Hybrids 2017

The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

DRAGON64

Well-Known Member
TRF Supporter
Joined
Jan 17, 2009
Messages
5,209
Reaction score
2,751
Location
Toney, AL
Previous Threads:

Hybrids 2015
Hybrids 2016

Another flying season gone-by, and a new one is just ramping up... what are your goals for flying hybrids during the 2017 flying season? Anything and everything hybrid related is welcome!

* Motors
* Vehicles
* Ground Support (GSE)
* Research motors discussion (within the limits of a non-research forum)
* Electronics
*Altimeters; Vent sensors; GPS etc etc
* Commercial/Professional advancement hybrid discussion
* College development (i.e. Stanford etc etc)
* Events/Launch coverage
* New flyer questions
 
I know nothing but want to fly one by the end of the year.
 
Hybrids sound like fun, but I need to learn the basics before I even consider flying them in the future.
It sounds pretty complicated. I'd love to see one launch though!

How about that though?
In 2017 I want to learn as much as I can about hybrid motors and see one fly!
 
I want to finally get my [new] K240 and K350 Tribrid in the air. My only real holdup is I don't have a rocket with a 66mm or larger motor mount.
 
I would so like to fly a Tribrid!

I hope to be flying my normal amount but life will tell... Going to maybe do some smaller 38mm Contrail. Been a while since I've flown smaller motors. Thinking a J800 maybe. LOL! Normal would be a 54mm 3 motor cluster Very cool on 3 J416 sparkies and I may do the two stage again. It's a 75mm to 54mm. Throw a couple of HyperTEK in the mix and I'll be a happy camper for flights in! :)

Jason

I want to finally get my [new] K240 and K350 Tribrid in the air. My only real holdup is I don't have a rocket with a 66mm or larger motor mount.
 
I've been having a hard time figuring out which hybrid system producers are still in business. Any listing of currently active producers?
 
While we're here: I'm looking for details on the various NOS injector arrangements used by these in their 54mm jobbers to compare with AT.

I haven't stumbled across a thread ( or even a dead link ) discussing same. Thoughts on where to go? New thread asking folks to dust them off and measure?

Edit: stop being lazy, DH!

New question: is AT the only certed load to ever have a plate injector?
 
Last edited:
While we're here: I'm looking for details on the various NOS injector arrangements used by these in their 54mm jobbers to compare with AT.

I haven't stumbled across a thread ( or even a dead link ) discussing same. Thoughts on where to go? New thread asking folks to dust them off and measure?

Edit: stop being lazy, DH!

New question: is AT the only certed load to ever have a plate injector?

I did my L3 using a Contrail motor as a promotion by Contrail at LDRS 24, and I thought it had one with the nylon nitrous tube woven in and out through the various injector ports. I could be wrong; that was a while ago and I wasn't very aware of injectors at the time.
Hypertek simply has a central hole that the fuel spigot slips into. I still have a Hypertek M motor and two reloads.
 
Last edited:
I have flown AT 54 with the plate and removable screws to vary flow and a friend really likes to fly the 98s.
I have flown Hypertek, once and as stated it has the drop spigot but I thought there was some way to adjust the injector in bell housing depending on motor choice.
The mono tubes just had the plastic fill line run up to the injector that burnt off with the igniter. I know there are many folks way more knowledgeable that me on this forum..
 
I have flown AT 54 with the plate and removable screws to vary flow and a friend really likes to fly the 98s.
I have flown Hypertek, once and as stated it has the drop spigot but I thought there was some way to adjust the injector in bell housing depending on motor choice.
The mono tubes just had the plastic fill line run up to the injector that burnt off with the igniter. I know there are many folks way more knowledgeable that me on this forum..

It looks like the plate injector is literally just a stainless plate with qty. 4x 3-48 tapped holes, which surprised me. I believe I should have a fairly complete one headed my way, and will take detailed shots when it arrives.
 
Hybrids have been on my bucket list a long time, but I don't think there is anyone flying them near me anymore. I fly at MDRA these days and they don't even plan to have GSE at LDRS, so I think I need to look to farther away launches if I want to learn from someone in person. What east coast launches typically have folks flying hybrid these days?
 
That's one of the reasons I'm pursuing AT: DOT 3AL 10oz nitrous cylinders I can have prefilled at the performance shop.
 
GSE can add some costs. For monotubes, it's not that complicated though. You need 1 solenoid valve, a tank, and some flex tubing. Consumables like compression sleeves.

