Smoke only motors?

[stormbringergrey]

I am downsizing from HPR to MPR but I'm still a bit of a showoff and want to dump as much smoke as possible. My future builds will be limited to 24mm (mostly F44W/G65) but I have a penchant for clusters and pods where I could mount smoke only motors if such a thing exists.

 

[tsmith1315]

Motors must produce thrust to be motors. Otherwise, they are pyrotechnic effects.

 

[stormbringergrey]

Motors must produce thrust to be motors. Otherwise, they are pyrotechnic effects.

Accepting that, is there a specific prohibition against the use of a smoke generator?

 

[stormbringergrey]

Accepting that, is there a specific prohibition against the use of a smoke generator?

Just found this thread and bottom line is any flammable pyrotechnic is prohibited and most other approaches look impractical.

There is some discussion about plugging the nozzle of a C6-0, mounting it upside down, and igniting from the open end. Not sure I'd try that on any labor intensive build.

https://www.rocketryforum.com/threads/thrustless-motor-smoke-generator.153155/

 

[CalebJ]

Other than the MRC FX motors from many years ago, I don't think it's really been done.

 

[Grog6]

Firefox used to sell smoke bomb kits; I wonder if it could be added to an engine similar to what estes uses? Do a 'smoke grain'?

 

[dhbarr]

A smokey tucked up inside a heat resistant tube should produce a significant plume without violating any rules of which I'm aware.

 

[rcktnut]

A spent Estes casing with an enlarged nozzle with a sugar rich Kno3 mix will do the trick. Lots of smoke.

 

[Steve Shannon]

By Newton’s 3rd, anything that ejects mass in one direction has a reaction in the opposite direction. The burning of a mixture and expulsion through a nozzle is a motor. Although the thrust is very low and takes a long time to be delivered it’s still either a motor or a pyrotechnic effect. In either instance the smoke will be hot as it’s ejected and possibly capable of starting a fire.
If it’s a motor it would need to be flown as a research motor. If it’s a pyrotechnic it’s prohibited from being flown at either Tripoli or NAR launches.
If you want fireworks that’s a different hobby.

 

[VTS SkunkWorks]

The RC airplane folks make smoke generators for RC planes with electric motors. Just one example.
https://www.motionrc.com/collections/smoke-systems

 

[manixFan]

There was a Saturn V flight at the 2008 LDRS in Argonia that used some small motors that were lit on the ground for smoke effects just before the actual launch. I don’t recall if they were part of the somewhat scale launch tower or on the rocket itself. But they started a grass fire that required the fire crew to put it out. One of those ‘it seemed like a good idea at the time’ plans.

Just a data point.


Tony

 

[rcktnut]

There was a Saturn V flight at the 2008 LDRS in Argonia that used some small motors that were lit on the ground for smoke effects just before the actual launch. I don’t recall if they were part of the somewhat scale launch tower or on the rocket itself. But they started a grass fire that required the fire crew to put it out. One of those ‘it seemed like a good idea at the time’ plans.

Just a data point.


Tony

I agree the safety code not allowing such items should of course be followed. In the case of a fire being started at the launch pad, it sounds as if the pad was not cleared of flammable debris to the extent that it should have been.

 

[cls]

one time, I put a string of about 10 pyrodex pellets on the ematch wire, coiled up in a round cookie tin, under the blast plate of an HPR cluster. burned for less than 4 seconds and the smoke dissipated quickly, but made the point. lit via separate circuit, coordinated with LCO.

 

[VTS SkunkWorks]

Back around 1997 Gary at Aerotech was making "Turbo" Hybrid motors that had a grain of White Lightning forward of the other (cardbard) fuel grain. With his OK and advice, I epoxied the insulating disk to aft the face of the WL grain and applied epoxy to the fwd face. This made the WL grain a "long burn" core burner with no grain faces burning. The goal was to provide tracking smoke for the otherwise smokeless hybrid motor and it would keep smoking after the N2O was used up. Flew it at Delmar as experimental, worked great. Didnt melt my casing and had great tracking smoke.

 

[K'Tesh]

One trick done for generating smoke is to take a motor (say a C6-0), install it backwards, and ensure it gets ignited as you would a cluster. However, instead of installing your igniter in the nozzle, you do it from the normal "top" of the motor (don't forget to scrape away part of any clay caps in motors with a normal ejection). This means that the grain will not burn in a confined space, and pressurization will not occur as normal. The grain just burns, generating smoke without much (if any) thrust.

