NOFBX monoprop system?

[ugordan]

I've been listening to Max Vozoff's interview on the Space Show and he mentioned this thing he was involved with. A non-toxic monopropellant system which aims to replace hydrazine in virtually all space applications and it's supposed to have Isp comparable to biprops - 320 to 340 s.

This is supposed to be the (currently minimalistic) site of the joint venture offering it: Innovative Space Propulsion

There's some more info here http://www.firestar-engineering.com/NOFB-MP.html
A pretty informative Feb 2011 AIAA presentation: http://www.aiaa.org/pdf/industry/presentations/Greg_Mungas.pdf

Supposedly they're working with 4 CCDev teams looking at requirements for retrofitting this NOFBX sytem as their spaceceraft's propulsion.

Anyone know more about this? Easy to handle, non toxic, high performing - sounds too good to be true.

[deltaV]

They do not appear to have released enough technical info (e.g. what exactly their propellant is) for outsiders to evaluate their claims.

[yg1968]

In the interview, Max Vozoff said that this system would be tested at the ISS in 2012.

[ugordan]

Well, one of the Space Station Project Control Board notes from February (posted on L2) has this bit:

Working with OZ to verify NOFBX schedule

Hard to tell with all the acronyms floating around, but could be related to that ISS 2012 demo.

[yinzer]

Their patent filings suggest that they're mixing N20 with 2C hydrocarbons: ethane, ethylene, and acetylene.

[deltaV]

Their patent filings suggest that they're mixing N20 with 2C hydrocarbons: ethane, ethylene, and acetylene.

I would be inclined to call that a "premixed bipropellant" rather than a "monopropellant". I certainly see why their marketing department prefers the latter terminology.

[Proponent]

What's the order of magnitude of the cost and other operational benefits of eliminating hydrazine?

[mlorrey]

Their patent filings suggest that they're mixing N20 with 2C hydrocarbons: ethane, ethylene, and acetylene.

I would be inclined to call that a "premixed bipropellant" rather than a "monopropellant". I certainly see why their marketing department prefers the latter terminology.

A better question is: Is that a stable mixture?

[Robotbeat]

Their patent filings suggest that they're mixing N20 with 2C hydrocarbons: ethane, ethylene, and acetylene.

I would be inclined to call that a "premixed bipropellant" rather than a "monopropellant". I certainly see why their marketing department prefers the latter terminology.

Same thing, in my book.

And just about any monopropellant can become explosive.

[Proponent]

Page 6 of the Greg Mungas's presentation classifies hybrids and NOFBX systems as having "low acoustics" and other systems as not.  I can see why solids, liquids and hybrids might intrinsically have different acoustic properties, but why should the acoustics of NOFBX, for example, differ fundamentally from that of monoprop hypergols, for example?

[ugordan]

A better question is: Is that a stable mixture?

One of the videos shows a container being dropped from 12 m height.

[rklaehn]

A better question is: Is that a stable mixture?

One of the videos shows a container being dropped from 12 m height.

That proves nothing. N2O for example is very stable. It is hard to get any reaction out of it. But it can detonate given the wrong circumstances.

A better test would be to put different sized blasting caps into it and see how big a blasting cap you need to set it off. But such tests would inevitably end with a giant crater once you use a big enough blasting cap, so they would not make for a good PR movie.

[ugordan]

That proves nothing. N2O for example is very stable. It is hard to get any reaction out of it.

It proves it will not detonate if you give it the wrong look.

But it can detonate given the wrong circumstances.

All propellants can. Even TNT as a high explosive is much safer to handle than say nitroglycerin.

[HMXHMX]

That proves nothing. N2O for example is very stable. It is hard to get any reaction out of it.

It proves it will not detonate if you give it the wrong look.

But it can detonate given the wrong circumstances.

All propellants can. Even TNT as a high explosive is much safer to handle than say nitroglycerin.

Only mixed propellants or natural monopropellants.  LOX can't detonate, neither can methane, propane, RP-1, etc.

[Danderman]

Only mixed propellants or natural monopropellants.  LOX can't detonate, neither can methane, propane, RP-1, etc.

Since LOX is a propellant but not a fuel.

[yinzer]

Only mixed propellants or natural monopropellants.  LOX can't detonate, neither can methane, propane, RP-1, etc.

Since LOX is a propellant but not a fuel.

What does this mean, exactly?  LOX won't detonate (it's an oxidizer), nor will RP-1 (it's a fuel).  Both are usually considered propellants.

[A_M_Swallow]

Only mixed propellants or natural monopropellants.  LOX can't detonate, neither can methane, propane, RP-1, etc.

Since LOX is a propellant but not a fuel.

What does this mean, exactly?  LOX won't detonate (it's an oxidizer), nor will RP-1 (it's a fuel).  Both are usually considered propellants.

They are talking about monopropellants - single substance that will power a rocket.  LOX is half of many bipropellants.

[HMXHMX]

Only mixed propellants or natural monopropellants.  LOX can't detonate, neither can methane, propane, RP-1, etc.

Since LOX is a propellant but not a fuel.

What does this mean, exactly?  LOX won't detonate (it's an oxidizer), nor will RP-1 (it's a fuel).  Both are usually considered propellants.

They are talking about monopropellants - single substance that will power a rocket.  LOX is half of many bipropellants.

I was responding to a post that claimed "...all propellants can" detonate, not just monopropellants.  Pedantic to be sure, but nonetheless I was trying to be precise.

[A_M_Swallow]

We are getting off topic.

If you want LOX to explode boil it in a sealed container.

[kkattula]

We are getting off topic.

If you want LOX to explode boil it in a sealed container.

That would be a BLEVE, a type of explosion, but not the same as detonation.

Some mixed mono-props are quite stable. Armadillo worked extensively with 50% H202 mixed with (IIRC) 8% methanol. No problems.

Try it with 80%+ H202. Big problems. Big kaboom quite likely.

[mlorrey]

Only mixed propellants or natural monopropellants.  LOX can't detonate, neither can methane, propane, RP-1, etc.

Since LOX is a propellant but not a fuel.

....

There are military veterans out there who have learned (some the hard way) that LOX is quite capable of "detonation" when dropped on a newly polished combat boot, or when LOX on the ground is stepped on with a boot that has grease/oil on its sole.

"detonation" is a function of both oxidizer and fuel, as well as the conditions under which both are ignited together (pressure, in particular). For instance, you can use C-4 like sterno to cook canned food, and it is perfectly safe to do so, but detonating it with a detonator will get an entirely different combustion reaction out of it....

[kkattula]

Only mixed propellants or natural monopropellants.  LOX can't detonate, neither can methane, propane, RP-1, etc.

Since LOX is a propellant but not a fuel.

....

There are military veterans out there who have learned (some the hard way) that LOX is quite capable of "detonation" when dropped on a newly polished combat boot, or when LOX on the ground is stepped on with a boot that has grease/oil on its sole.

"detonation" is a function of both oxidizer and fuel, as well as the conditions under which both are ignited together (pressure, in particular). For instance, you can use C-4 like sterno to cook canned food, and it is perfectly safe to do so, but detonating it with a detonator will get an entirely different combustion reaction out of it....

LOX soaked into asphalt is also really bad news.

But all those involve addition of a fuel. You can't make LOX in a clean tank detonate.

[simonbp]

A pretty informative Feb 2011 AIAA presentation: http://www.aiaa.org/pdf/industry/presentations/Greg_Mungas.pdf

Wow, that's really neat presentation. An Isp of 320 sec is getting into the LOX/CH4 range, but with much, much less hassle. I especially love the truncated aerospike ascent vehicle; it's a brilliant idea I've never seen suggested before.

WRT to storage safety, they say they're about to start going for MIL-STD2105C, which is the standard specification for non-nuclear munitions. Doesn't mean it will be super-safe, but not more dangerous than your average solid rocket.

This actually seems like an ideal propellant for a depot. It's high enough Isp to useful, apparently storable over a wide range, and allows you to consolidate the depot down to a single fluid...

[Patchouli]

That proves nothing. N2O for example is very stable. It is hard to get any reaction out of it.

It proves it will not detonate if you give it the wrong look.

