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#1 2017-03-07 19:03:05

Oldfart1939
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Registered: 2016-11-26
Posts: 691

Blue Origin Press Release

Blue Origin today announced the first customer, Eutelsat, for it's New Glenn Rocket satellite operations beginning in 2021. Photos of the first BE-4 rocket motor were also released for public viewing.

http://spaceflight101.com/wp-content/up … 7x1024.jpg

The announced payload capacity to LEO is 45 metric tons, with a 13 metric ton payload to GTO.

Last edited by Oldfart1939 (2017-03-07 19:04:03)

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#2 2017-03-07 19:11:26

RobS
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From: South Bend, IN
Registered: 2002-01-15
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Re: Blue Origin Press Release

That's going to be a good sized rocket! Also, in response to Musk's announcement that he'd fly two tourists around the moon in 2018, the Washington Post published an article about a leaked document Blue Origin provided the Trump Administration proposing a cargo lander able to take 10,000 lbs to the moon by the early 2020s. It's beginning to look likely that people will return to the moon some time in the next decade. If nothing else, someone needs to develop a simple lunar lander capable of being launched to orbit by a Falcon Heavy and propelled to the moon by a stage lifted to orbit by another Falcon Heavy. Two of them can put 106 tonnes into LEO, not that much less than a Saturn V, and with our improved technology the result should be just about as good, though it'll be MUCH cheaper.

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#3 2017-03-07 19:33:30

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 9,851

Re: Blue Origin Press Release

Saw the news release but only the assumption of packages to the moon in another being sent by that rocket.
The engine was in the carrier for assembly in the image which was in one of the articles.
http://spaceflight101.com/blue-origin-s … -customer/

I did post the sizing image which did the comparison in another topic for the falcon all the way to the saturn size launch vehicles...

The seven-meter diameter reusable first stage hosting seven BE-4 engines, each with a thrust of 2,450 Kilonewtons and burning Liquefied Natural Gas and Liquid Oxygen. The rocket’s second stage will be powered by a vacuum-optimized version of the BE-4.

Simular to the design methods for the Space x Falcon for engine use and reuse of the first stage. I also like the lower engine count.

United Launch Alliance’s future Vulcan rocket. Although ULA is keeping its options open, BE-4 has been identified as the primary candidate for Vulcan with Aerojet Rocketdyne’s AR-1 considered a fallback plan in case BE-4 runs into major problems.

Another nice part of this is that its got a paying customer for building its own rocket as well as being a supply chain for its engine to another company.

GTO and Beyond Earth Orbit would be handled by a 95-meter tall version sporting a cryogenic third stage powered by a version of Blue’s BE-3 that is already flying on the New Shepard.

Also another plus as that engine will be considered a man rated stage engine...

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#4 2017-03-07 21:19:31

Oldfart1939
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Registered: 2016-11-26
Posts: 691

Re: Blue Origin Press Release

SpaceNut-

The BE-3 is a hydrolox system, and has it's own problems/limitations, being cryogenic.

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#5 2017-03-07 21:34:38

SpaceNut
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Re: Blue Origin Press Release

That just means we are duration of use limited for distance such as lunar play ground only....we need another fuel for longer durations and distances from earth.

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#6 2017-03-07 21:56:30

Oldfart1939
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Posts: 691

Re: Blue Origin Press Release

I personally have no issues with either methylox or hypergolic combinations involving N2H3CH3 and NTO. The hydrazines can be a mixture, which subsequently lowers the melting (freezing) point. This has an excellent Isp = 325s. Musk talks about the new Raptor engine using CH4/LOX with Isp = 383 +/-. Granted, that's SpaceX, not Blue Origin.

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#7 2017-03-07 22:30:34

GW Johnson
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From: McGregor, Texas USA
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Re: Blue Origin Press Release

One of the problems with life support is getting rid of waste heat.  One place to dump it is in your storable propellant tanks,  to keep your propellants warm.  There may not be all that much,  but there is some. 

It's a lot easier if your propellant tank has a layer of insulation on its outside with an outer sun-reflective surface.  That keeps the sunlit side from overheating,  while the shadowed side doesn't lose heat as fast.  That way the little bit of waste heat you dump into the tank becomes quite effective.   

Hydrazine FP = 34.7 F,  BP = 236.3 F
UDMH   FP = -71.0 F   BP = 146 F
MMH   FP = -62.3 F   BP = 189.5 F
50-50 hydrazine UDMH   FP = 18.8 F   BP = 158 F

So,  actually,  I think MMH is the better storable deal than the hydrazine-UDMH blend.  That's likely why Spacex prefers MMH for its Draco/Super Draco thrusters.  It's the oxidizer that is the real storable limit:

NTO  FP = 11.8 F   BP = 70.1 F  which is a pretty severe limitation,  about as bad as plain hydrazine.     