A vent sensor is really nice to have, as is a dump valve. A normal club launch controller can trigger the valves just like an ignitor. Hold the fill on until it vents, hit fire.
 
GSE can add some costs. For monotubes, it's not that complicated though. You need 1 solenoid valve, a tank, and some flex tubing. Consumables like compression sleeves.

A vent sensor is really nice to have, as is a dump valve. A normal club launch controller can trigger the valves just like an ignitor. Hold the fill on until it vents, hit fire.

I always saw setups where there was radio to the guys operating the GSE and it was a completely separate system. That was years ago. You make it sound downright easy...
 
I always saw setups where there was radio to the guys operating the GSE and it was a completely separate system. That was years ago. You make it sound downright easy...

I wouldn't go so far as to say it's easy, but it's doable without going real nuts.

The solenoid valves have 2 wires. Connect those to the clips on a 12V launch controller. That will trigger them fine. Oh, make sure you buy 12V solenoids! :) I don't know if they are still selling them, but the website is still up. I bought mine here: https://pratt-hobbies.com/products.asp?cat=15

They are listed out of stock, but it shows you what to look for. I got the BFV for filling, the enono for dump, then built my own manifold. It's really just some plumbing fittings. I got the tank, hoses, fittings, and gauge from local places. You can probably get the valves cheaper elsewhere, but you do need to make sure they are oxygen safe. You might try car speed shops, they work with N2O all the time..

Some people build their own controller and such as well. I did that and it works well. But you don't have to. You do need to make sure that if you use a club setup you know for sure which channels do what. You wouldn't want to have it fire when you want to dump, for example. :)

I've been working on my GSE... I really need to finish it up and maybe post some info about it.
 
What east coast launches typically have folks flying hybrid these days?

Hybrids are flown at MARS launches (Geneseo) occasionally and I have a 3 cluster Contrail K planned for URRG (Potter, NY) if I finish the project in time. If in time, I may bring to LDRS this year.
 
tvin_autom_ball_valves_O_F.jpg

A few years ago have been designed the RC liquid fuel worm pump and a two-channel servovalves. In a design of the valves 2.2 kg microserves (2) and Swagelok ball valves are used. Both devices are intended for tripropellent hybrid rocket motor Me_HL_1000. Additive information is available for all comers.
 
The radio is kind of a pain, what works well is SIMPLE hand signals.

For years now, my son operates the GSE and I'm near the pad looking for a fill. Our simple hand signals are;

1) Pump, a straight hand 'pumping up and down', he hits the fill for one second. I then go out to the rocket, look listen, feel for leaks, does everything seem right?. This is a good time to see if there is nitrous coming from the nozzle (their shouldn't be), is there gas coming from the vent (there should be), are there any 'leak noises coming from the tank or fill hoses.
2) Hold, arms crossed above my head, stop filling, don't dump but stop filling. This is useful if something doesn't seem right, or if you are not sure if the tank is filled, plus if there is a range concern that you want to make sure is clear (someone went out on the range, aircraft sighted etc) .
3) Fill, straight arm going in a circle, fill until you see some other command
4) Dump, 'hand 'cutting' across my neck, dump, and abort
5) Fire', hand above head thumbs up, plus me moving farther from the rocket, 10 second count as long as my hand stays up, hand down hold.

These commands are easy to see from 1,000 feet (the longest one of my cables), and each one is clearly different than the others, simple and has worked well.

He has 'passed gas' for some other people, they use the same hand signals.

As far as making your own GSE, not too hard but my suggestions are,

A) Use a solenoid saver, funny thing this is most important for the vent. During fill the solenoid actually gets cooled by the nitrous, during vent, if you hold the vent open too long you can fry the solenoid. I use simple capacitor / resistor.
B) Use good hardware (and buy extras), pressure rated stuff from McMaster dont use the home depot stuff.
c) Think it through before you start assembling stuff, sounds simple but things like how much clearance do you need to get a wrench on the tank with the valve guard in place can make a difference.
D) have the vent point down, not to the side.
e) For hoses, get a long hose AND a short hose and connect them together, the hose closest to the motor gets beat up pretty bad, not just from exhaust but from the hose whipping after launch. Change out the short hose (cheep) and keep the long hose (not cheep) in better shape. Plus then the long hose acts like a spare if the short hose gets damaged.
F) buy a wrench, really, buy the right size wrench (1 1/8 for my setup) not an adjustable wrench but the real one you need. makes it easy to put the valve on and off, without leaks or rounding off the flats.

Lots of ways of doing this, just wanted to share a simple way of doing things.