But it can detonate given the wrong circumstances.

All propellants can. Even TNT as a high explosive is much safer to handle than say nitroglycerin.

C4 is even safer you can shoot it, throw it in a fire or even put it in a microwave oven and it will not explode.

[mlorrey]

Interesting presentation.

Questions: Why such low thrust levels? What are the limitations on building an SSTO vehicle with a single tank, a few engines, etc? Are there limits on how much you can pressurize this propellant and/or on running it through a turbopump?

[aftercolumbia]

One of the gnarliest propellants for going off on its own is N2H4.  I've read lots of warnings about it, but have yet to hear of a fatal accident involving the stuff, despite the fact that it is used on almost every launch vehicle and satellite.  Even some exceptions, like the Shuttle, use MMH, which can also go off on its own, even though I've never heard of it being used as a monopropellant.  I don't think UDMH can go off on its own.  C2H4 can theoretically go off on its own, since it has a positive enthalpy, but I have no idea how or if that can be done.

The most famous propellant for going off on its own that we've discussed so far is H2O2, which, I think, gets it's bad rap only because it went off on its own under the undisciplined circumstances of the 1940s and 1950s.  There is an Armadillo video where they pour it on a leather show and watch it deflagrate in dramatic fashion (I thought it was funny, especially since I've read of it blowing up Bell X-1 prototypes with leather in their seals way back in the 1940s.)  H2O2 is actually quite easy to control, and, I think, much safer than LOX in the circumstances I've just described.  H2O2 of course, has the disadvantage that a little bit of the wrong stuff will set off your whole tank, whereas with LOX, a little bit of the wrong stuff will only have a local effect.  This was true in Apollo 13, which unfortunately, turned out to have waaaaayyyy too much of the wrong stuff in one of her tanks.

[mlorrey]

One of the gnarliest propellants for going off on its own is N2H4.  I've read lots of warnings about it, but have yet to hear of a fatal accident involving the stuff, despite the fact that it is used on almost every launch vehicle and satellite.  Even some exceptions, like the Shuttle, use MMH, which can also go off on its own, even though I've never heard of it being used as a monopropellant.  I don't think UDMH can go off on its own.  C2H4 can theoretically go off on its own, since it has a positive enthalpy, but I have no idea how or if that can be done.

The most famous propellant for going off on its own that we've discussed so far is H2O2, which, I think, gets it's bad rap only because it went off on its own under the undisciplined circumstances of the 1940s and 1950s.  There is an Armadillo video where they pour it on a leather show and watch it deflagrate in dramatic fashion (I thought it was funny, especially since I've read of it blowing up Bell X-1 prototypes with leather in their seals way back in the 1940s.)  H2O2 is actually quite easy to control, and, I think, much safer than LOX in the circumstances I've just described.  H2O2 of course, has the disadvantage that a little bit of the wrong stuff will set off your whole tank, whereas with LOX, a little bit of the wrong stuff will only have a local effect.  This was true in Apollo 13, which unfortunately, turned out to have waaaaayyyy too much of the wrong stuff in one of her tanks.

True, but keeping a clean tank these days isn't hard. Anybody with flightline experience handling LOX safely can handle H2O2 safely. It isn't a substance you want to be pouring into a tank in the open air, and propellant tanks always get a pretty complete scrubbing at the factory.

[jabe]

interesting application about  NOFBX in this artcle about Mojave.

For a contract with the Defense Advanced Research Projects Agency, Firestar developed a NOFBX-fueled piston engine for high-altitude, long-endurance drones. “It’s the unmanned equivalent of the U-2 spyplane,” Mungas says. Piston engines, powering everything from generators to small aircraft, have been modified in-house to run at altitudes with almost no oxygen.

Curious to see where the uses of NOFBX eventually lead to .
jb

[kevin-rf]

How big of a problem will shifting CG be in a first stage?

With bi-Prop first stages you often place the denser propellant tank on the top of the stage (examples H2, Ariane V, Shuttle, Delta IV) thus keeping the CG well forward.

With a mono-prop tank the CG will move well aft as it drains. Thinking of it this way, when half the prop is expended the CG will now be in the back quarter of the vehicle while still experiencing large aero loads. How much will the nose hunt?

[mlorrey]

How big of a problem will shifting CG be in a first stage?

With bi-Prop first stages you often place the denser propellant tank on the top of the stage (examples H2, Ariane V, Shuttle, Delta IV) thus keeping the CG well forward.

With a mono-prop tank the CG will move well aft as it drains. Thinking of it this way, when half the prop is expended the CG will now be in the back quarter of the vehicle while still experiencing large aero loads. How much will the nose hunt?

You would need the tank to taper inward toward the bottom.

[baldusi]

You would need the tank to taper inward toward the bottom.

Or add a common bulkhead and drain first the bottom one. But this is usually a problem for atmospheric LV, and NOFBX seems to be used for small engines and satellites.

[kevin-rf]

Note my question was for a first stage, which implies atmospheric flight.

If the ISP is that high, and it is that easy to handle, it would make an excellent first stage. And that is why I was asking, will the amount the CG wanders make it difficult to use as a first stage?

It is great for in-space use, upper stage use, lunar lander, mars sample return, but would it work as a first stage.

Notice they are very keen on using aero-spikes! Which are also excellent for first stages.

[simonbp]

WRT to CoG shifting: a wide, short first stage would minimize the shift, and be better set up for a truncated aerospike at the base. Sortta like the old GD & Martin Nova proposals, but smaller-scale...

[kevin-rf]

Well, short and fat, as opposed to tall and thin with a mono-propellant does give you a better mass fraction...

[baldusi]

Well, short and fat, as opposed to tall and thin with a mono-propellant does give you a better mass fraction...

And a huge drag and terrible structural loads at MaxQ. There's a reason LV are thin and tall.

[KelvinZero]

I have wondered about that. Apart from being tall and thin, rockets do not look that streamlined the way a fighter jet is for example. Also, what about the shuttle? If tall and thin is good then you couldn't get much worse.

[93143]

Google "Sears-Haack" and take a look at the integrated wave drag formula.  Tall and thin is extremely important.

Also, the Shuttle could get considerably worse.  Its shape is a compromise between good ascent performance and good reentry performance.  Thin, sharp shapes are really bad for reentry.

Rockets tend not to be absolutely optimized for low-drag supersonic flight because they only spend a small fraction of the ascent in the high-drag regime, and drag losses are generally much smaller than gravity losses anyway.

[KelvinZero]

Hi 93143,

As far as I can see you are saying tall and thin is extremely important, but sometimes we don't bother with much of it because we want some other stuff and besides drag only matters in the lower atmosphere and drag losses are generally much smaller than gravity losses also. Thanks for clearing that up

If you wanted a good compromise between ascent performance (narrow?) and reenty performance (wide?) wouldn't you fight hard for an inline design?

[RanulfC]

Note on rocket design;
Short and fat is NEVER a "good" shape for a small rocket HOWEVER there are "ways" around the issue.

As one example the LLNL proposed "Mocking Bird" SSTO-demonstrator vehicle was mostly fuel tankage placed over a clustered-plug-nozzle engine assembly. Since this wasn't the most aerodynamic set up (short and squat) they placed the majority of flight instruments and gear and a portion of the payload under a VERY sharp cone that was almost twice the "length" of the rest of the vehicle. It was also mostly empty space as all the "mass" was placed at the bottom of the cone.

Another example is the proposed Chrysler SERV launch vehicle which can in NO way be called aerodynamicly "optimized"
(Think an Apollo capsule the as tall as a Saturn-V and go from there )

In order to get around the high-drag at Max-Q imposed by the design the SERV would have used a "aero-spike" device consisting of what amounts to a specially shaped "pole" on the nose that would induce supersonic and hypersonic shock-waves that would be directed around the majority of the vehicle during ascent.

The concept worked in testing but there were some questions as to the feasability of actually mounting and launching with such a large "boom" on the vehicle. There would be "less" issues with a smaller vehicle of course.

Randy

[kevin-rf]

In order to get around the high-drag at Max-Q imposed by the design the SERV would have used a "aero-spike" device consisting of what amounts to a specially shaped "pole" on the nose that would induce supersonic and hypersonic shock-waves that would be directed around the majority of the vehicle during ascent.