IRFNA   FP = -63.4 F  BP = 150 F is a lot better,  but you lose quite a bit of Isp:  IRFNA-UDMH 320 s vac versus 336 for NTO-UDMH.  It is hypergolic,  though,  and even hypergolic with kerosene.  RP-1 kerosene lists as FP = -76 F,  with 10% evap-as-BP = 390 F.  IRFNA-RP-1 Isp lists as 309 s vac. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#8 2017-03-08 09:11:11

Oldfart1939
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Re: Blue Origin Press Release

The FP of RP-1 may be -76 F, but it undergoes a massive increase in viscosity prior to freezing, rendering it incapable of flow. The Falcon 9 uses RP-1 chilled to -7 C because of this undesirable feature. In Diesels, it's called "gelling."

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#9 2017-03-10 03:54:00

Quaoar
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Posts: 345

Re: Blue Origin Press Release

SpaceNut wrote:

That just means we are duration of use limited for distance such as lunar play ground only....we need another fuel for longer durations and distances from earth.

I think that if we want to expand in space we have to learn how to handle LH2: there are many studies about zero boil-off active cooling systems: we only have to build, test and optimize them, instead of renouncing to LH2 for long travels. For Mars CH4 may be a good option  for in ISRU, but if we want to go farther at a point we have to turn to nuclear and LH2 is the only propellant that really works with NTR.

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#10 2017-03-10 17:20:08

SpaceNut
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Re: Blue Origin Press Release

Risk aversion but Nasa has been working on this a bit...

Long Term ZBO(Zero-boil-off) Liquid Hydrogen Storage Tanks

Cryogenic Propellant Storage & Transfer (CPST)Technology Demonstration Mission (TDM)

OVERVIEW OF HYDROGEN STORAGE TECHNOLOGIES

For the NTR I think that the heavier the atomic weight that is liquid will give the biggest level of force when energized by the thermal heat of the reactor but I think we are a bit off topic with the NTR discusion.

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#11 2017-03-20 06:43:51

Quaoar
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Re: Blue Origin Press Release

SpaceNut wrote:

For the NTR I think that the heavier the atomic weight that is liquid will give the biggest level of force when energized by the thermal heat of the reactor but I think we are a bit off topic with the NTR discusion.

Bigger molecular weight gives higher thrust but lower specific impulse, as I know.

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#12 2017-03-20 08:25:02

Oldfart1939
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Re: Blue Origin Press Release

Exhaust velocity is inversely proportional to the molecular weight of the exhaust gas, which is also true for Isp.

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#13 2017-03-20 09:43:51

GW Johnson
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From: McGregor, Texas USA
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Posts: 2,459
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Re: Blue Origin Press Release

Molecular weight as a determinant of exhaust velocity gets "cloudy" when you consider solids,  which depending upon how metallized,  are actually significantly two-phase,  not straight gas flows.  This shows up in smaller specific heat ratio as well as average stream molecular weight.  Solids have the reputation of higher thrust,  too.

I rather think the higher thrust is merely the inherently higher frontal thrust density of the solid over a liquid system.  The solid's exhaust plane area is a higher fraction of stage frontal area than any liquid designs I have ever seen,  and so also is the throat plane area.  That's just more thrust for the same stage frontal area,  and by considerable margin.  Which is why SRB's are so popular to get overloaded liquid launch rockets off the pad.  They stage off earlier:  that's the lower Isp. 

The two-phase "dirty" gas is also why you do not want multiple O-rings in your segment and closure joints,  and why you never,  ever obstruct the joints in the case insulation that lead to these O-rings.  NASA killed a crew violating those design rules with its shuttle SRB's,  and they never learned the lesson.  Most of the upstream O-rings were found cut during disassembly. 

With a single O-ring in the joints,  you leak check by pressurizing the entire motor,  which drives the O-ring to the side of its groove right where you want it.  You need not leak check at full motor pressure.  If it holds at 5 psi,  it'll hold at 5000 psi,  in properly designed ring and groove geometry.  That's something you verify early in case hydro-burst testing,  before you ever fire a live motor. 

NASA obstructs its insulation joints with RTV or similar "pooky",  which causes the motor gases to wormhole-through and strike the O-ring at a single point,  instead of gently pressurizing over the whole ring length.  Concentrated loads are always far more destructive at breaking materials of any kind. 

This gets compounded by NASA's insistence on leak-checking the joints at full motor pressure by pressurizing between the rings.  This always drives the upstream ring to wrong side of its groove.  The motor ignition pressurization transient must then slam it back to the correct side of the groove before it will seal at all. 

The third thing NASA has never understood about all this solid design stuff is the two-phase nature of the motor "gases",  and the tremendous damage they can do if not handled correctly.  As the "gas" wormholes through the "pooky" they insist on using,  the dominant gaseous component can cool some by expansion and by convection to the solid materials,  but the solids in the stream do neither.  Whatever is in the way of that wormhole stream gets hit by a supersonic sandblast of 5000-6000 F grit.  Which neatly explains the circular-shape cuts in the upstream O-rings found upon disassembly. 