 

[jhill9693]

Other than the MRC FX motors from many years ago, I don't think it's really been done.

I have about a half dozen packs of these, if anyone is interested I'd be willing to part with some of them. They are at least 20 years old, ymmv.

 

[mitchboese]

There was a Saturn V flight at the 2008 LDRS in Argonia that used some small motors that were lit on the ground for smoke effects just before the actual launch. I don’t recall if they were part of the somewhat scale launch tower or on the rocket itself. But they started a grass fire that required the fire crew to put it out. One of those ‘it seemed like a good idea at the time’ plans.

Just a data point.


Are you referring to this launch? My 1/35th scale Saturn 1b in 2003, Argonia. We had approval to ignite 4 low thrust 29 mm outboards with lined Thermaltake igniting the central K 550. Unfortunately took longer for the Thermaltake than anticipated. Torched the ground, charred the launchpad and tower but stayed intact.

⁷

 

[manixFan]

View attachment 596738⁷

Those are fantastic! Pretty much exactly as I remembered, but the tower seems bigger. Very cool that you have the sequence taken by Nadine.

Thanks for sharing those, that was a memorable LDRS on many levels.


Tony

 

[Cape Byron]

I've usually found that teenagers at the launch vaping gives me enough ambient smoke.

 

[mitchboese]

Those are fantastic! Pretty much exactly as I remembered, but the tower seems bigger. Very cool that you have the sequence taken by Nadine.

Thanks for sharing those, that was a memorable LDRS on many levels.


Tony

I remember yelling "live motor!" to the fire crew as they were running out there. She lit and launched when they were halfway. Dennis Blackburn fell and broke his collarbone. I felt really bad although I was relieved it wasn't worse.

 

[Absouloot]

What about using a powder and set it up like a sand blaster, where the rushing air passes over the opening with the power and draws it out. Probably not a LOT of smoke, but I am thinking it could create a trail. That way you get away from the pyrotechnics too! It might be a fun project to try, put it on the shock cord so it's being exposed to the most air movement on the way down? And it would seem that it would only be one tube to direct the air next to a capsule holding the power with a hole between the two. (hey.. if someone does this and it works.. you heard it here first!! )

After re-reading, you want the smoke to be on the launch? Hmmm.. my solution is more for keeping track on the way down for high flyers.

 

[shockie]

A spent Estes casing with an enlarged nozzle with a sugar rich Kno3 mix will do the trick. Lots of smoke.

wouldn't NFPA 1122 or 1127 consider that as pyrotechnics? the NFPA really doesn't want people using pyrotechnic payloads in their rockets because of the potential fire hazard. except for course, launching out in the middle of a desert. It's kinda ironic in the sense, that G. Harry Stine did everything he could do to get the NFPA to accept rocketry, which they did eventually ; and here we are now, prohibited by those same NFPA regulations from using pyrotechnic payloads in our rockets. The constructs that we have devised over the past decades are now constraining us.

 

[SolarYellow]

What about using a powder and set it up like a sand blaster, where the rushing air passes over the opening with the power and draws it out. Probably not a LOT of smoke, but I am thinking it could create a trail. That way you get away from the pyrotechnics too! It might be a fun project to try, put it on the shock cord so it's being exposed to the most air movement on the way down? And it would seem that it would only be one tube to direct the air next to a capsule holding the power with a hole between the two. (hey.. if someone does this and it works.. you heard it here first!! )

After re-reading, you want the smoke to be on the launch? Hmmm.. my solution is more for keeping track on the way down for high flyers.

You mean like a functional Nike Smoke?

 

[David_Stack]

What about using a powder and set it up like a sand blaster, where the rushing air passes over the opening with the power and draws it out. Probably not a LOT of smoke, but I am thinking it could create a trail. That way you get away from the pyrotechnics too! It might be a fun project to try, put it on the shock cord so it's being exposed to the most air movement on the way down? And it would seem that it would only be one tube to direct the air next to a capsule holding the power with a hole between the two. (hey.. if someone does this and it works.. you heard it here first!! )

After re-reading, you want the smoke to be on the launch? Hmmm.. my solution is more for keeping track on the way down for high flyers.

