Going for 100,000 Feet

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EeebeeE

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Many of you followed the thread of my Rocketry Warehouse Terminator as I went through the build and then successfully flew it to achieve my Level 3 certification. For many, this is a goal that allows them to fly big and glorious rockets with fantastic displays of airpower and recovery systems.

I wanted my L3 for a different reason. I wanted to fly a rocket to 100,000' at least once during my lifetime. But here's the thing...I don't have a huge budget, so I need to do it on M power. It's possible. The math works. But I will have one shot at this... so I need to get it right the first time.

So this will be a very long-term thread. There will be gaps as I work on other projects, and then there will be flurries of activity. This will not be a single rocket build, but rather a series of builds to test designs, materials, build techniques, staging ideas, and more. Along the way, I hope to set some records. It would be kind of cool to be in the record book at least once in a while.

Ideas and insight are very welcome as I work through this challenge. I will need thought into electronics that can handle 100,000'+ altitudes, advanced recovery techniques with small transmitters, fitting in redundant electronics, transmitters, and a video cameras inside minimum diameter airframes, high-temp epoxy, and a whole bunch of stuff I probably haven't thought about.

But for now, I should start at the very beginning. A very good place to start. When you read you begin with "A B C." When you sing you begin with "Do Re Mi."

So my first design will be Do. The first note of the scale. The purpose of this design is to test two minimum diameter stages and determine these critical elements:
1. Can the motor serve as a coupler to hold stages together?
2. Can very thin telephone wire, epoxied to the outside of the airframe, be enough to ignite the sustainer motor?

Do will be first tested as a single stage to ensure that the sustainer is stable. It will fly on 6-grain 24mm G motors. Because it will ultimately push Mach 2, it will be too heavy to break the TRA single altitude G record. BUT, It will then attempt the H staged record. Then later the I staged record. Then possibly the J staged records. This will challenge the build techniques because with a full 640 NS, Do will go well past Mach 1.5, and with a full 1,280 NS, it will punch past Mach 2.

So this is Do set up with a CTI H123 booster and a G65 sustainer. Combined it is just under 320 NS, so it should qualify as an H-powered altitude record setter.

What do you think?

Do.jpg
 
Separation will occur with electronics in the booster. I will use motor deploy for the booster chute. The sustainer will need wire leads expoxied along the airframe then extending into the motor. The igniter will be soldered to these leads.
 
Oh, I'm definitely watching too. I've dreamed of a 100k buster myself -- nowhere close, at the moment. But maybe sometime. I like the way you are thinking, starting with small designs to test minimal design questions and then to sneak up on the goal.

Best of luck!

Martin Jay McKee
 
1. Can the motor serve as a coupler to hold stages together?

You could use a snap ring case, remove the thrust ring from the outside, and either friction fit the motor, or use one of the foreward retention bulkheads.
 
You could use a snap ring case, remove the thrust ring from the outside, and either friction fit the motor, or use one of the foreward retention bulkheads.

I was thinking that. For the smaller CTI motors that have an aft ring, I could also fabricate a ring that screws into the threads but does not have a thrust ring. Do will have a motor block to hold the 24mm motor in place and then be friction fit.
 
Here is a picture of a 2.5" M that was used as a coupler. I had two motor diameters length into the transition. Many will tell you that one caliber is all that is needed but two makes everything less wobbly.
I would use larger fins on the booster. They will give a straighter launch and the drag for the few seconds the booster is attached men's little compared to off vertical. Weather cocking is not an issue, if it is that windy you will not be launching to 100k.

Mark

Yea, it's bent. It fell a really long way.

https://www.ahpra.org/UPPERTB2 r.JPG
 
HEI (Head End Ignition) makes things so much easier.
Also, admittedly somewhat expensive, so does using MARSANET electronics.
 
HEI (Head End Ignition) makes things so much easier.
Also, admittedly somewhat expensive, so does using MARSANET electronics.

Remove smoke charge, thread ignitor through smoke well and epoxy seal the smoke well shut inside and out. I know that I can thread an ignitor through the 29mm smoke well, dont know about the 24mm.
If he is using CTi 24mm, this simple idea may work since the forward closure is throw away anyhow.
It would though change it to 'EX', as would using a rear closure that isn't the one that came with the motor (altering motors)
 
Remove smoke charge, thread ignitor through smoke well and epoxy seal the smoke well shut inside and out. I know that I can thread an ignitor through the 29mm smoke well, dont know about the 24mm.
If he is using CTi 24mm, this simple idea may work since the forward closure is throw away anyhow.
It would though change it to 'EX', as would using a rear closure that isn't the one that came with the motor (altering motors)

There was a very long debate a while back about whether modifying commercial motors qualified as ex or was just not allowed. I don't want to rehash it, only to warn anyone doing so to do some research before hand.
 
If I could subscribe twice to this thread, I would do it.

Good luck!
 
Remove smoke charge, thread ignitor through smoke well and epoxy seal the smoke well shut inside and out. I know that I can thread an ignitor through the 29mm smoke well, dont know about the 24mm.
If he is using CTi 24mm, this simple idea may work since the forward closure is throw away anyhow.
It would though change it to 'EX', as would using a rear closure that isn't the one that came with the motor (altering motors)

I imagine, drilling out the hole a little could be done if necessary. This idea can work with 24mm - 38mm motors which I have no problem friction fitting. The 100K design uses a 54mm sustainer and also I would want some more positive retention. Using this method would mean not being able to have an internal motor retainer. The other option would be to glue the case into the airframe.
 
There was a very long debate a while back about whether modifying commercial motors qualified as ex or was just not allowed. I don't want to rehash it, only to warn anyone doing so to do some research before hand.

The closure comes with the case in 24 and 29mm motors. Is there an issue about making alterations to the motor case? I would use commercial reloads. What I need in the sustainer is an aft closure that does not act like a thrust ring as well. It needs to be the same diameter as the case. An internal motor block forward of the motor would prevent the motor from going through the rocket so that the thrust ring on the closure would be unnecessary.

This is only an issue for the sustainer. The booster can still have a thrust ring.
 
HEI (Head End Ignition) makes things so much easier.
Also, admittedly somewhat expensive, so does using MARSANET electronics.

Up until the final flight, MARSA electronics are too large. For the 100K flight it makes perfect sense because the newer versions will fit into a 54mm airframe, and some of the modular add-ons John makes would be ideal for this.
 
I don't know enough to be of help to you, but I wish you every success. And I'll be able to say, "I knew him when...." :)
 
Up until the final flight, MARSA electronics are too large. For the 100K flight it makes perfect sense because the newer versions will fit into a 54mm airframe, and some of the modular add-ons John makes would be ideal for this.

I will donate electronics for this project.
 
The closure comes with the case in 24 and 29mm motors. Is there an issue about making alterations to the motor case? I would use commercial reloads. What I need in the sustainer is an aft closure that does not act like a thrust ring as well. It needs to be the same diameter as the case. An internal motor block forward of the motor would prevent the motor from going through the rocket so that the thrust ring on the closure would be unnecessary.

This is only an issue for the sustainer. The booster can still have a thrust ring.

This is the thread it came up in:

https://www.rocketryforum.com/showthread.php?t=125064
 
This looks like fun. This one is over my head, but logistically id take two paths at the same time to get there. One a two stage tank to get used to staging MARSA gear, the other progressively larger two stage MD to get used to those builds.
 
Unless someone from TRA specifically says no, I doubt you'll have any issues flying head end at URRG. Id let it fly if I'm LD.
 
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