The concept worked in testing but there were some questions as to the feasability of actually mounting and launching with such a large "boom" on the vehicle. There would be "less" issues with a smaller vehicle of course.

Randy

I believe Trident uses the same trick... and that is an operational SLBM.

[RanulfC]

In order to get around the high-drag at Max-Q imposed by the design the SERV would have used a "aero-spike" device consisting of what amounts to a specially shaped "pole" on the nose that would induce supersonic and hypersonic shock-waves that would be directed around the majority of the vehicle during ascent.

The concept worked in testing but there were some questions as to the feasability of actually mounting and launching with such a large "boom" on the vehicle. There would be "less" issues with a smaller vehicle of course.

Randy

I believe Trident uses the same trick... and that is an operational SLBM.

It does actually.... Now imagine sticking that same "little" pear-shaped "spike" on the end of around 100' of metal telephone pole

Randy

[simonbp]

Well, in the case of the latter SERV designs, the "spike" was an HL-20-sized shuttle...

But, what I really meant was a squarish first stage (length ~ diameter), topped with a comparable-sized LH2 second stage. The density difference between the two stages would be such that the liftoff thrust wouldn't need to be too high...

[RanulfC]

Well, in the case of the latter SERV designs, the "spike" was an HL-20-sized shuttle...

But, what I really meant was a squarish first stage (length ~ diameter), topped with a comparable-sized LH2 second stage. The density difference between the two stages would be such that the liftoff thrust wouldn't need to be too high...

Actually the "spike" was going to be used when they DIDN'T fly the "MURP" shuttle and JUST had "internal" cargo.

It's a good possible idea as far as I can see as long as the overall aerodynamics keep the upper stage aligned at the start. That's of course where the differential throttling of the plug-cluster comes in

As for depot use, having read a bit further in the patent:
http://www.freepatentsonline.com/y2009/0133788.pdf

There seems to be multiple "blends" depending on the engine type being used. There is also the issue of KEEPING the propellant blended and how long it can remain in storage, though from the presentation it would seem they are confident it will be both long-term storable AND stable.

Hope to hear more information soon...

Oh, and here is the patent on their new engine cooling scheme:
http://www.freepatentsonline.com/y2010/0205933.pdf

Randy

[neilh]

Apparently Max Vozoff gave a talk on NOFBX and Firestar, liveblogging here:

http://forum.nasaspaceflight.com/index.php?topic=24728.msg720878#msg720878
http://www.transterrestrial.com/?p=33007
http://www.hobbyspace.com/nucleus/index.php?itemid=28537

[sdsds]

An Isp of 320 sec is getting into the LOX/CH4 range, but with much, much less hassle. [...]  This actually seems like an ideal propellant for a depot. It's high enough Isp to useful, apparently storable over a wide range, and allows you to consolidate the depot down to a single fluid...

Maybe ideal for a lunar-vicinity depot.  Do you agree 320 sec is probably not useful for LEO departure?  (Even the ~340 sec possible with pump-fed hypergolic propellants makes for difficult LEO departures.)

[IsaacKuo]

An Isp of 320 sec is getting into the LOX/CH4 range, but with much, much less hassle. [...]  This actually seems like an ideal propellant for a depot. It's high enough Isp to useful, apparently storable over a wide range, and allows you to consolidate the depot down to a single fluid...

Maybe ideal for a lunar-vicinity depot.  Do you agree 320 sec is probably not useful for LEO departure?

It could easily be good enough if you use multiple depots--one at LEO along with another one or two in elliptical orbits.

But I think the true holy grail is in situ resource utilization.  NOFBX sounds like nitrous oxide fuel blend...does that mean that it is largely composed of nitrous oxide?  If so, then an atmospheric scooping satellite could harvest air from the upper atmosphere and use it to produce nitrous oxide.  This means that most of the mass of the propellant doesn't have to be launched from the surface.

The design of an atmospheric scooping satellite would be similar to GOCE, but with a scoop in front and a nitrogen ion thruster in back (it uses a normal xenon ion thruster in the tail to counteract atmospheric drag).

[cuddihy]

But I think the true holy grail is in situ resource utilization .  NOFBX sounds like nitrous oxide fuel blend...does that mean that it is largely composed of nitrous oxide?

I guess the "X" is to make it cool?

  If so, then an atmospheric scooping satellite could harvest air from the upper atmosphere and use it to produce nitrous oxide.

  This means that most of the mass of the propellant doesn't have to be launched from the surface.

Reading too much Fallen Angels. At non-drag limited altitudes there's not whole lot of nitrogen. And it's a bit like trying to power a car with a windmill on top --- unless you're using a propellantless system like an electrodynamic tether, you lose more mass in fuel staying in orbit than you gain in mass collected from "scooping." Because you're forgetting about the drag associated with solar panels to keep your thruster powered.

The design of an atmospheric scooping satellite would be similar to GOCE, but with a scoop in front and a nitrogen ion thruster in back (it uses a normal xenon ion thruster in the tail to counteract atmospheric drag).

[IsaacKuo]

If so, then an atmospheric scooping satellite could harvest air from the upper atmosphere and use it to produce nitrous oxide.

  This means that most of the mass of the propellant doesn't have to be launched from the surface.

Reading too much Fallen Angels. At non-drag limited altitudes there's not whole lot of nitrogen. And it's a bit like trying to power a car with a windmill on top --- unless you're using a propellantless system like an electrodynamic tether, you lose more mass in fuel staying in orbit than you gain in mass collected from "scooping." Because you're forgetting about the drag associated with solar panels to keep your thruster powered.

Assuming an exhaust velocity of 40km/s, like GOCE's thruster, there is plenty of excess impulse for each kilogram of collected nitrogen.  You would only need to exhaust 1kg out of every 5kg collected to maintain orbit.  Certainly GOCE had enough solar power to make up for its drag (up to its propellant supply).

There are two obvious ways to practically eliminate solar panel drag from being a factor.  One is to use scoops big enough to "hide" the solar panels entirely behind the scoops.  This may imply a significant scoop mass and more of a technical challenge compressing/cooling the more rarefied air.

The other way is to use a somewhat elliptical orbit so scooping takes place at perigee.  This gives the solar electric propulsion system more time to provide reboost impulse to make up for the drag during perigee.

[cuddihy]

Not really, because orbital mechanics says if you boost away from perigee, you will raise perigee. The drag brings down your apogee, not perigee. So you have to overcome drag only while at perigee.

[Hop_David]

Not really, because orbital mechanics says if you boost away from perigee, you will raise perigee.

You seem to be assuming the burn must be horizontal. This doesn't have to be the case.

[mlorrey]

Not really, because orbital mechanics says if you boost away from perigee, you will raise perigee. The drag brings down your apogee, not perigee. So you have to overcome drag only while at perigee.

Ah, no, when you boost at perigee, that raises apogee. Boosting at apogee raises perigee.

[Comga]

Scooping atmospheric gasses is a non-starter.  The gas would have to be accelerated to orbital speeds by the scoop, which would need to be powered to compensate.   There is no free lunch here.  Maybe in the "Advanced Concepts" section.  ;-)

Back to NOFBX?

[Hop_David]

Scooping atmospheric gasses is a non-starter.  The gas would have to be accelerated to orbital speeds by the scoop, which would need to be powered to compensate.   There is no free lunch here.  Maybe in the "Advanced Concepts" section.  ;-)

Kuo's already addressed that. The exhaust velocity of the ion engine's reaction mass would be well above the 8 km/sec orbital speed. So a fraction of the air mass scooped would suffice to preserve orbital momentum.

[MikeAtkinson]

My naive analysis says that if the characteristics are as stated, NOFBX used in a SSTO (non-reusable) should be able to place 1-2% of the GTOW into orbit (with a stage propellant mass fraction of 97%). A second stage would be needed for GTO.

A single tank, simpler plumbing, lightweight simple engine should all improve things over Kero/LOX. Being a single stage it would have maybe 1/4 of the parts count of a 2 stage Kero/LOX like F1e.

