Hybrids 2021

[maddmaxx11]

That is cool. Will it fit the 29mm SkyRipper motors?

 

[kramer714]

That is cool. Will it fit the 29mm SkyRipper motors?

I would think it could be used on a skyripper 29. I m not sure what the 'forward closeout' looks like on skyripper but if it like the 54 there is a smaller diameter cap that comes out of the top.

The way I designed this, the 3d printed adapter in blue fits over the top of the motor and the cap on the motor fits into the hole in the top (pictures show the adapter before it is bonded together.

Three things get bonded to the adapter. A 38mm coupler (red, smaller diameter longer fiberglass piece), a 38mm switch band (I didn't want the top of the rocket indexing on the PETG, this way it indexes on fiberglass), and a flat fiberglass washer that gets bonded into the coupler (again this way the loads from the rocket go through fiberglass not petg). The recesses in the adapter are to create a mechanical adhesive lock, not just counting on the adhesive bond. Yes i do now how to get a pure bond to PETG, but why not make it easier plus this way i dont worry about wiping off all the adhesive over such a long length.

The last step is to drill a hole through the adapter, coupler and switchband for the vent hose.

 

[NCTex]

Once you get the 'hang of things' hybrids like the Contrail are pretty easy to launch. The advantages to the prefilled have more to do with the GSE, but per the comments, the 'prefilled' are filled on site, not at home.

Anyone from So Cal that is interested in Hybrids, happy to show you how or have you use my GSE at one of the ROC launches.

I've been very interested in starting out in hybrids. Will you be flying any hybrids at ROCStock next Saturday? If so, I'd love to watch first hand how to launch these. I've been considering investing in Contrail rockets/GSE.

 

[Rocketbuilder]

They call it a liquid engine but it's a copied rattworks tribrid.

Well, not really. It was certainly heavily inspired by the Rattworks tribrid, especially the concentric tank configuration and piston to pressurize the fuel. But I would like to respectfully disagree that it is a copy.

The major differences are that it does not use a U/C valve or melt-away alcohol plug, and that the liquid fuel is injected from the moment of startup, so there isn't a "hybrid phase" of the burn. The flow of both propellants is initiated simultaneously by a pair of pyrotechnic valves located above the combustion chamber. This also means it doesn't fill through the injector, allowing for better atomization.

There was a very thin (approx. 0.020") layer of 3D printed PLA on the inside of the ablative combustion chamber liner left over from the casting process, so one could maybe consider the first fraction of a second to be running in "tribrid mode." However the ablative liner itself does not measurably contribute to the motor's thrust or total impulse.

As Neutron95 mentioned, we did perform additional static tests following the changes made after the April launch attempt, and we had two successful flights in the same day on August 21st of this year.

Because the valves only require an ignition signal to open and the fuel is pre-loaded before putting the rocket on the pad, the operational complexity is pretty much exactly on par with a typical Contrail hybrid, and arguably even simpler than the Hypertek system. All we need to do is fill the nitrous tank, then send the ignition signal to the igniter in the combustion chamber, followed immediately by the pyrotechnic valves.

I'd encourage you to check out our website if you're interested in learning more about our design approach. You can read about that motor as well as the others we're working on by following the links on this page.

It's unfortunate that Tripoli's leadership has such a vehement hatred toward bipropellant rockets, when they have the potential to be as safe and simple to launch as hybrids. Their fears seem to come primarily from a lack of familiarity and understanding, but with access to FAR their opinion is of little consequence.

 

[Joe Scuti]

Thank you Rocketbuilder

 

[DRAGON64]

So, before this thread and year ends, and before the 2022 year and new thread begins, I thought maybe some of you might want to share your hybrid rocketry year in review; I was watching some hybrid rocket motor and rocket launch videos, preferably those in the last year or so, and what should appear, but a slew of Contrail videos. Yes, the only hybrid motor mfg we have left is still creating innovative ways to improve the hybrid propulsion. As of this writing, there are a multitude of new videos on their youtube channel showing their work on injectors. Some of these videos are a mere couple hours old.

I received an email from Contrail last month asking for any launch videos, or anything related to their products that I have purchased from them. The email sparked me back into action to get my project off the ground:

• Finish the Super DX3 rocket build
• Get hybrid source tank re-tested and filled
• Maybe buy a spare tank
• Finish launch pad
• etc
• etc

As I mentioned some time back, I have the Contrail 98mm motor system, and currently only one load, the M1575.

So what are your reviews and plans for this and the next? If you are research oriented, state as much, and then link us to the research topic in the appropriate forum etc.

Before I close out, I was approached last month by a friend who is wanting to claw his way back into hybrid rocketry. To help him on his journey, I gave him a 10lbs supply tank, which I hope will work out for him. He too, is a big part of the spark lit under my but to get'n busy get'n busy with it... THANK YOU! I hope we can fly together sooner, rather than later.

 

[drewnickel]

Lots of stuff going on with Contrail. Will let Tom elaborate if he wants to, but suffice it to say the next couple years are going to be exciting for hybrid fliers.

 

[DRAGON64]

Agreed, it is time!

 

[Ez2cDave]

Following the victory in the lawsuit against the BATFE, Hybrid rocketry went into a "death spiral". Only time will tell if sufficient interest remains for the remaining manufacturer(s) to survive. I, for one, will not be returning to flying hybrids, as my only motivation was to the skirt the BATFE regulations. Enjoy and fly high !

 

[Voyager1]

Agreed, it is time!

Indeed!

2022 HPR season can't come soon enough! Thanks to Brad and Dan, I've a brand new WilsonFX hybrid launch control system to range test.

Clear skies and p'off COVID!

 

[DabCat]

Thanks to Brad and Dan, I've a brand new WilsonFX hybrid launch control system to range test.

Did you have to contact them directly to get one? When I tried to find their website all I got was a dead domain.

 

[Voyager1]

Did you have to contact them directly to get one? When I tried to find their website all I got was a dead domain.

Yes, contact them directly. See Post 52 in the thread https://www.rocketryforum.com/threa...-launch-controller.163797/page-2#post-2218696.

 

[Neutronium95]

I'm really looking forward to getting into hybrids whenever the new Contrail 54mm motors get certified.

 

[DRAGON64]

New thread has been posted: https://www.rocketryforum.com/threads/hybrids-2022.170098/