Mike K

P.S. I plan to launch more this year than last year at Lucerne, im not there every month, msg me if you want to use my GSE at the launch.

P.P.S. Nitrous is going to be a bit harder to get this year one of the larger plants is down for a while https://nypost.com/2016/12/16/fatal-explosion-leads-to-whipped-cream-shortages-across-country/
 
Last edited:
Number 1 : Complete my GSE support cart for my Hypertek.

  • Wireless communication
  • Live video feed from the pad
  • Load cell under the tank to monitor the fill
  • Temperature sensor at the vent port to detect Nitrous venting
  • Convection cooling for the Nitrous Tank (I fly in South Carolina so Nitrous Tank temps get dicey in the July and August)
  • Pile all this on a custom cart so I can back the trailer up to the pad area and roll out GSE.
  • Mount a rail system on the cart to handle 54mm Motors.
  • L & M Motors will use a separate pad deployed next to the cart.

Number 2

Repair the Gas Passer after the crash last May caused by a low fill (hence the new GSE)..... Have the replacement airframe and nosecone (just need the time)


Number 3

New 5" Fiberglass project for both L and M Hypertek motors (Just need the time)

-Sam
 
I want to test my 3-inch N motor before the second flight this summer. I also have 2 other 3-inch M motors that I want to test. Trouble this time of year is the weather. Last week it was -17 here, hybrids don't like that much.

I've actually been doing more research solids lately. My son has a rocket that flies great on a 3 grain 38mm and we are building one that will fly on a 3 grain 75mm. For the sport flying these are a bit less hassle to fly a couple times in a day.

I've also made a new jig to cut snap rings into cases with a router. I have two five inch cases that I want to put snap rings in.

Edward
 
One of the IREC teams from Montreal posted this video. Thought you guys might enjoy!

[video=youtube;8ZTkx7DpUFA]https://www.youtube.com/watch?v=8ZTkx7DpUFA&t=8s[/video]
 
I made a jig where the case rests on four different wheels and can be rotated. It has a strap that goes around it to keep everything from moving. The router is fixed on one end and can move in an arc controlled by a scissors lift type thing.

The router also has a keyseat cutter in it.

You strap down the case and push against the stop. Then you lower the router 0.005" into the casing and then slowly rotate the casing around. Repeat until you have the depth you want for the groove.

It typically is a two person operation. For larger cases it might take 5 minutes per end to put a groove in it. You just have to make sure you true up the tube end before you start.

Edward
 
Number 1 : Complete my GSE support cart for my Hypertek.

  • Wireless communication
  • Live video feed from the pad
  • Load cell under the tank to monitor the fill
  • Temperature sensor at the vent port to detect Nitrous venting
  • Convection cooling for the Nitrous Tank (I fly in South Carolina so Nitrous Tank temps get dicey in the July and August)
  • Pile all this on a custom cart so I can back the trailer up to the pad area and roll out GSE.
  • Mount a rail system on the cart to handle 54mm Motors.
  • L & M Motors will use a separate pad deployed next to the cart.

Number 2

Repair the Gas Passer after the crash last May caused by a low fill (hence the new GSE)..... Have the replacement airframe and nosecone (just need the time)


Number 3

New 5" Fiberglass project for both L and M Hypertek motors (Just need the time)

-Sam

I can help you with your GSE should you need it. I have stand alone vent sensors or vent sensors that you can integrate into your GSE as I have done.

Also, for "convection cooling" I place my tank in a 5 gallon bucket with water and drench a towel which is wrapped over the tank. The evaporative cooling is quite effective.
 
I have seen a couple of IREC teams try to implement a load cell for the rocket. Both have had pad issues that prevented their use, mainly due to lack of testing and mounting complications. I would suggest that instead of a load cell use a pressure transducer with a piston of a fixed area to translate weight to pressure. Additionally, you can have a 4" gauge at the pad that you can read remotely. When you put your rocket on the pad dry you can mark that pressure. Then calculate what full weight is and make an additional mark on the gauge. Then you have a set point that you are aiming for. This would be a backup to an electronic pressure transducer.

Edward
 
That's interesting. I considered trying to mount a load cell under the rocket to determine if it was full. I decided I was more likely to damage the cell that way, and considered putting the N2O bottle on one instead, but that doesn't account for loss in the lines... Something like the piston might be a good compromise. I've had decent luck with vent sensors, but thought it might be nice to have a backup if nothing else. And with weight you know how full the tank is, no guessing based on temperature etc.. It would be interesting data to have, particularly if you're doing research hybrids.
 
Back
Top