2 Leviathan kit bash, boosted Leviathan?

A boosted Leviathan? It's been done. But I don't know that it's been done in this manner. ORK file attached. Thoughts?



View attachment Boosted Leviathan.ork

Go for it I do suggest you make the booster longer as you will need to use electronics to ignite the second stage.

Not necessarily. It is actually preferable by some to put the firing circuit for the sustainer in the upper stage.

H_Rocket said:

Not necessarily. It is actually preferable by some to put the firing circuit for the sustainer in the upper stage.

Click to expand...

No, I know however I don't think your going to want to do tumble recovery and you need room for a chute. Now that I think about it I don't see why tumble recovery won't work as it's a light rocket. I still say go for it. 2-Stage rockets are great!

+1 on sustainer start electronics in upper stage since I gather it will be using composite motors.

I really like how your configuration looks. The short booster makes it look like an upscale LP rocket which is more aesthetic imho, than HP staged rockets with the longer booster.

Another consideration is stage separation. Using the sustainer start gases to separate stages can toast your booster. Maybe a loose stage coupling so drag separation occurs at booster burnout is a simple option. If the sustainer is started with the stages still coupled you will want some vent holes in the coupler so the composite motor lights properly.

What are the booster motor options? It looks like the booster is tumble recovered. With a short booster you are limited to shorter motors. For the booster, I like higher average thrust and at least as much total impulse as the sustainer motor. That will keep the flight more vertical. Also, you will want electronic recovery deployment in the upper stage in case the sustainer does not light.

Lots of things to think about. Looks like a really interesting project.

conman13 said:

Go for it I do suggest you make the booster longer as you will need to use electronics to ignite the second stage.

Click to expand...

+1 for longer booster.
Here's what I'm planning for the summer:

I'ts just another estes tube with slots. Perhaps, I will not put electronic in the booster but in the sustainer. I just wanna be sure the altimeter will have plenty of time to ignite the second motor. Also, like boosters seems to need lot of power, longer booster give lot of room for bigger motor and for the laundry.

Make sure the arming altitude for the deployment is low enough that the booster only will move the whole rocket to that altitude. That way if the Sustainer fails to ignite, you still have the main chute deploy.

Crumb fire said:

+1 for longer booster.
Here's what I'm planning for the summer:
View attachment 249820
I'ts just another estes tube with slots. Perhaps, I will not put electronic in the booster but in the sustainer. I just wanna be sure the altimeter will have plenty of time to ignite the second motor. Also, like boosters seems to need lot of power, longer booster give lot of room for bigger motor and for the laundry.

View attachment 249824

Click to expand...

Why the smaller mount in the second stage?

Because I draw the original Leviathan and then decided to add a booster stage later after. Since nothing is glued, I still play with the idea to use 38mm motor mount for the sustainer. I have never done any two stages before this one. It's my first try. I have compiled the most information possible on this forum about 2-stage rockets. So my experience is limited to that of others ...I'm still looking for other's advice too.

The plan was to have my sustainer lit from the AV bay in the sustainer itself. There's plenty of room in the booster for a 12" parachute. I've cut the motor mount tube to be just a touch longer than an AT 29/40-120 casing. Leaves about 5" for the 'chute and shock cord. It SHOULD drag separate due to only 1/2" of coupler holding the booster to the sustainer, but I also plan on using an ejection charge. 1 second or so charge and the parachute is out and the rocket has rapidly moved away. 1.5 seconds after burnout and the sustainer will light. That's the plan, anyway.

I didn't realize so many people wouldn't look at the ORK file, which has all the parachutes and AV bay listed. My apologies for not making it clearer in my original post. Here's a picture of the configuration: