XCOR and the Lynx rocket

[QuantumG]

How many of us feel about LOX/LH2 is how most of us felt about turbopumps before SpaceX came along.

Now the amateur community is doing turbopumps.. so who knows what the future will bring.

[jongoff]

I actually heard about this (from a source other than Jeff Greason) the same day I chatted with Jeff, but it looks like XCOR has now hot-fire tested their 2500lbf LOX/LH2 subscale engine:

http://www.xcor.com/press/2013/13-11-19_XCOR_ULA_announce_hydrogen_milestone.html

************

Hot Fire: XCOR Aerospace and United Launch Alliance Achieve Major Propulsion Milestone in Liquid Hydrogen Engine Program

Nov. 19, 2013, Mojave, CA and Centennial, CO - XCOR Aerospace and United Launch Alliance (ULA) announced a significant milestone today, the first successful hot fire of the subscale 2500 lbf thrust XR-5H25 engine in the XCOR and ULA liquid hydrogen (LH2) engine development program.

“The first hot fire of any engine is a major milestone but the first firing of a liquid hydrogen engine in our LH2 program is an even bigger accomplishment,” noted XCOR Chief Executive Officer Jeff Greason. “The hot fire of this engine moves us forward on a path to routine tests and further demonstration of fully reusable, high reliability rocket engines for which we are known.”

“XCOR’s ability to develop inexpensive, innovative and out-of-the-box solutions to some of the most challenging problems in modern cryogenic rocket engine technology was on display in Mojave,” said George Sowers, vice president of Strategic Architecture at ULA. “It was a great first set of engine runs and we look forward to seeing the engine and XCOR’s unique piston pumps integrated together in 2014.”

Conceived as a lower-cost, risk-managed approach, the goal of the XCOR/ULA LH2 engine program is to produce and operate a subscale demonstration engine.   This demonstrator will enable a future decision to pursue development of a flight-ready cryogenic upper-stage engine in the 25,000 lbf thrust class.  This technology has significant growth potential due to its unique thermodynamic cycle and piston pump. The larger thrust XCOR XR-8H21 LH2 engine should cost significantly less to produce and be much easier to operate than competing upper stage rocket engine technologies.

XCOR Chief Operating Officer Andrew Nelson said “I was very impressed with how our team dedicated itself to achieving a task that has not been accomplished in at least a quarter century, maybe more; the development of a new way to do liquid hydrogen rocket engines that fundamentally breaks current cost, reliability and operational models.  Even more than that, it will be the first piston-pump-fed LH2 rocket engine anywhere.”

The 5H25 engine is intended as a testbed, but could also be suitable for future in-space use on upper stages, earth departure stages, landers, and probes. Nelson added, “This is a significant leap forward in the hope to deliver yet another line of innovation and business to XCOR. And it is only taking place right here.”

#  #  #

About XCOR Aerospace:  XCOR Aerospace is based in Mojave, California.  It is currently starting the process to create a new Research and Development Center in Midland, Texas and an operational and manufacturing site at the Kennedy Space Center in Florida. XCOR® builds safe, reliable and reusable rocket-powered vehicles, propulsion systems, advanced non-flammable composites and rocket piston pumps. XCOR works with aerospace prime contractors and government customers on major propulsion systems, while also building Lynx®.  Lynx is a piloted, two-seat, fully reusable liquid rocket-powered vehicle that takes-off and lands horizontally. The Lynx-family of vehicles serves three primary missions depending on their specific type including: research & scientific missions, private spaceflight, and micro satellite launch (only on the Lynx Mark III). Lynx production models (designated Lynx Mark II) are designed to be robust, multi-mission (research / scientific or private spaceflight) commercial vehicles capable of flying to 100+ km in altitude up to four times per day. Lynx vehicles are available to customers in the free world on a wet lease basis to start their own manned space flight program. (www.xcor.com).