The pre-Centuri Nike Smoke as kitted under the Enerjet label has that feature (a functional tracking smoke dispensing system):

https://www.oldrocketplans.com/enerjet/enjKE-3/enjKE-3.htm

 

[cerving]

I have about a half dozen packs of these, if anyone is interested I'd be willing to part with some of them. They are at least 20 years old, ymmv.

Ooh... where are you located?

 

[rcktnut]

rcktnut said:
A spent Estes casing with an enlarged nozzle with a sugar rich Kno3 mix will do the trick. Lots of smoke.

wouldn't NFPA 1122 or 1127 consider that as pyrotechnics? the NFPA really doesn't want people using pyrotechnic payloads in their rockets because of the potential fire hazard. except for course, launching out in the middle of a desert. It's kinda ironic in the sense, that G. Harry Stine did everything he could do to get the NFPA to accept rocketry, which they did eventually ; and here we are now, prohibited by those same NFPA regulations from using pyrotechnic payloads in our rockets. The constructs that we have devised over the past decades are now constraining us.

I don't know, but even if permitted a rocket containing them would have to be flown under research anyway. Many years ago my friends and I used to fill spent casings with melted Kno3 sugar for smoke bombs. The wording under the safety codes is payloads. Is one of these in a motor mount considered a payload? I always considered the safety code as not permitting a pyro device (50 grams of BP, mortar round, pack of firecrackers,) etc. to be carried up by a rocket and detonated in the air. In other words using a model rocket as a carrier for such devices. I don't see any harm in a smoke generator in a motor mount as long as it is well "out" by time the rocket hits the ground.

 

[Absouloot]

The pre-Centuri Nike Smoke as kitted under the Enerjet label has that feature (a functional tracking smoke dispensing system):

https://www.oldrocketplans.com/enerjet/enjKE-3/enjKE-3.htm

WOW!!! What a great idea! Has anyone tried this? Did it work? and how long did it "smoke"?
I wasn't thinking of dispensing throughout the launch process, which seems overkill because you already have the motor smoke. My idea was deploy with the parachute so you can track it on the way down.
Now you have me thinking on this way too much! I may have to try and build something and maybe find that power that people use in the color parades.
Found it (thanks Amazon)... Hmmm.. now the deployment piece? Oh, what about using a chute release and burrito a pouch of powder or just burrito some powder into the chute with the release!
I watched a twin Estes So Long launch video by ModelRockets321 go bye-bye! Very sad! Maybe there is a solution here, but I am sure I am NOT the first one to think this.

 

[jadebox]

As far as smoke at launch, just put some dry ice under the rocket and rig up some way to dump water on it as the motors are ignited.

On a more serious note, I have considered experimenting with putting dry ice in a Saturn V to simulate the fog and condensation that formed on and around it as it sat on the launch pad.

 

[ksaves2]

Shoot what goes round, goes round. Asked this question over 20 years ago and the answer is the same. The certifying entities won't allow it. Perhaps at a Tripoli launch where Research loads are allowed and being flown. If you tell the Tripoli LCO and explain your system, probably won't bat an eye. But of course one would have to be a member of Tripoli. Also a prefecture might just have "commercial" only launches depending on the venue. That's their right to do so, so best to contact someone in advance controlling the launch and ask first. N.A.R.? It's not allowed period unless flying smoke devices rule has changed over the years.

 

[prfesser]

rcktnut said:
A spent Estes casing with an enlarged nozzle with a sugar rich Kno3 mix will do the trick. Lots of smoke.


I don't know, but even if permitted a rocket containing them would have to be flown under research anyway. Many years ago my friends and I used to fill spent casings with melted Kno3 sugar for smoke bombs. The wording under the safety codes is payloads. Is one of these in a motor mount considered a payload? I always considered the safety code as not permitting a pyro device (50 grams of BP, mortar round, pack of firecrackers,) etc. to be carried up by a rocket and detonated in the air. In other words using a model rocket as a carrier for such devices. I don't see any harm in a smoke generator in a motor mount as long as it is well "out" by time the rocket hits the ground.

Opinion only: This is a very valid point. "Payload" has a specific meaning in hobby rocketry, and a motor that produces trivial thrust doesn't sound like a payload to me. As others have noted it would have to be a research flight, though.