The engine would need to be deep throttled, but that is supposedly possible on the smaller engines they have tested so far.

I'm not sure but I think you can virtually eliminate propellant residuals. Add a small gaseous thruster which burns the remaining gaseous propellant used for self pressurisation, as that is burn any remaining liquid will evaporate.

[93143]

The exhaust velocity of the ion engine's reaction mass would be well above the 8 km/sec orbital speed. So a fraction of the air mass scooped would suffice to preserve orbital momentum.

No, a fraction of the air mass encountered would suffice.  Your scoop would have to be a significant portion of the total frontal area of the vehicle, including the solar panels.

[IsaacKuo]

Not really, because orbital mechanics says if you boost away from perigee, you will raise perigee. The drag brings down your apogee, not perigee. So you have to overcome drag only while at perigee.

Assuming you thrust in the direction of your orbital path, this is true.  However, the degree to which you raise perigee is very small so long as you only do this within, say, 60 degrees of perigee.

One way to factor this in is to thrust in the direction of your orbital path for the 120 degree arc centered around perigee, and then thrust against your orbital speed briefly at apogee to push perigee back down.  It doesn't take much.

[IsaacKuo]

The exhaust velocity of the ion engine's reaction mass would be well above the 8 km/sec orbital speed. So a fraction of the air mass scooped would suffice to preserve orbital momentum.

No, a fraction of the air mass encountered would suffice.  Your scoop would have to be a significant portion of the total frontal area of the vehicle, including the solar panels.

Look at the design of GOCE.  The solar panels are edge on to the flight path, minimizing drag.  The frontal area is minimal.

Nevertheless, there is a lower limit on drag even with the minimal frontal area of edge-on panels.  The thermal motion of air molecules means that they'll still have some transverse motion--so some air molecules wil still hit the broad sides of a perfectly edge on panel.  To truly hide the panels behind a large scoop, they would have to fit within an inverted conical "shadow" behind the scoop's mouth.  In other words, the "shadow" doesn't have parallel walls, but rather tapers inward.

[cuddihy]

Not really, because orbital mechanics says if you boost away from perigee, you will raise perigee. The drag brings down your apogee, not perigee. So you have to overcome drag only while at perigee.

Ah, no, when you boost at perigee, that raises apogee. Boosting at apogee raises perigee.

yeah, I typoed exactly what I was trying to get across, making the situation worse ...perils of iPhoning ... you get the point, if you can't correct for drag while it is happening, you will not remain in the same eccentric orbit.

[IsaacKuo]

... you get the point, if you can't correct for drag while it is happening, you will not remain in the same eccentric orbit.

You certainly can remain in the same elliptical orbit, and I describe one way to do it.

[Comga]

So they claim that NOFBX is:
High performing (ISP=320s)
Non-toxic
Stable

and they have engines with:
Light weight
Low complexity
Anti-backflash
A variety of thrust levels
Pulse capabilities

and you are talking about making it for free in the exosphere with a giant scoop?
Isn't that a bit greedy?
Does every thread have to fly into and through the blue sky?

What I want to know is how to get my colleagues looking into this.  For that I need more practical information on and evaluation of the current progress.

[MikeAtkinson]

What I want to know is how to get my colleagues looking into this.  For that I need more practical information on and evaluation of the current progress.

Contact Max Vozoff and IPS directly. Ask for a tech demo.

[RanulfC]

But I think the true holy grail is in situ resource utilization.  NOFBX sounds like nitrous oxide fuel blend...does that mean that it is largely composed of nitrous oxide?

(Answering the original question :::grin:::

YES, NOFB (no-X actually as it seems to be representive of a place holder for a "number" assigned to each 'blend' examples: NOFB36, NOFB34, etc. See patent) stands for "Nitrous Oxide FUEL BLEND" the "mono-propellant" being a blend of NO2 and various fuels such as ethelyne, or ethane, AND possible "additive" fuels such as BOTH ethelyne and ethane to allow for "self-pressurization" process'.

Quite interesting stuff really.

Randy

[yg1968]

On page 5 of the Selection Statement, it says that Boeing intends to use non-toxic propellant for the CST-100 crew module. I imagine that this means that they intend to use the NOFBX monopropr system.

http://procurement.ksc.nasa.gov/documents/SelectionStatement-Final_Signed.pdf

See also:
http://forum.nasaspaceflight.com/index.php?topic=22125.msg726057#msg726057

Is there any other details on this?

[Jim]

On page 5 of the Selection Statement, it says that Boeing intends to use non-toxic propellant for the CST-100 crew module. I imagine that this means that they intend to use the NOFBX monopropr system.

http://procurement.ksc.nasa.gov/documents/SelectionStatement-Final_Signed.pdf

See also:
http://forum.nasaspaceflight.com/index.php?topic=22125.msg726057#msg726057

Is there any other details on this?

it could mean a lot of things.  GOX/methane, GOX/alcohol, etc.   It doesn't say monopropellant

[yg1968]

Perhaps but according to Greg Mundas, ISP Systems were working with 4 potential CCDev-2 candidates looking at requirements for retrofitting this NOFBX sytem as their spaceceraft's propulsion.

See page 18:
http://www.aiaa.org/pdf/industry/presentations/Greg_Mungas.pdf

See also:
http://forum.nasaspaceflight.com/index.php?topic=24352.msg703543#msg703543

[MikeAtkinson]

On page 5 of the Selection Statement, it says that Boeing intends to use non-toxic propellant for the CST-100 crew module. I imagine that this means that they intend to use the NOFBX monopropr system.

http://procurement.ksc.nasa.gov/documents/SelectionStatement-Final_Signed.pdf

See also:
http://forum.nasaspaceflight.com/index.php?topic=22125.msg726057#msg726057

Is there any other details on this?

It says on page 1a-31 "ONA propellant", I've no idea what ONA means, google does not seem to come up with anything sensible.

[RanulfC]

On page 5 of the Selection Statement, it says that Boeing intends to use non-toxic propellant for the CST-100 crew module. I imagine that this means that they intend to use the NOFBX monopropr system.

http://procurement.ksc.nasa.gov/documents/SelectionStatement-Final_Signed.pdf

See also:
http://forum.nasaspaceflight.com/index.php?topic=22125.msg726057#msg726057

Is there any other details on this?

It says on page 1a-31 "ONA propellant", I've no idea what ONA means, google does not seem to come up with anything sensible.

Sure it does! ANYTHING having the word combination "...on...a..." comes up, what that's NOT helpful?

Ya, I can't find anything either even trying looking at various "green-propellant" papers doesn't have THAT exact combination so there isn't any real way of telling what they are talking about.
(Which in retrospect isn't exactly unusual for most companies in public documents )

Does this "mean" they are looking at NOFB? Given Boeing's usual timidity, probably not. However it's always possible. I suspect we won't "know" till someone actually says one way or another though

Randy

[MP99]

It says on page 1a-31 "ONA propellant", I've no idea what ONA means, google does not seem to come up with anything sensible.

Sure it does! ANYTHING having the word combination "...on...a..." comes up, what that's NOT helpful?

Ya, I can't find anything either even trying looking at various "green-propellant" papers doesn't have THAT exact combination so there isn't any real way of telling what they are talking about.
(Which in retrospect isn't exactly unusual for most companies in public documents )

Does this "mean" they are looking at NOFB? Given Boeing's usual timidity, probably not. However it's always possible. I suspect we won't "know" till someone actually says one way or another though

Don't search for:-
ONA

search instead for:-
"ONA"
   or
"ONA" propellant
   or
"ONA propellant"

Google treats double quotes as "find exactly this". The third one finds only two results, one being the KSC doc.

The second one looks quite promising if you fancy having another go.

cheers, Martin

[baldusi]

On page 5 of the Selection Statement, it says that Boeing intends to use non-toxic propellant for the CST-100 crew module.

Have you seen the animation? The LAS plus propulsion appears to be a sort of Service Module that's dumped just before reentry. I wouldn't be surprised if the "crew module" only have some cold gas thrusters.

[RanulfC]

It says on page 1a-31 "ONA propellant", I've no idea what ONA means, google does not seem to come up with anything sensible.

