Sugar powered rocket motors???

[mattitude]

Ok...I just finished watching "It's Effin' Science" and they did an experiment with sugar to launch a LPR and then a HPR. The first rocket motor was made with 6oz. of melted candy bar mixed with potassium nitrate and were able to launch their rocket 500 feet. Next was 2.5 pounds of pure sugar mixed with maple surup (to make the mixture a moldable solid) and then launched a HPR 6000 feet! Their last launch was with 10 pounds of sugar to see how high they could send a 200lb. porta potty in the air, but that was nothing more than a crash and burn. Is this possible??? I mean, sugar powered rockets would make this hobby much more affordable for me as a bag of sugar is much cheaper than HP rocket motors.

 

[troj]

Yep, people make sugar motors. Richard Nakka's website is considered one of the best on the topic.

Regarding sugar motors, some sugars are definitely safer than others. The reason why is that in some (sucrose, if I remember right, is one) the auto-ignition temperature is very close to the melting temperature, so it's very easy to have it flash up while being prepared. Others, such as dextrose, the two points are further apart, making it safer to prepare.

One thing you'll find is what most people have learned -- unless you make and fly a lot of motors, the investment required to make your own will exceed the cost of what you'd spend if you flew commercial motors. Making motors has a learning curve which will result in ruined hardware and ruined rockets.

In addition, NAR does not endorse making your own motors, and they cannot be flown at a NAR-sanctioned event. Tripoli does endorse making your own motors, and has rules regarding some material limitations, who can fly them, and what events they can be flown at.

-Kevin

(I've made a few APCP motors)

 

[1974_Trident]

Using sugar as a fuel is nothing new or bizarre. Sugar is just a lot of Carbon and Hydrogen with some oxygen thrown in ([CH2O]x).The Oxygen in the Sugar does not participate in the combustion because it is not free oxygen. The oxygen needed for combustion is liberated from the Potassium Nitrate (KNO3) when heated. Sugar and Potassium Nitrate have a fraction of the specific impulse of our beloved Ammonium Perchlorate/Aluminum propellants but will work. Think of the Sugar/Potassium nitrate as a diet propellant.

 

[mattitude]

Well...I did not know that! The wealth of information here is amazing and I learn something every time I poke around here a bit. I rarely fly now as it is (it's too hot to be outside for more than 20-30 minutes) so the investment wouldn't be worth it to me, so I'll just stay with my stockpile of disposable motors for now.

 

[gpoehlein]

Something else to consider - It can be relatively easy (and note I said RELATIVELY) to make a sugar motor that provides thrust. It is considerably harder to make one that has a reliable delay and ejection charge. Also, consider consistency - except for the occasional mishap, you pretty much expect an given Estes A8-3 to perform like any other. There might be a small variation, but not that much. Sugar motors, on the other hand, can vary widely in performance depending on how tightly they are packed, how consistent you are in forming the nozzle and how smooth the mixture is. (Note that I speak here not from experience but from having read as much as possible about the process. Knowing what I do about chemistry and physics, I know that human loaded motors are not going to be as consistent as machine loaded motors.)

 

[JAllen]

Also, one should mention that KNO3 is still on the BATFE Federal Explosives list and as such ALL sugar propellants using KNO3 fall under jurisdiction of the BATFE and the rules in the Safe Explosives Act. Basically, you can make and transport off your property your own APCP motors, but not a sugar motor without a BATFE license.

 

[billspad]

I was half awake when I watched the show. Did I hear correctly that they used maple syrup as a binder?

 

[mattitude]

Yep. I still have it on my DVR because it was hard enough watching/hearing it with a 1 month old being cranky.

I was half awake when I watched the show. Did I hear correctly that they used maple syrup as a binder?

 

[judo]

Jimmy Yawn has a site as well. He's even built a motor using Pixie Stix, with a rocket by the same name. Poke around on NEFAR's site; he has a few launch video's there.

 

[Handeman]

Also, one should mention that KNO3 is still on the BATFE Federal Explosives list and as such ALL sugar propellants using KNO3 fall under jurisdiction of the BATFE and the rules in the Safe Explosives Act. Basically, you can make and transport off your property your own APCP motors, but not a sugar motor without a BATFE license.

