So the only individual tiles that have to be adhered are to cover tool access ports—with those also like the shuttle wheel well panels?

That might cut down on the tesselation headaches—especially with simpler designs like Starship—whose closest analog is this:

MTKVP: Glushko’s Opening Gambit

What it was: A fairly sophisticated 1973-76 attempt to square the circle between the ballistic capsules favoured by Russian spacecraft designers and the Space Shuttle analog being demanded of them …

falsesteps.wordpress.com

On Brazen Wings - From the Pseudo Space Race to Independence and Beyond.

On Brazen Wings Prologue It was an awfully cold, near frigid Tuesday morning in 1986 when Thomas Paine found himself checking in to a motel, just outside Rockledge, Florida. Normally he would stay closer to the Cape, but tourists in town for the launch were still packing the nearer...

www.alternatehistory.com

That might allow larger but simpler panels.

 

[FighterJock]

Let’s wait until first flight of the Dream Chaser publiusr, I for one want the new heat shield to be better than the Shuttle‘s after all it has been over forty years since the Shuttle’s heat shield was designed and built.

 

[TomcatViP]

@publiusr : remember that thermal expansion is a fraction of the overall length. A shorter part dilates less than a longer one. Hence interstices b/w smaller tiles don't have to be large and edge to edge stress is lower (less ripples).

 

[publiusr]

The tiles would be small-but several on large panels. I was thinking the backs of the panels of corregation with tiles tied through holes.

 

[Flyaway]

I am going to speculate that Dreamchaser won’t launch this year based on stuff I’ve seen about the delays.

 

[Flyaway]

Almost right as it’s maiden launch is now NET December 2023. Also that Vulcan’s maiden launch is likely to be in the summer now not May.

Dream Chaser is delayed again, raising questions about Vulcan launch plans

Is there still a path to Vulcan flying a national security mission in 2023?

arstechnica.com

 

[NMaude]

Although the below video was posted six-days ago (I've only just stumbled across it) here's an update for the Dreamchaser's status:

 

[NMaude]

TheSpaceBucket has just put out this video about the Dream Chaser's expendable Shooting Star module (A rather apt name):

After many years of development and testing, Dream Chaser’s first launch is scheduled to happen only months from now. As Sierra Space prepares, they are not only working on Dream Chaser Tenacity but also its Shooting Star transport vehicle. An equally important piece of equipment that changes what this spaceplane is capable of.

Shooting star is an extended module that attaches to the back of Dream Chaser. On a lot of future missions including the CRS flights with NASA, we can expect to see this hardware included. Some of its features include extra payload capacity, disposal services, power generation, and space, just to name a few. Unlike Dream Chaser, Shooting Star is meant to burn up in the atmosphere when its mission is complete.

This is why Sierra Space is working hard to innovate and create a capable design that can keep up with the future demand of Dream Chaser. For years now the company has been testing its materials and other important factors to try and create the most viable and effective hardware. Here I will go more in-depth into Shooting Star’s design, its importance for future Dream Chaser missions, what to expect in the coming months, and more.

Full article here - https://thespacebucket.com/why-dream-...

 

[NMaude]

Oh, for fucks sake:

Dream Chaser is a next-generation spaceplane that has been under development for over a decade. Its first official test article named Tenacity has recently been going through some final construction and testing in preparation for the maiden flight which was scheduled to happen only months from now around August. Unfortunately, a few things just went wrong that will push this launch back quite a bit.

Specifically, earlier this week NASA updated its internal schedule to show that Sierra Space’s Dream Chaser spacecraft will now berth to the International Space Station no earlier than December 17, 2023. For a while now it was known that Sierra Space was targeting the third quarter of this year or right around August for this mission.

Just to make matters worse, Vulcan which is already a decent bit behind schedule, is now running into anomalies prior to its first flight. This is a big deal because Dream Chaser will use this rocket as its ride to the ISS. Here I will go more in-depth into the recent delay, problems with ULA’s Vulcan, what to expect in the coming months, and more.

For more space-related content check out - https://thespacebucket.com/

 

[djfawcett]

Hi guys,

OFF TOPIC

I have an eleven year old grandson that loves reading this forum. His father is an AF Academy grad and currently at the pentagon. I imagine my grandson will follow suit. But, and this is the issue, profanity usually lends nothing to a discussion. If mom or grandma sees the profanity in this forum, that will be it for my grandson, and that would be a shame. So......please refrain from profanity if at all possible. Thank you much, Dave