Sure it does! ANYTHING having the word combination "...on...a..." comes up, what that's NOT helpful?

Ya, I can't find anything either even trying looking at various "green-propellant" papers doesn't have THAT exact combination so there isn't any real way of telling what they are talking about.
(Which in retrospect isn't exactly unusual for most companies in public documents )

Does this "mean" they are looking at NOFB? Given Boeing's usual timidity, probably not. However it's always possible. I suspect we won't "know" till someone actually says one way or another though

Don't search for:-
ONA

search instead for:-
"ONA"
   or
"ONA" propellant
   or
"ONA propellant"

Google treats double quotes as "find exactly this". The third one finds only two results, one being the KSC doc.

The second one looks quite promising if you fancy having another go.

Actually no help at all really, (the pictures of the actress from Stargate ARE promsing though ) the ONLY thing that comes up seems to be a typing error:
http://www.patentgenius.com/patent/5468311.html

"ona" seeming to actually have meant to be "on a"

Randy

[RanulfC]

A "tad" more information overall from the upcoming May issue of Air&Space magazine.
Article entitled: The Mojave Launch Lab, (Page-3/4)

When Apollo astronauts lifted off the moon, they left behind a lot of things besides footprints. Toxic hydrazine fuel contamination was one. Not a problem—nobody was returning soon. But for repeat visits to a lunar or Mars base, Greg Mungas says, “Having a non-toxic propellant will be a big deal.”

A former Jet Propulsion Laboratory engineer, Mungas formed Firestar Technologies and moved to Mojave to make rocket science greener. “We started playing around with the idea of blending fuels with nitrous oxide for deep-space applications,” he says. A research contract from NASA’s Mars Advanced Technology Program resulted in NOFBX, Firestar’s patented mono-propellant.

“Nitrous oxide just decomposes into oxygen-rich air,” Mungas says. And monopropellants don’t require separate tanks of liquid oxygen. Mungas likens the propellant to “the propane bottle you take on camping trips,” something that fuels the camp stove, lights lanterns, and runs a generator. NOFBX from the tank that fuels a spacecraft’s rockets could also generate onboard electricity and drive turbine-powered equipment on a planet’s surface.

For a contract with the Defense Advanced Research Projects Agency, Firestar developed a NOFBX-fueled piston engine for high-altitude, long-endurance drones. “It’s the unmanned equivalent of the U-2 spyplane,” Mungas says. Piston engines, powering everything from generators to small aircraft, have been modified in-house to run at altitudes with almost no oxygen.

Firestar engineers Ken Doyle and Greg Peters show me around the spaceport test site, north of the runways. “Big bangs happen here all the time,” Doyle says. “You never know whether it’s something at the [Soledad Mountain] gold mine over there or a test in progress.” Firestar’s site includes a 40-foot drop tower to shock-test propellants and a burn pit to cook them. A static stand for 10,000-pound-thrust engines throws fire out toward the scrub. “Depending on the amount of stuff that might explode,” Doyle says, the control room—an air-conditioned, computer-equipped, microwave-linked, steel shipping container—can be transported to safe distances.

Not everything else can. “My cousin’s got an old Firebird up on blocks,” says Greg Peters. “I tell him, ‘Guess what I’ve got up on blocks?’ It’s an 80,000-pound vacuum chamber made by General Dynamics in the 1960s to simulate deep space for satellites.” Mungas, who rescued the behemoth from a San Diego boatyard, is renovating the rare asset. Says Peters: “We can put sand and rocks inside, pump it down to Mars pressure, backfill it with CO2, and essentially create the Mars environment. Right here in Mojave.”

No real info but the overall article is quite good as the author talks to most of the various players at Mojave.

http://www.airspacemag.com/space-exploration/The-Mojave-Launch-Lab.html?c=y&page=3

Randy

[Robotbeat]

If so, then an atmospheric scooping satellite could harvest air from the upper atmosphere and use it to produce nitrous oxide.

  This means that most of the mass of the propellant doesn't have to be launched from the surface.

Reading too much Fallen Angels. At non-drag limited altitudes there's not whole lot of nitrogen. And it's a bit like trying to power a car with a windmill on top --- unless you're using a propellantless system like an electrodynamic tether, you lose more mass in fuel staying in orbit than you gain in mass collected from "scooping." Because you're forgetting about the drag associated with solar panels to keep your thruster powered.

Assuming an exhaust velocity of 40km/s, like GOCE's thruster, there is plenty of excess impulse for each kilogram of collected nitrogen.  You would only need to exhaust 1kg out of every 5kg collected to maintain orbit.  Certainly GOCE had enough solar power to make up for its drag (up to its propellant supply).

There are two obvious ways to practically eliminate solar panel drag from being a factor.  One is to use scoops big enough to "hide" the solar panels entirely behind the scoops.  This may imply a significant scoop mass and more of a technical challenge compressing/cooling the more rarefied air.

The other way is to use a somewhat elliptical orbit so scooping takes place at perigee.  This gives the solar electric propulsion system more time to provide reboost impulse to make up for the drag during perigee.

The method I've thought of is to just have the scoop hanging down a couple dozen or so miles below the solar array, a few "scale atmosphere heights" so the density is far, far less at the solar array than at the scoop.

It'd work a heck of a lot better around Mars, where the orbital velocity is much lower. Have to use CO/O2 for rocket fuel, though.

[RanulfC]

Possible issue with NOFB and fuel depots is that it has to be "blended" for specific engines so that the blend for thrusters won't work on main-engines and so on.

Randy

[RobLynn]

The method I've thought of is to just have the scoop hanging down a couple dozen or so miles below the solar array, a few "scale atmosphere heights" so the density is far, far less at the solar array than at the scoop.

It'd work a heck of a lot better around Mars, where the orbital velocity is much lower. Have to use CO/O2 for rocket fuel, though.

Why not just line the scoop craft up in a sun sychronous orbit so that the solar panels are permanently parallel to the direction of travel - they are very thin and hence won't have much drag, Tidal forces should keep everything aligned nicely.

Hanging the scoop on the end of a tether is also a good idea.

[IsaacKuo]

Why not just line the scoop craft up in a sun sychronous orbit so that the solar panels are permanently parallel to the direction of travel - they are very thin and hence won't have much drag, Tidal forces should keep everything aligned nicely.

I have suggested that.  Look at the design of GOCE for an example.

Unfortunately, this does not eliminate drag.  The thermal motion of the atmosphere's molecules means that they will have a significant transverse component.  They'll still hit the sides.  Drag is reduced but by not eliminated.

Hanging the scoop on the end of a tether is also a good idea.

Such a tether would suffer a good deal of drag.

[Space Pete]

This is old news, but I only just came across and I haven't seen it posted here before. It seems that NOFBX will be demonstrated on ISS (and you all know how much I love ISS)!

--------------------

NOFBX® and ISS National Lab

March 24, 2011: We are pleased to announce that Odyssey is part of the winning Innovative Space Propulsion Systems (ISPS) team selected to develop and perform a NOFBX® flight experiment at the International Space Station in late 2012. The award was made under the ISS National Lab Broad Agency Announcement. Odyssey will perform flight support equipment development and integration, as well as flight software, operations, and key administrative and programmatic functions. To read more about the ISPS flight experiment, go to: http://www.ispsllc.com.

http://www.odysseysr.com/news.html#2011-03-24

[Comga]

What I want to know is how to get my colleagues looking into this.  For that I need more practical information on and evaluation of the current progress.

Contact Max Vozoff and IPS directly. Ask for a tech demo.

Oh, I could find Mr Vozoff pretty easily, even without Google.     
It's getting my colleagues to consider this.  My limited inquiries have not been productive, at least not yet.

[Space Pete]

More on the NOFBX ISS demo:

http://blogs.nasa.gov/cm/blog/ISS%20Science%20Blog/posts/post_1307128426352.html

[docmordrid]

Looked through the patent and came up with their mix naming convention-

NOFBX: Nitrous Oxide Fuel Blend

1st digit: C2 hydrocarbon group

1: ethane
2: ethylene
3: acetylene

2nd digit: Oxidizer to Fuel ratio

3rd character: blend variation suffix (additives etc.): a,b,c,d.....