Are you sure about that? Potassium nitrate is not a regulated substance in and of itself. You can buy it at most drug stores. The BATFE list of explosives lists potassium nitrate explosive mixtures as being regulated. The law suit proved that APCP propellant was not an explosive. I would contend that KNO3 propellants would fall in the same category and also be unregulated since they wouldn't be "explosive mixtures".

 

[rocket999]

Are you sure about that? Potassium nitrate is not a regulated substance in and of itself. You can buy it at most drug stores. The BATFE list of explosives lists potassium nitrate explosive mixtures as being regulated. The law suit proved that APCP propellant was not an explosive. I would contend that KNO3 propellants would fall in the same category and also be unregulated since they wouldn't be "explosive mixtures".

That is what I thought, but I was corrected. The ATF did a lot of tests on kno3 mixtures, and they couldn't get it to do anything but burn, but the still regulate it for some reason. This was discussed at length on rocketry planet awhile ago.



I think it's dumb too.

Sam

 

[Handeman]

Sounds like the regulate it for the same reason they used to regulate APCP. It also sounds like they did enough research on their own to prove that.

I still think they would have a hard time proving you were violating any laws if they can't prove KNO3 propellants are explosive since the list does say "explosive mixtures". Not sure I would want to be the test case though.

 

[bobkrech]

Sounds like the regulate it for the same reason they used to regulate APCP. It also sounds like they did enough research on their own to prove that.

I still think they would have a hard time proving you were violating any laws if they can't prove KNO3 propellants are explosive since the list does say "explosive mixtures". Not sure I would want to be the test case though.

It really doesn't matter what anyone thinks. It's on the Explosives list.

Unless you have $800K and 10 years to prove in court it doesn't belong there, you should have a BATFE license to CYA.

Bob

 

[troj]

It really doesn't matter what anyone thinks. It's on the Explosives list.

Unless you have $800K and 10 years to prove in court it doesn't belong there, you should have a BATFE license to CYA.

I suspect subsequent items that are contested will get removed more easily, as precedent has now been set.

That said, it still won't be cheap, quick, or easy.

-Kevin

 

[MarkII]

I'd like that to be true, but I'd be afraid that they would dig their heels in further, to prevent further attenuation of the list.

 

[cjl]

I'd like that to be true, but I'd be afraid that they would dig their heels in further, to prevent further attenuation of the list.

That may be the case, but there is a legal precedent set, and if a judge decides otherwise, there's not much the BATFE can do.

Of course, that would involve taking it to court, which is never a cheap or easy proposition.

 

[UPscaler]

not quite explosive but it buns quickly

 

[troj]

I'd like that to be true, but I'd be afraid that they would dig their heels in further, to prevent further attenuation of the list.

They can dig them in all they want, but unless they get a different judge to toss the precedent that's been set not only by the US District Court, but also by the Appellate Court, that would be very difficult for them to do.

-Kevin

 

[Jeffery Brown]

Also, one should mention that KNO3 is still on the BATFE Federal Explosives list and as such ALL sugar propellants using KNO3 fall under jurisdiction of the BATFE and the rules in the Safe Explosives Act. Basically, you can make and transport off your property your own APCP motors, but not a sugar motor without a BATFE license.

Now THAT is a good piece of information to have if one wanted to know how to STAY OUT of prison

 

[shockie]

Are you sure about that? Potassium nitrate is not a regulated substance in and of itself. You can buy it at most drug stores. The BATFE list of explosives lists potassium nitrate explosive mixtures as being regulated. The law suit proved that APCP propellant was not an explosive. I would contend that KNO3 propellants would fall in the same category and also be unregulated since they wouldn't be "explosive mixtures".

Tell that to the BATFE as they lead you away in handcuffs for possession of explosives.

Although the FBI about 10 years ago arrested 2 Arab guys and charged them with possession of explosives for having and transporting a few sugar propellant rocket motors.

They tested the rocket motors and of course they didn't explode; so they dropped the charges and convicted them of something completely different.

Jimmy Yawn was a witness for the defense.

I used to have a copy of the FBI test report but lost it somewhere in time.

 

[prfesser]

Thread is alive after 13 years!

True, potassium nitrate itself is not on BATFE's list, else one would have some small difficulty buying it from garden stores, Walmart, wherever.

<lecture mode on>
KNO3 is a compound; always has the same composition and same chemical and (many) physical properties, whether it's made in a lab, obtained from human waste, or dug out of the ground. Add something else---anything else---and you have a mixture, with properties that depend on what, how much, and how the something else is added.

