Rattworks I80 Hybrid

I just got mine today. Anyone familiar with it?? I'm really curious how it's gonna work, if at all. It's really long and 29mm, so I modified my Aerotech Arcas to handle it. Also, the price is right, at about $8 for an I161W equivalent. I hope to fly it this weekend, so I'll post my results.

Sounds very cool.

MarkBrown and BrianBarney are a couple of our Hybrid folks here.

They might be able to answer your questions.

I am a fan of hybrid rocket engines, I have wanted to get the I80 motor, I even have a rocket designed and the parts for it, but have lots of projects on the waiting list

I have seen several fly, be sure to have the rocket light enough to handle it, and if your using a barometric altimiter, be sure that the rocket will go over the minimum arming altitude, or you will be picking up pieces of your rocket after the flight. Make sure to drill a hole through the side of your airframe into the motor tube for the vent hole, I forget where it is for the I80, The most difficult part of flying my hypertek rockets is lining up the vent spurr and getting that darn tube on it. on the rocket I designed for the I80, I have a long 38mm central mount with a long 29mm adaptor on it. this way I can easily line up the vent tube on the adaptor, and vent it to the bottom of the rocket. you also have the option of flying a 38mm composite motor or one of the newly certified propulsion polymers motors in it.

Could you post some info (and pics ) of your rocket that will take the motor?

good luck

-Brian Barney

heres how it works..... Its a little animation type thing on how the UC valve RATT hybrids work. https://www.hawkfeather.com/rockets/hybrid_tutorial.html

-Brian Barney

The rocket is a modified (stretched) Aerotech Arcas. The rocket was stretched to accept my RRC2 altimeter. The whole white upper-section is the bay, with apogee only deployment. The motor is so long, the coupler where the rocket used to seperate is now a second motor mount to keep the motor from interfering with the recovery system. I must say, the rocket WILL go past the 300' minimum altitude to arm the altimeter. Sims are calling for about 3500' with the 5 second burn, and will recover on a single 24" parachute. This is gonna be a great flight!!

Reminder to myself: ARM THE ALTIMETER!!!!

Here's your picture:

Sorry about the wait, I had picture trouble. Thanks to PGerringer for posting it on his site. Also, the rocket has not been painted yet, but will fly tomorrow at CTRA-NARCONN on the Hybrid motor, weather permitting. I hope to post some pics of the flights and other flights from the launch.

The pics can be found at:

https://www.cybergatetech.com/phpgraphy/index.php?dir=Rocketry/misc/dpatell

About the weight for the RATTworks 29mm Motors:

The I-90 designation is a little misleading... While that is indeed the "average thrust along the burn time", it is important to note that the motor thrust drops off like a cliff after 3 seconds, and sputters for the remaining 1.75 seconds of the burn.

The thrust curve shows a maximum thrust of 36lbs within the first .5 seconds of the burn, and it is sustained above 25lbs for 1.25 seconds.

At the most conservative, a 5lb rocket would fly nicely on this load. One could, I assume, launch up to a 7lb rocket in the right conditions (no wind, long rail, etc.) with this motor. Not that I would.

Todd Moore