NOFBX34a: nitrous oxide + acetylene with a 4:1 oxidizer to fuel ratio and their first listed mix variation

[docmordrid]

Patent PDFs:

Flashback preventer: link....

Rocket engine injector head: link....

Flashback shutoff: link....

Spark-integrated injector: link....

Insulated combustion chamber (I/C engine): link....

Detonation wave arrestor: link....

Aluminum porous media: link....

Regeneratively cooled aluminum porous media jacket: link....

[krytek]

This sounds like a great stuff.

Do you think a it can be used as a first/second stage propellant?

[docmordrid]

I'd defer to the real propulsion guys for that.

The largest thruster mentioned in their literature is a 10,000 lbf unit they are proposing for a CCDev-2 companies launch abort system - and right next to that blurb is a pic of SpaceX's Dragon.

[strangequark]

This sounds like a great stuff.

Do you think a it can be used as a first/second stage propellant?

This is where I put on my cynical, gray-haired engineer's hat. It almost certainly can. The bigger question is should it, and is it worth it. Your advantage is that it's a monopropellant, so you have a possibly simpler engine. Your disadvantages are:

High vapor pressure propellant
Intoxicant (bad when combined with the above)
Potentially a Class 1.1 material (mass detonation)
Combustion stability (premixed propellants tend to have issues)
Non-catalytic
Large development costs

That last one is the keystone. A new technology must be substantially better than its established competitor to justify the costs of the switch.

HAN has been playing this game for a while. It's non-toxic, and the only volatile is gives off is water vapor. However, hydrazine is very well established, stable, low vapor pressure, high density, has an effective room temperature catalyst, has consistent pulse performance, has a reaction temperature in the nickel-alloy sweet spot, has mild exhaust products, can be used in dual-mode systems.

The only reason HAN has a chance of being used on flight hardware is because it has great Isp, and is very high density. NOFBX has comparable Isp, but much worse density, high vapor pressure is not desirable (self-pressurizing is PR babble), and high flame temp. Between the flame arresters, regenerative cooling and/or exotic materials, spark igniter, low density, and strongly temperature dependent tank pressure, I would just about bet my dog that a biprop system would be simpler.

[john smith 19]

This is where I put on my cynical, gray-haired engineer's hat. It almost certainly can. The bigger question is should it, and is it worth it. Your advantage is that it's a monopropellant, so you have a possibly simpler engine. Your disadvantages are:

High vapor pressure propellant
Intoxicant (bad when combined with the above)
Potentially a Class 1.1 material (mass detonation)
Combustion stability (premixed propellants tend to have issues)
Non-catalytic
Large development costs

That last one is the keystone. A new technology must be substantially better than its established competitor to justify the costs of the switch.

HAN has been playing this game for a while. It's non-toxic, and the only volatile is gives off is water vapor. However, hydrazine is very well established, stable, low vapor pressure, high density, has an effective room temperature catalyst, has consistent pulse performance, has a reaction temperature in the nickel-alloy sweet spot, has mild exhaust products, can be used in dual-mode systems.

The only reason HAN has a chance of being used on flight hardware is because it has great Isp, and is very high density. NOFBX has comparable Isp, but much worse density, high vapor pressure is not desirable (self-pressurizing is PR babble), and high flame temp. Between the flame arresters, regenerative cooling and/or exotic materials, spark igniter, low density, and strongly temperature dependent tank pressure, I would just about bet my dog that a biprop system would be simpler.

Good list. People seem to forget that while MMH/NTO/UDMH are nasty and expensive their properties are well understood and there are huge *sunk* costs already paid. Buying better Isp at the cost of an ignition system seems like a *large* gamble for someone building say a comms sat with a 10 year life.

I've seen occasional references (mentioned in passing) to a catalyst for NOX, but AFAIK it's normally thermally decomposed, which gets us back to an ignition system. IIRC HAN does have catalysts available for it.

As it's not hypergolic and there's no catalyst you might as well stay with something already known.

BTW has anyone noticed they are saying their test will use Acetylene (I think we should start using its proper chemical name Ethyne) for their first test?

This should give the best performance of the HC's listed and (not sure) there *might* be a catalyst that generates enough heat to trigger NOX breakdown.

Then again I think it's also prone to detonating on impact.

I can't shake the feeling this is one of those ideas that mistakes different for better.  but it has got some traction so the outcome should be interesting.

As for stage 1 or 2 propulsion I guess that would depend how serious a designer rates the problems of LOX storage. I suppose it would make, say a magnesium alloy tank easier (which were used on Vanguard).

Sometimes I'm just amazed at what does and does not get funding.

[yg1968]

BAA for demonstrations of propulsion systems utilizing green propellant alternatives to hydrazine:

FY12 OCT Space Technology Funding:  For individual awards under this BAA, the total OCT ST funding of life cycle costs may not exceed $50 million. Higher OCT ST funding may be considered in exceptional cases offering a particularly compelling technological capability that warrants a higher funding level.

http://prod.nais.nasa.gov/cgi-bin/eps/sol.cgi?acqid=149757

http://www.nasa.gov/mission_pages/tdm/main/H-12-046.html

[Enthalpy]

Nitrous oxide N₂O detonates. While not very sensitive, it has already killed a worker at Virgin Galactic.
Acetylene detonates, by shock, contact with metals... Sensitive: 3 of 4 on the risk sign. That's why torches use it dissolved in acetone instead of compressed to a liquid in a bottle.

People who developed rocket technology decades ago went away from such chemicals. Apparently this knowledge has been lost, with new desires and trials with acetylene, propyne, nitrous oxide, ethylene, propylene... and consequently accidents, with N₂O.

All these have no place in a launcher, far less in kiloton quantity at lower stages.

[simonbp]

Well yes, that's the point of NOFBX. It premixes two nasty chemicals with a stabilizer blend so that they don't detonate when you don't want them to. At Space Access last year, they said they were going through the full MILSPEC qualifications and were doing better on stability so far than hydrazine, the fuel they are seeking to replace.

The real use of propellants like NOFBX, HAN, etc are for in-space applications where you don't want to do anything special to keep them stored for years at a time, but have them in close proximity to either pristine surfaces (e.g. Mars) or human lungs.

[docmordrid]

And, as noted upthread, NOFBx doesn't have to be an acetylene  blend. It can use ethane or ethylene as well.

[strangequark]

Well yes, that's the point of NOFBX. It premixes two nasty chemicals with a stabilizer blend so that they don't detonate when you don't want them to. At Space Access last year, they said they were going through the full MILSPEC qualifications and were doing better on stability so far than hydrazine, the fuel they are seeking to replace.

Were they specific as to the types of tests? The only one I've seen them mention is 40-foot drop. I was a little soured by them using that as their benchmark example of stability, which has given me a big old dose of skepticism about NOFBX (in addition to some professional bias). I've seen nitrocellulose pyrotechnics go through a 40-foot drop, and I wouldn't call nitrocellulose a stable compound.

[docmordrid]

NOFBX has now been given clearance to be tested at the International Space Station, and  go up in a Dragon late this year or early next year.

http://www.aviationw...-458579.xml&p=1

[JBF]

Your link is broken, here is a better one.

http://www.aviationweek.com/Article.aspx?id=/article-xml/AW_05_21_2012_p24-458579.xml

[jmiraglia]

Double base propellant - nitrocellulose + nitroglycerin

This propellant is perfectly stable

http://www.astronautix.com/articles/doulants.htm

NOFBX is perfectly stable.

Nitromethane can detonate and is widely used in cars, dragster and RC models.
Hidrazine detonates and is also widely used.
The book "Ignition" is an excellent reference.

Miraglia
www.edgeofspace.org

[strangequark]

Double base propellant - nitrocellulose + nitroglycerin

This propellant is perfectly stable

http://www.astronautix.com/articles/doulants.htm

NOFBX is perfectly stable.

Nitromethane can detonate and is widely used in cars, dragster and RC models.
Hidrazine detonates and is also widely used.
The book "Ignition" is an excellent reference.

