I'd like to introduce Slipstick IV, a rather slim bird for its size, that will fly at MHM. Its a two stage rocket, based on two Performance Rocketry G3's (ordered with custom modifications), using K700W's for the boost and for the sustainer. I'm hoping to bust 15840 ft to put me in the 3-mile high club. ❗ Details on request.

Sweet looking project Mike. I look forward to seeing it fly.

Warren

I just need to try and cut out some of the length where I can.

Looks great, Mike. What's your design for the staging?

Looks great, Mike. What's your design for the staging?

OK , since you asked, but keep in mind it changes every moment I work on it. Here's the basic concept. Its designed so that the wiring to the igniter is attached externally to two screws on the airframe which are soldered to copper foil traces going up to the timer just above the motor. This way that is the last thing to attach (for safety) once the rocket is vertical.

You will notice from the real picture of the rocket, that I have rounded off the fins, which is to reduce the area of the fin in the airstream that causes twisting moments at the fin span. Its supposed to hit Mach 1.2 and reach 17,000 feet.

Where new joints were added, the couplers are inserted 1-1/2 diameters into the airframe. This is in the middle where there is the most stress. I was stuck using 1 diameter where I was using existing rocket parts from my L2 bird Slipstick II, which is on the top and bottom of what is now Slipstick IV.

The separation and deployment of the booster is handled by a timer in the booster avbay which becomes the nose cone of the booster. I'd rather put a real altimeter in the boost section, and test for apogee deployment, rather than using a timer as shown. Want to donate one, for a beta test?

For a larger PDF of the above image, Click here: http://telerover.com/rockets/MS/G3_mods_two-stage_Rev7.pdf

Mike,

You don't want an altimeter in the booster. The PET will work great, since it's dual, you can do both the separation charge and deployment charge.

I was thinking further on the sustainer... Picture this, put the PET in the deployment ebay (so you only have 1 to deal with), with your sliding copper contacts going between the rear coupler of the ebay and the airframe copper strips. Drogue would deploy "up" as in traditional, rather than zipperless configuration. This would save you the weight of the extra bay and coupler, as well as take some length out. The drogue bay doesn't need to be very long for a small chute, streamer (or nothing).

Try to minimize connection points between your electronics and the motor. I've got fiberglass tubing conduits to route the ematch wiring up to the timer bay. So if I'm airstarting with 1 ematch, I've only got one connection point (at timer). If I'm using up to 6 ematches (6 outboards afterall), I have a buss board inbetween.

Just tossing ideas around!

Ken

Mike,

You don't want an altimeter in the booster. The PET will work great, since it's dual, you can do both the separation charge and deployment charge.

I was thinking further on the sustainer... Picture this, put the PET in the deployment ebay Ken

I've batted that one around a dozen times and settled on the above scenario. There is no room in the deployment avbay, Unless I buy a different timer. Greg Jeziorski, who seems to be very experienced at staging, suggested the altimeter because you never know when the booster will be the slowest to set a timer up correctly. He also suggest drag separation, but Doug Gerrard and Jim Amos both feel the booster needs to be blown off. I'm taking the best ideas from everybody, ...brainstorming is good.

Mike, you are amazing! Nothing more to say... just very impressive!

I'd be happy to loan a new Parrot V2 for your project, but I'm no longer confident that I will have units available by MHM. In the last week I've put in 70+ hours and two trips to Houston for my regular job, so I've fallen behind on altimeter development. And this is the last weekend before taxes due. Ugh. Your setup looks pretty bulletproof, though I'm curious what sort of lateral disturbances happen during the staging separation charge.

Sometime later this year I'm thinking of trying a much smaller 2-stage rocket (G37-E6), and for simplicity I'm thinking of having the upper stage ignited by an altimeter located in the booster. I've heard that this this method is less desirable, but I'm not clear on why. Opinions?

I'm thinking of having the upper stage ignited by an altimeter located in the booster. I've heard that this this method is less desirable, but I'm not clear on why. Opinions?

If your booster drag-separates, you've got no go for the sustainer.

Ken

You don't want an altimeter in the booster. The PET will work great, since it's dual, you can do both the separation charge and deployment charge.

Mike has to ignite the 2nd stage (1st) and deploy a chute (2nd) in the booster. Mike, while I haven't done this or air-starts yet, once the 2nd stage is ignited, you'll have no trouble with separation. If it doesn't ignite, the 2nd stage will deploy the drogue or main--whatever your flight plan is, just as if there weren't a booster... in theory. Of course the booster could fall off... use a PET2, and that'll blow the booster chute out. 😯 Keep it simple. 8)

The Quantum Leap used the Sustainer moter to blow the Booster section off and moter ejection for the Boosters Chute. Seams a lot simpler.
But what do I know, I never got to try it, considering I crunched the sustainer in December! 😥

I have plans for a 2 stage CF Bird for Octoberfest or MHM next year. Minimum diameter with an "L" in the bottom and "K" on top. Rocksim says 30,000 feet. Hope we can get the waiver. 🙄

Scott e

I'd like to introduce Slipstick IV, a rather slim bird for its size, that will fly at MHM. Its a two stage rocket, based on two Performance Rocketry G3's (ordered with custom modifications), using K700W's for the boost and for the sustainer. I'm hoping to bust 15840 ft to put me in the 3-mile high club. ❗ Details on request

Hey Mike
I know your fond of that name, but those roman numerals get mighty complicated the higher you go. 😉

Scott e

Hey Mike
I know your fond of that name, but those roman numerals get mighty complicated the higher you go. 😉

Scott e

Its a generational thing. Homer Hickam named all his rockets Auk, I, II, III, etc.

I was thinking of changing the sub name name of this bird to THE TWINS. The top would be Ricky (my sister) and the bottom Micky (me). This is what we were called when we were kids.

Bruce you are right if the upper stage lights it will cause separation but you will need to keep in mind venting the motor because some motors do not light well if there is no air and the extra drag up to the point the second motor lights and separates from booster. Some people will just put a small charge with no ematch in the interstage so that when the motor does light it helps blow things a part. I really do not think that is needed but... I personally like the idea of a separation charge and then the ignition of the motor. In using an altimeter or timer, they both would work but the altimeter takes the guess work out of it and will help minimize damage on booster deployment. The most important thing is to keep the ignition source on the sustainer and not the booster, it helps to insure the motor has a chance to light.