United Launch Alliance: ULA is a 50-50 joint venture owned by Lockheed Martin and The Boeing Company, and is the nation’s rocket company, bringing together two of the launch industry’s most experienced and successful teams – Atlas and Delta. ULA provides reliable, cost-efficient space launch services for the Department of Defense, NASA, the National Reconnaissance Office and other commercial organizations. ULA program management, engineering, test, and mission support functions are headquartered in Denver, Colo.  Manufacturing, assembly and integration operations are located at Decatur, Ala., and Harlingen, Texas. Launch operations are located at Cape Canaveral AFS, Fla., and Vandenberg AFB, Calif. For more information on ULA, visit the ULA Web site at www.ulalaunch.com, or call the ULA Launch Hotline at 1-877-ULA-4321 (852-4321). Join the conversation at www.facebook.com/ulalaunch and twitter.com/ulalaunch.

************

My commentary:

I hope that when they're done integrating the pumps, and doing all the testing and tweaking for this 2500lbf subscale engine, that they wrap it into a fully-integrated flightweight engine. A good T/W, high Isp, 2500lbf, LOX/LH2 engine could be pretty interesting for a wide range of upper stage and in-space applications. Particularly small lunar landers, and propulsion for first-generation *fully* reusable orbital launch vehicles.

~Jon

[jongoff]

Oh, I forgot my other comment: W00t! Congrats guys! This was awesome!

~Jon

[baldusi]

Four of those on the  moon could have a T/W of 1 with a vehicle of 27tonnes of mass. Incidentally, that's a fully loaded Centaur plus 6tonnes. Congrats to XCOR.

[go4mars]

Very exciting to see this milestone!  Good comment Jon, a commercial off the shelf would be great for many applications.  I hope XCOR has the contractual freedom to offer that!

[billh]

Excellent!

Why isn't the exhaust blue?

[sublimemarsupial]

Excellent!

Why isn't the exhaust blue?

Was wondering that too. It looks much more like the RS-68 exhaust, which is redish due to the ablative nozzle, than the SSME, which is purely regenerative.

[guckyfan]

Excellent!

Why isn't the exhaust blue?

Was wondering that too. It looks much more like the RS-68 exhaust, which is redish due to the ablative nozzle, than the SSME, which is purely regenerative.

I had wondered the same. Maybe that's it. For an early test it may well be an ablative nozzle.

[jongoff]

Excellent!

Why isn't the exhaust blue?

Was wondering that too. It looks much more like the RS-68 exhaust, which is redish due to the ablative nozzle, than the SSME, which is purely regenerative.

I had wondered the same. Maybe that's it. For an early test it may well be an ablative nozzle.

No, XCOR never uses ablative nozzles AFAIK. I'm not sure why the color, but it could be impurities in the LH2 or something. I'll ask.

~Jon

[jongoff]

I got busy and forgot to post this, but I asked Doug Jones about the yellow flame, and this is what he said:

We found photos of ESA Vulcain engines that run red-orange, and the emission spectrum of hydrogen has lines at 656, 486, 434, and 410 nm. (Balmer 3,4,5,6 according to Wiki.) The blend seems to give a mostly orange hue. Compare to a Vulcain plume:

http://www.dlr.de/dlr/en/desktopdefault.aspx/tabid-10259/315_read-218/#gallery/1286

Next run I'm going to set up a mirror so I can get a mark one eyeball view of the plume. I doubt if I'll get a sunburn from a short exposure to the UV.

[Garrett]

I got busy and forgot to post this, but I asked Doug Jones about the yellow flame, and this is what he said:

We found photos of ESA Vulcain engines that run red-orange, and the emission spectrum of hydrogen has lines at 656, 486, 434, and 410 nm. (Balmer 3,4,5,6 according to Wiki.) The blend seems to give a mostly orange hue. Compare to a Vulcain plume:

http://www.dlr.de/dlr/en/desktopdefault.aspx/tabid-10259/315_read-218/#gallery/1286

Next run I'm going to set up a mirror so I can get a mark one eyeball view of the plume. I doubt if I'll get a sunburn from a short exposure to the UV.

The UV exposure shouldn't be too dangerous, but he should wear a pair of clear safety glasses just in case. The extra millimeter or two of plastic should reduce the UV exposure to his eyes quite a lot, without reducing the visible light view. Or he could set up a very thick plexiglass window in between him and the mirror.