Miraglia
www.edgeofspace.org

Double base propellant is safe, when properly treated under the right protocols. It is not perfectly stable. It's susceptible to initiation by electrostatic discharge, friction, and "pinching". You missed my point. The 40 foot drop test they cite is a standard pyrotechnic handling test, to ensure that a device will not go off if someone slips and drops the thing off of a catwalk. It's not all that applicable to the stability of a liquid propellant running through a pressure fed engine, and isn't a valuable indicator of overall stability. You don't know if NOFBX is stable. What needs to be characterized is the propellant's sensitivity to ignition due to waterhammer, temperature, and contamination catalyzed runaway, among other things. Hydrazine and Nitromethane are both well characterized for their operating environments. "Non-toxic" is only one small part of the puzzle, and just because a propellant is "green", doesn't mean it gives any measurable benefit to operational safety.

That's why I was asking if anyone has detail on what other tests they've done, because 40 foot drop is a PR stunt. "Full MILSPEC qualifications" has no meaning, unless you identify the document and test set. That is, I presume they're not performing a MIL-STD-810 salt fog test.

[vulture4]

Hydrazines are highly soluble in water and the new propellant is a major advance in that it contains enough water to keep the vapor pressure at a minimal level while not interfering with decomposition as a monopropellant. Consequently respiratory hazards are avoided, respiratory PPE is not required and handling is much less expensive, though it is not 'nontoxic' per se. As with most combustion engines (including cars) the exhaust does contain toxic combustion products.

[go4mars]

Has this already been launched to the ISS?  Or is that still upcoming?

[yg1968]

It's suppose to launch on the CRS-3 flight.

See this link:
http://forum.nasaspaceflight.com/index.php?topic=25396.msg874140#msg874140

[docmordrid]

NOFBX fueled SSTO Mars Ascent Vehicle....(sample return)(PDF)

http://sbir.gsfc.nasa.gov/SBIR/abstracts/11/sbir/phase2/SBIR-11-2-O2.02-8647.html

NASA SBIR 2011 Solicitation

FORM B - PROPOSAL SUMMARY

PROPOSAL NUMBER:   11-2 O2.02-8647
PHASE 1 CONTRACT NUMBER:   NNX12CD56P
SUBTOPIC TITLE:   Propulsion Technologies
PROPOSAL TITLE:   Low Energy Electronic Ignition System for NOFBX Thrusters
SMALL BUSINESS CONCERN (Firm Name, Mail Address, City/State/Zip, Phone)
Firestar Engineering, LLC
1122 Flightline Street, #76
Mojave, CA 93501 - 1610
(661) 860-1088

PRINCIPAL INVESTIGATOR/PROJECT MANAGER (Name, E-mail, Mail Address, City/State/Zip, Phone)
Greg S Mungas
[email protected]
1122 Flight Line Street
Mojave, CA 93501 - 1610
(626) 755-9919
Estimated Technology Readiness Level (TRL) at beginning and end of contract:
Begin: 3
End: 5

TECHNICAL ABSTRACT (Limit 2000 characters, approximately 200 words)
NOFBX propulsion technology is being developed actively for a number of applications including a flight experiment on the International Space Station NOFBX propellant has unique electrical properties that allow the potential for development of an extremely low energy ignition mechanism when coupled with the design of an NOFBX combustion chamber. This has the potential for dramatically reducing the volume, mass, voltage, and electromagnetic interference (EMI) emissions. The development we are proposing is a very low energy ignition system that utilizes the unique attributes of the NOFBXTM propellant that minimizes the volume, mass, and voltage of a block redundant system to be used in NOFBX propulsion systems.

POTENTIAL NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
The proposed igniter development is specific to NOFBX™ propellant-based systems. Unlike other liquid propellant options, NOFBX™ propellant has a low energy ignition threshold. Existing igniters are designed with much higher energy spark requirements to address the challenge of reliable ignition of other spark-ignited liquid propulsion technologies. Therefore, there are no igniters currently on the market that are well suited to NOFBX™ engines, which is the motivation for this proposal. Because this igniter would be manufactured and sold as part of NOFBX™ propulsion systems, the market for this technology is closely tied to adoption and use of NOFBX™ propulsion technology.

POTENTIAL NON-NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
NOFBX technology is currently being developed under a NASA BAA for flight on the International Space Station as a commercial flight experiment. The proposed activity would upgrade the ignition element of this flight system reducing mass, volume, and power of the device as well as conductive and radiative emission characteristics. Given the commercial interest in the NOFBX propulsion technology, we anticipate this block upgrade ignition module to be readily integrated into the NOFBX product line being developed by Innovation Space Propulsion Systems, the licensee of NOFBX technology.

TECHNOLOGY TAXONOMY MAPPING (NASA's technology taxonomy has been developed by the SBIR-STTR program to disseminate awareness of proposed and awarded R/R&D in the agency. It is a listing of over 100 technologies, sorted into broad categories, of interest to NASA.)

Ablative Propulsion
Atmospheric Propulsion
Extravehicular Activity (EVA) Propulsion
Fuels/Propellants
Launch Engine/Booster
Maneuvering/Stationkeeping/Attitude Control Devices
Spacecraft Main Engine
Surface Propulsion
Form Generated on 11-06-12 18:12

[JBF]

Any news on how the experimental payload for CRS-3 is going?

[Space Pete]

Any news on how the experimental payload for CRS-3 is going?

The NOFBX payload was bumped from the SpX-3 flight to SpX-4 in Jan 2014, however it has since been removed from that flight and has not yet been re-manifested for any downstream flight. Currently no word on if or when it will fly.

[docmordrid]

They're still working to get it on SPX-4

http://forum.nasaspaceflight.com/index.php?topic=31617.msg1038558#msg1038558

[Space Pete]

They're still working to get it on SPX-4

Or maybe not...

http://forum.nasaspaceflight.com/index.php?topic=25396.msg1038565#msg1038565

[cordwainer]

Question, if this does get near similar performance to LOX/CH4 then would this make a good candidate for OTRAG's original flat bulkhead Common Rocket Propulsion Unit design? A number of small flat and tapered bulkheads might eliminate some of the center of gravity problems mentioned.

[cordwainer]

It seems to me that  safe ignition is not the problem given the right chemical igniter or plasma ignition system. Similarly with the correct bulkhead  material design and geometry safe storage is not a problem either for a multi-stage launcher. Problem would be whether as mentioned it is self-pressurizing and therefore would eliminate the need or some of the need for turbochargers. I don't think it would make a great SSTO design but a CRPU type design might work. Any takers?

[cordwainer]

Multiple flat shaped CRPU's would also lend themselves well to a linear aerospike nozzle for higher pressurization and jettisoning off multiple CRPU's around a second and or third stage core of CRPU's would reduce drag as the rocket climbs in altitude. Getting enough thrust at launch might be a problem but you could probably fill the outer CRPU's that get ignited at launch with kerosene.

[cordwainer]

Theoretically could you use metal-mixing to increase thrust and reaction mass in a NOFBX propellant?

[Tetrakis]

Theoretically could you use metal-mixing to increase thrust and reaction mass in a NOFBX propellant?

NOFBX is already mixed with light hydrocarbons (ethane, ethene, acetylene; Nitrous Oxide "Fuel Blend") which react with the hot oxygen generated by decomposing nitrous oxide. Presumably the oxygen balance of the system is already fairly complete, so you would be trading metal for hydrocarbons. As I understand it, this fuel is useful primarily because it is liquid at ambient conditions and is fairly nontoxic. Emulsions of metal nanoparticles would probably oxidize at room temperature, and metal carbonyls like nickel tetracarbonyl are some of the most toxic gases on the planet.

[go4mars]

Still on for the 4th SpaceX resupply flight?

[cordwainer]

Sadly, I heard the ISS launch for testing a NOFBX RCS prototype was cancelled. Is there still any interest in NOFBX or has NASA decided to go with alternatives like H2O2, or aqueous solutions of HAN or ADN to replace hydrazine. Seems like NOFBX would have higher performance if they really have licked the storage and ignition issues. If you could store it safely for long periods of time could this make a good fuel for deep space missions to the Moon or Mars?