"Potassium nitrate exp***ive mixtures" is essentially a way for powers-that-be to deem ANY mixture they choose, that contains KNO3, as an exp***ive. After all, if it's an exp***ive mixture it doesn't matter one whit what's actually in it. Adding the words "potassium nitrate" makes enforcement easier.

Regardless, KNO3 plus sugar, sorbitol, what-have-you falls into that category; it's on the list.

Now, the odds are pretty good that TRA members who fly sugar motors at TRA launches are in no real danger of being arrested. After all the motors are in fact motors, and that they are being flown in a proper venue with FAA permission and all. A crackdown would have little upside for powers-in-charge and might create a public relations nightmare. Nonetheless, if a government employee wished to make an example, s/he could indeed arrest someone for such an infraction.

 

[Rschub]

One of the reasons I am working to level 2 is the for opportunity to work with sugar-based motors, this puts a bit of a damper on my enthusiasm.

Thanks for the info.

 

[Handeman]

"Potassium nitrate exp***ive mixtures" is essentially a way for powers-that-be to deem ANY mixture they choose, that contains KNO3, as an exp***ive. After all, if it's an exp***ive mixture it doesn't matter one whit what's actually in it. Adding the words "potassium nitrate" makes enforcement easier.

Regardless, KNO3 plus sugar, sorbitol, what-have-you falls into that category; it's on the list.

I don't believe that is the case any longer. Part of the 2000 law suit that took APCP off the low explosives list was that BATFE was required to define what a low explosives was. They did that and then found out APCP didn't meet their new definition which I believe is why the judge vacated APCP from the list.

So when they say something is a "Potassium nitrate exp***ive mixtures", it not only has to have Potassium nitrate in the mix, it also has to meet the BATFE definition of explosive that they defined and put on record during the law suit. Since sugar propellants have a slower burn rate than APCP, I don't believe it can ever be proven to be an explosive.

Unfortunately, until it actually gets in a court and there is a ruling, they can still call sugar propellants anything they want.

 

[prfesser]

I don't believe that is the case any longer. Part of the 2000 law suit that took APCP off the low explosives list was that BATFE was required to define what a low explosives was. They did that and then found out APCP didn't meet their new definition which I believe is why the judge vacated APCP from the list.

So when they say something is a "Potassium nitrate exp***ive mixtures", it not only has to have Potassium nitrate in the mix, it also has to meet the BATFE definition of explosive that they defined and put on record during the law suit. Since sugar propellants have a slower burn rate than APCP, I don't believe it can ever be proven to be an explosive.

Unfortunately, until it actually gets in a court and there is a ruling, they can still call sugar propellants anything they want.

Your last sentence is, likewise unfortunately, the operative one in reality.

I'm pretty familiar with the lawsuit. Frankly, in some ways I'd rather not have been, but ya do what ya gotta do.

Also reality vs. government entity: individual P arrested for sugar motor. P says no, you gotta prove it's exp***ive. GE: Nope, sez right here, in our list, you made an exp***ive. Court: Guilty. P: I'll appeal and sue. GE: Bring it. We can afford a lot more lawyers than you can.

I know, it's simplistic, but it will end badly.

 

[Rschub]

Yeah, this just sounds like something that will hasten my sudden but inevitable conflict with the feds.

 

[Charles_McG]

It's well established in the alcohol biz that if you and the TTB (successor agency to BATFE in Treasury) have a difference of interpretation of the law or regulations implementing law, you settle it in court. That's the way it works - there's isn't an internal mechanism for re-interpretation.

It's true of the States too, as far as I can tell.

 

[Steve Shannon]

I'm pretty familiar with the lawsuit.

Your modesty and gift for understatement are priceless!

 

[Rschub]

Well, just looked at the list, Black powder and Black powder substitutes are also on there.

https://www.govinfo.gov/content/pkg/FR-2021-12-23/pdf/2021-27852.pdf
Back to knitting I guess.

 

[Steve Shannon]

Well, just looked at the list, Black powder and Black powder substitutes are also on there.

https://www.govinfo.gov/content/pkg/FR-2021-12-23/pdf/2021-27852.pdf
Back to knitting I guess.

They have been for years.

 

[tsmith1315]

Well, just looked at the list, Black powder and Black powder substitutes are also on there.

With an exception for BP arms.



It’s a flintlock, see. I have to use 4f in the pan.