Richard Feynman famously looked directly at a nuclear explosion during the Manhattan project by viewing it through a car window.

[deltaV]

So why aren't SSME and RL-10 exhausts orange too? A difference in exhaust temperature perhaps?

[Nomadd]

 I would expect them to start out fuel rich and work their way up, if only to keep temps down in the early tests.

[Step55]

I would expect them to start out fuel rich and work their way up, if only to keep temps down in the early tests.

Agree

Couple of random photos of H2/LOX engines firing during development.

[john smith 19]

Oh, I forgot my other comment: W00t! Congrats guys! This was awesome!

Very impressive. 

Have they mentioned if the full scale unit would be single chamber or a cluster of these units?

I'm also curious if you they lose much Isp due to a combustion cycle, rather than tapping the main chamber cooling jacket for pump drive like the RL10.

[jongoff]

Oh, I forgot my other comment: W00t! Congrats guys! This was awesome!

Very impressive. 

Have they mentioned if the full scale unit would be single chamber or a cluster of these units?

Definitely one bigger chamber for the 25klbf class unit. It turns out their 7500lbf LOX/Methane engine they did was about the right size (for a 25klbf LOX/LH2 system) if you ran it with LOX/LH2 at the full chamber pressure of a pump-fed system.

I'm also curious if you they lose much Isp due to a combustion cycle, rather than tapping the main chamber cooling jacket for pump drive like the RL10.

Who ever said they were running this gas-generator cycle? They've got their own patent-pending variant on expander cycle that should give similar Isp performance.

~Jon

[russianhalo117]

I actually heard about this (from a source other than Jeff Greason) the same day I chatted with Jeff, but it looks like XCOR has now hot-fire tested their 2500lbf LOX/LH2 subscale engine:

http://www.xcor.com/press/2013/13-11-19_XCOR_ULA_announce_hydrogen_milestone.html

************

Hot Fire: XCOR Aerospace and United Launch Alliance Achieve Major Propulsion Milestone in Liquid Hydrogen Engine Program

Nov. 19, 2013, Mojave, CA and Centennial, CO - XCOR Aerospace and United Launch Alliance (ULA) announced a significant milestone today, the first successful hot fire of the subscale 2500 lbf thrust XR-5H25 engine in the XCOR and ULA liquid hydrogen (LH2) engine development program.

“The first hot fire of any engine is a major milestone but the first firing of a liquid hydrogen engine in our LH2 program is an even bigger accomplishment,” noted XCOR Chief Executive Officer Jeff Greason. “The hot fire of this engine moves us forward on a path to routine tests and further demonstration of fully reusable, high reliability rocket engines for which we are known.”

“XCOR’s ability to develop inexpensive, innovative and out-of-the-box solutions to some of the most challenging problems in modern cryogenic rocket engine technology was on display in Mojave,” said George Sowers, vice president of Strategic Architecture at ULA. “It was a great first set of engine runs and we look forward to seeing the engine and XCOR’s unique piston pumps integrated together in 2014.”

Conceived as a lower-cost, risk-managed approach, the goal of the XCOR/ULA LH2 engine program is to produce and operate a subscale demonstration engine.   This demonstrator will enable a future decision to pursue development of a flight-ready cryogenic upper-stage engine in the 25,000 lbf thrust class.  This technology has significant growth potential due to its unique thermodynamic cycle and piston pump. The larger thrust XCOR XR-8H21 LH2 engine should cost significantly less to produce and be much easier to operate than competing upper stage rocket engine technologies.

XCOR Chief Operating Officer Andrew Nelson said “I was very impressed with how our team dedicated itself to achieving a task that has not been accomplished in at least a quarter century, maybe more; the development of a new way to do liquid hydrogen rocket engines that fundamentally breaks current cost, reliability and operational models.  Even more than that, it will be the first piston-pump-fed LH2 rocket engine anywhere.”

The 5H25 engine is intended as a testbed, but could also be suitable for future in-space use on upper stages, earth departure stages, landers, and probes. Nelson added, “This is a significant leap forward in the hope to deliver yet another line of innovation and business to XCOR. And it is only taking place right here.”