[yg1968]

I was trying to find updates on NOFBX. I couldn't find much except for a DARPA award in May 2013 and an article which are linked below:
https://www.fbo.gov/index?s=opportunity&mode=form&id=6fd716f982395f367272a747cb456636&tab=core&tabmode=list&=

http://docs.house.gov/meetings/SY/SY16/20131120/101534/HHRG-113-SY16-Wstate-WittS-20131120.pdf
http://www.parabolicarc.com/2013/11/21/stu-witts-prepared-remarks-congress-commercial-space/

Included in this technology portfolio, the Spaceport is the home of NOFBX™ green propulsion technology. NOFBX™ is one of the three competing technologies to eventually displace the current “gasoline” of the satellite community. (Europe has recently issued a 2016 ban on hydrazine due to its safe handling and disposal issues.) Due to its much higher performance than competing options, NOFBX™ technology has been selected for development for next generation, low cost, tactical launch systems like DARPA’s Airborne Launch Assist (ALASA) program. NOFBX™ is also in development for a flight experiment on the International Space Station.

Max Vozoff seems to have left ISPS in January 2014.

[docmordrid]

And this from June 2014

Just a short listing of NOFBX in an upper stage on pg 2,

Link.....(pdf)

Could be they've gone silent because of DoD/DARPA projects.

[cordwainer]

Yes and the other competitors are Energiya's atsetam based mixed-propellant and ADN(which is technically a hydrazine based propellant) their has also been some study put into hybrid organic propellants composed of literally oatmeal, and a turpentine/paraffin paste and nitrox with kerosene as a replacement for hydrazine. It looks like NASA will probably go with ADN if they can get it to work. Private space companies are likely to go kerosene/LOX or kerosene/nitrox. ESA might go with atsetam if things with Ukraine settle down. NOFBX doesn't offer much of an advantage over any of the other options I mentioned except maybe the hybrid propellant option. Since the process for making cheap ADN was developed in Germany the ESA might go with ADN as well, problem with ADN is it can be rather volatile. While technically more stable and denser than hydrazine which makes it less flammable it is also more explosive and burns hotter when it does burn, in other words when it does get going in really gets going. I'm partial to atsetam myself, we know it works and has been thoroughly tested and the Russians have shown it can be produced cheaply. Whether it is actually green enough to pass the EU's stringent protocols is debatable.

[savuporo]

Does anyone know what actually happened to NOFBx ?
The last relevant update is from here :
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20140010948.pdf

In  March  2011,  the  team  of  Innovative  Space Propulsion Systems and Firestar were selected to develop  and  perform  a  NOFBX  flight  experiment  at  the  International  Space  Station  (ISS)  in  late  2012.  Due  to  a  variety  of  factors,  the  ISS Program Control Board de-manifested the experiment from upcoming  missions and awaits further test data before putting it back on the manifest

Seems like Firestar Technologies isnt much of an active outfit anymore

[QuantumG]

Testing determined it wasn't as stable as they have claimed. There's better options (with lower isp).

[savuporo]

Yeah, the rumors, but it'd be interesting to know what the reports found.

http://www.usasymposium.com/craste/historical/2011/agenda.htm - 2011
Independent Assessment of Nitrous Oxide Fuel Blend (NOFB) Monopropellants Mr. Nickolas Demidovich (FAA AST-300) and Brian Brady (Aerospace Corporation)

http://www.aerospace.org/news/highlights/nofbx/

With NOFBX ready to ship to the International Space Station, the FAA hired Aerospace as a neutral third party to monitor final safety testing to make sure the tests met NATO standards.

ISPS conducted two tests, the drop and the fast cook-off. Drop testing involves dropping a container of the propellant from a height of at least 12 meters to observe its reaction upon impact. Ideally, the container should not explode. A fast cook-off simulates a shipboard fire to see how the propellant reacts to a rapid increase in heat. Monitors watch for sooty burn-off.

The FAA then hired Aerospace again to complete a secondary phase of testing to find a material from which to construct fuel tank valves.
“Some substances are not compatible with rocket fuel,” Brady said. “ISPS sent us two materials they thought might work. It was a good test. We found one that worked and one that didn’t.”

The one that failed expanded once exposed to the propellant and permanently sealed the valve.

Aerospace’s role with NOFBX is complete, for now. But Brady hopes Aerospace will be asked to work with NOFBX again.

“I think that if this will be flying to ISS, and potentially for the Air Force, there will be even more questions for us to answer,” Brady said. “There might be new challenges that hydrazine didn’t have.”

NASA Engineering and Safety Center, 2012
http://www.nasa.gov/pdf/732505main_TechUp_2012_pages.pdf

Comments speculation about connection to the now canned ALASA program :
http://behindtheblack.com/behind-the-black/points-of-information/changes-in-darpa-rocket-projects/


EDIT: Also is it just me, but it looks from the link like Brian B. Brady of Aerospace Corporation, Ph.D. in Chemistry just actually might be the Heisenberg ?

[Flometrics]

The NOFBX patent application number US12268266 was abandoned on 7-15-2015 after final rejection from the USPTO. Nitrous with a little bit of propane in it to help it decompose in a catalyst bed was tested at the University of Alabama Huntsville in 2000 before the patent was filed.  This idea resulted in patent US6779335B2.
Anyone who has read Clarke's "Ignition", is aware of the Scaled accident in 2007 or has seen race cars with nitrous explode would worry about this propellant mixture.

Steve

[Comga]

I don't get it.  Can someone explain what's happened?

Dr Harrington emphasizes what we know: Nitrous Oxide is unstable and dangerous.
Has ISPS/Firestar done anything to mitigate it?

The NOFBx system passed the NASA safety review.
It was always astounding that they would approve putting a big tank of this on the ISS.  How did ISPS do that?

ISPS's patent application was denied because of prior art at the University of Alabama Huntsville.
But what else is in the "X" of NOFBX besides "a little bit of propane"?
In fact their patent discusses "ethane, ethylene, and acetylene".

Aerospace performed independent testing, and found one material that was compatible and applicable for making tanks.
But they didn't say there weren't any compatible materials for tanks and valves.
In fact, the report is very upbeat, just before the whole thing vanishes.

ISPS conducted the 12 meter drop test. "Ideally, the container should not explode." 
Did it?
They did a fast cook-off test.  "Monitors watch for sooty burn-off"
Was any seen?

We have heard (citation not found) that ISPS had one of their 100 pounds-force (440 N) engines fail. 
(Something similar happened with Aerojet's large HAN thruster for GPIM.  That mission is flying with five small 1N engines instead of four of those and one 5 lb / 22 N center engine.  See this photo.)
Did ISPS get any engine to work for an extended period?

My personal half-educated opinion is that the major benefit of ISPS and NOFBX is that it got the Air Force and NASA off the dime to support GPIM, which is at least starting down the long road to an alternative to hydrazine.  It will be a long time until we can pull down from the web a dozen engine alternatives for HAN, but qualifying one is a start.  "The journey of a thousand miles begins with a single step."  But that's a separate subject.

[savuporo]

I don't get it.  Can someone explain what's happened?

Yeah, your post is what i was kinda asking about, not as eloquently. And, did it indeed go under DARPA ALASA somehow, and cause the explosions ? Stu Witt's public comment ( up thread ) is the only reference to that.

“The magic” in Boeing’s design, as DARPA officials described it, was the powerful nitrous oxide-acetylene propellant, also known as NA-7. The propellant would be “pre-mixed” to reduce the plumbing needed on the rocket, enabling it to carry more payload.

http://www.parabolicarc.com/2015/11/30/alasa-launches-hold-due-exploding-fuel/

[john smith 19]

The NOFBX patent application number US12268266 was abandoned on 7-15-2015 after final rejection from the USPTO. Nitrous with a little bit of propane in it to help it decompose in a catalyst bed was tested at the University of Alabama Huntsville in 2000 before the patent was filed.  This idea resulted in patent US6779335B2.
Anyone who has read Clarke's "Ignition", is aware of the Scaled accident in 2007 or has seen race cars with nitrous explode would worry about this propellant mixture.

Steve

Fair point.  I was never clear exactly what catalyst could do NO2 on its own.

I thought Flometrics had disappeared. Nice to see you're still around.  I recall you're positive displacement drinks dispenser very fondly.