You combine the wormhole-induced cut to the upstream O-ring with the concentrated point load effect of the wormhole stream striking the downstream O-ring,  and there's enormous potential for failure.  Embrittle the O-ring by cold-soaking it,  and that is why it snapped and killed Challenger's crew.  Some crud randomly clogged the leaking joint for almost 73 seconds,  before turbulence shook it loose,  thus letting the leak stream cut the SRB retention strut.  If that hadn't happened,  the joint would have soon parted with multi-million-pound PA kick loads.  Either way,  the bird was doomed. 

Adding a third O-ring to the joint design (which is what they did) merely adds another cascading stage to this wormhole process.  That is why I say that NASA never fixed the design problem,  except to make it worse.  They never flew cold again,  which (combined with some luck) is really why they never had another Challenger-type accident. 

Thiokol knew better,  but built exactly what NASA demanded,  so as not to lose the contract.  The astonishingly arrogant ignorance of NASA in this is actually rather typical of government labs.  The evidence to support that statement is:  nearly all of them farm out development work to contractors,  very little new design testing is attempted by the lab. 

GW

Last edited by GW Johnson (2017-03-20 10:16:44)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#14 2017-03-20 17:59:14

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 9,851

Re: Blue Origin Press Release

Thanks for the confirmation Oldfart1939 about molecular weight and exhaust isp or velocity. The NTR is just a souped up version of the ion drive in how it functions.

I agree GW Johnson that metals are not a good thing here on earth but that may be the case when we do not have the better choices to make from once we are not where the typical materials of oxygen and Hydrogen resides.

As for solids for earth use properly designed so as to not fail are just fine for the brute force needed at launch.

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#15 2017-03-20 22:23:17

Oldfart1939
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Registered: 2016-11-26
Posts: 691

Re: Blue Origin Press Release

The problem with GW's "dirty gas," is it's really no longer a gas and isn't calculable by the gas equations based on the "perfect gas laws." Which--it ain't. This is where theory fades and empiricism prevails. Another perfect example of how "theory guides---but experiment decides."

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#16 2017-03-21 21:48:13

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 9,851

Re: Blue Origin Press Release

This is what I have heard for the F1 engine creation and used on the Saturn rockets from GW in that 1 part science 2 part craftmanship art....

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#17 2017-04-02 15:38:31

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 2,459
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Re: Blue Origin Press Release

My version of that saying is:

"Rocket science ain't just science,  it's 50% art,  only 40% science,  and it's 10% blind dumb luck". 

The art is the part never written down,  because no manager ever wanted to pay for that.  It got passed on one-on-one from older guy to younger guy,  on the job,  until about 1980-ish,  when big business began to discard en masse everybody over 40 or 45 as "too expensive",  in the very mistaken belief that all engineers were the same.  They did this because younger ones worked cheaper.  If you ever wondered why we cannot seem to do what we once did before 1980,  that's really why.  About half the knowledge is lost as the years tick on,  because there is no one there to pass it on. 

The science part is that which was actually written down,  usually only because of contract requirements.  Management's usual (but very mistaken) belief is that such documents (1) cover everything that is necessary to know (they don't),  and (2) are written in "cookbook format" so that a high school dropout could build the thing for slave labor wages (they are not written that way). 

I know this is true,  I did engineering management myself,  but I knew better than to do it "their" way.  And so I was VERY successful at it.  The R&D I managed at what was supposed to be a bunch of hicks working in a production-only facility,  made the corporate research center look like the bunch of incompetent fools that they really were.  Top corporate management hated me.  My troops and colleagues loved me.  Just one thing out of hundreds for an example:  we invented 3 ways for a HARM rocket motor to pass the slow cookoff fuel fire test (long considered impossible),  and tested 1 full scale very successfully.  Our plant got closed (because of corporate politics abetted by bad government policy) before we could get the technology to USN. 

The blind dumb luck part is just inherent.  Murphy's Law.

Two caveats:  (1) those percentages apply only to routine production work;  the luck and art factors are higher (!!!) in development work,  and (2) it applies to all of engineering,  not just rocketry. 

GW

PS:  the plant where I worked made the little solid "ullage" motors used on the Saturns (1 and 5).  That was before I went to work there,  but I was familiar with the Saturns,  just because I was a space enthusiast.  These were little solid motors about the size and shape and mass of a very small flower pot,  which in 3's provided just enough acceleration so that the propellants gathered quite effectively about the suction point in a matter of only 10's of seconds.  That simple idea enabled reliable restart of liquid engines in space.  2 starts:  use 6.  3 starts,  use 9.  Etc.

Last edited by GW Johnson (2017-04-02 15:51:09)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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