#  #  #

About XCOR Aerospace:  XCOR Aerospace is based in Mojave, California.  It is currently starting the process to create a new Research and Development Center in Midland, Texas and an operational and manufacturing site at the Kennedy Space Center in Florida. XCOR® builds safe, reliable and reusable rocket-powered vehicles, propulsion systems, advanced non-flammable composites and rocket piston pumps. XCOR works with aerospace prime contractors and government customers on major propulsion systems, while also building Lynx®.  Lynx is a piloted, two-seat, fully reusable liquid rocket-powered vehicle that takes-off and lands horizontally. The Lynx-family of vehicles serves three primary missions depending on their specific type including: research & scientific missions, private spaceflight, and micro satellite launch (only on the Lynx Mark III). Lynx production models (designated Lynx Mark II) are designed to be robust, multi-mission (research / scientific or private spaceflight) commercial vehicles capable of flying to 100+ km in altitude up to four times per day. Lynx vehicles are available to customers in the free world on a wet lease basis to start their own manned space flight program. (www.xcor.com).

United Launch Alliance: ULA is a 50-50 joint venture owned by Lockheed Martin and The Boeing Company, and is the nation’s rocket company, bringing together two of the launch industry’s most experienced and successful teams – Atlas and Delta. ULA provides reliable, cost-efficient space launch services for the Department of Defense, NASA, the National Reconnaissance Office and other commercial organizations. ULA program management, engineering, test, and mission support functions are headquartered in Denver, Colo.  Manufacturing, assembly and integration operations are located at Decatur, Ala., and Harlingen, Texas. Launch operations are located at Cape Canaveral AFS, Fla., and Vandenberg AFB, Calif. For more information on ULA, visit the ULA Web site at www.ulalaunch.com, or call the ULA Launch Hotline at 1-877-ULA-4321 (852-4321). Join the conversation at www.facebook.com/ulalaunch and twitter.com/ulalaunch.

************

My commentary:

I hope that when they're done integrating the pumps, and doing all the testing and tweaking for this 2500lbf subscale engine, that they wrap it into a fully-integrated flightweight engine. A good T/W, high Isp, 2500lbf, LOX/LH2 engine could be pretty interesting for a wide range of upper stage and in-space applications. Particularly small lunar landers, and propulsion for first-generation *fully* reusable orbital launch vehicles.

~Jon

AND here is the equivalent ULA link: http://www.ulalaunch.com/site/pages/News.shtml#/159/

[john smith 19]

Definitely one bigger chamber for the 25klbf class unit. It turns out their 7500lbf LOX/Methane engine they did was about the right size (for a 25klbf LOX/LH2 system) if you ran it with LOX/LH2 at the full chamber pressure of a pump-fed system.

Handy.  . That sounds like they can lower the development risk and schedule quite a bit, provided the the shift in mixture ratio and injectors does not cause any trouble.   

Who ever said they were running this gas-generator cycle? They've got their own patent-pending variant on expander cycle that should give similar Isp performance.

Oops.  Demonstrating once again that's what's happens when you "assume."

All the stuff I've seen from John Whiteheads group at LLNL relied on hypergolic ignition or catalytic breakdown. I guess I'd assumed if the cycle was transferable between propellants it'd had also had to be combustion (or catalytic breakdown) based. 

But if it's an expander variant that would be the first wholly new expander engine since the late 50's.    , so nearer 50 than 25 years.

And of course running an LO2/LH2 engine with an expander variant driven piston pump makes them unique.

[ edit In early papers Whitehead's team described their simulation process and estimated that at about 5000 lb thrust it would be more efficient to move to turbo pumps, however I think they were based on a catalytic or GG source of drive gas for the pump. Going to 25000lb suggests the expander variant changes everything  ]

That's just huge. 

[baldusi]

But if it's an expander variant that would be the first wholly new expander engine since the late 50's.    , so nearer 50 than 25 years.

Vinci and RD-0146 might beg to differ.

[john smith 19]

But if it's an expander variant that would be the first wholly new expander engine since the late 50's.    , so nearer 50 than 25 years.

Vinci and RD-0146 might beg to differ.

I should have qualified that by "In the US" OT but has RD-0146 flown yet either?