Going for 100,000 Feet

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First... subscribed... obviously!

Second, tried to get my school to do a 100k project, but of course $$ and policy were the front runners!

Third, a few questions...

1) Are you using the sustainer motor ignition to force the booster/sustainer separation,
or will it be a booster burnout separation / sustainer coast to ignition (boosted dart-ish)?

2) Have you approached the idea of putting the sustainer ignition electronics behind the motor
(hardened of course against the blast) within the booster?
Treat it essentially as an overgrown ejection ignition event? (have a few ideas about that, thanks SHC)

Willing to donate brain cells and design assist if you'd be willing;
might be able to enlist some help here in AL also!!

Thanks

fm

ps. obh, i'll be buying some harnesses from ya for my own birds, nice to see the support!!
 
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First... subscribed... obviously!

Second, tried to get my school to do a 100k project, but of course $$ and policy were the front runners!

Third, a few questions...

1) Are you using the sustainer motor ignition to force the booster/sustainer separation,
or will it be a booster burnout separation / sustainer coast to ignition (boosted dart-ish)?

2) Have you approached the idea of putting the sustainer ignition electronics behind the motor
(hardened of course against the blast) within the booster?
Treat it essentially as an overgrown ejection ignition event? (have a few ideas about that, thanks SHC)

Willing to donate brain cells and design assist if you'd be willing;
might be able to enlist some help here in AL also!!

Thanks

fm

ps. obh, i'll be buying some harnesses from ya for my own birds, nice to see the support!!

Typically on high power two stagers the booster separates long before the sustainer is ignited. There is no reason to carry the extra drag along for the ride, also depending on the booster burnout velocity you might want to burn off some speed before igniting the sustainer.
 
... When you say you're limited to "M power" do you mean total installed impulse or do you mean largest booster motor? That's a big difference.
My opinion based on seeing others high altitude projects, and working on some of my own:
One is near impossible and one is pretty damn hard. I definitely think you'll have trouble doing this with "hobby" methods. Maybe with research into high strength-weight composite structures, flying cases, experimental deployment methods, head end ignition, and (dare I say it) EX.

If you're limiting yourself to 10,200 Ns, you really have your work cut out for you, and I'm almost positive it's not possible with hobby motors. You might have luck with a Loki Dart based design, and an experimental fast burning full M with a crazy high mass fraction. To prefect something like that would definitely take a lot of engineering and experimenting.

Using an M as a booster might be a little easier. I could imagine an extremely optimized M2245 - L935 making it close under the right conditions. Still, I would imagine it would have to be meticulously designed and built (practically flawless).
I'd recommend you consider EX motors. They have some distinct advantages over a commercial motors. Mainly, they allow you to run lower margins the comm motors, allowing you to save weight. Running small margins requires great EX techniques and a through understanding of motor design. It's difficult to do, but I've seen it done and the weight savings really pay off. Flying EX also allows you to more easily integrate the motor into your design. This would solve your coupler problem, head end ignition problem and allow you to eliminate dead space. In my recent "I.D.S.S." build, my motor's forward closure is also the aft bulkhead to my AV bay, which allows me to reduce the space between the forward closure and the base of the nosecone to about 2in or so. Those kind of space savings mean everything in a project like this. Yes, it will be a larger time investment and yes, the start up costs are more expensive, but take a look into motor design and you might be a bit closer to your goal.
IMHO, you should spend your "test" build researching optimization and space saving methods.

Off my soapbox.

Alex
 
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.
Really. There is absolutely nothing to debate.

If you have a manufacturer's part for a head end ignition forward closure for that casing, then it is a certified commercial motor. I fairly certain that not one of the 2000+ certified motors on the combined list employs head end ignition, so I am unaware of any motor manufacturer offer such a forward closure. But I could have missed one.

If you decide to modify the forward closure for head end ignition, the casing and the reload within it is no longer certified. It can be flown at a TRA launch as a research motor, but not at a NAR launch.

This is the official ruling as per NFPA 1125. If you want to change NFPA 1125, good luck.
 
If you have a manufacturer's part for a head end ignition forward closure for that casing, then it is a certified commercial motor. I fairly certain that not one of the 2000+ certified motors on the combined list employs head end ignition, so I am unaware of any motor manufacturer offer such a forward closure. But I could have missed one.

Legit question here- Loki makes HEI capable forwards for 54 and 76
https://lokiresearch.com/secure/storeDetail.asp?id=737157636580
https://lokiresearch.com/secure/storeDetail.asp?id=737157636580

Are those considered certified for HEI, or would he have to submit them for approval and testing first?
 
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Legit question here- Loki makes HEI capable forwards for 54 and 76
https://lokiresearch.com/secure/storeDetail.asp?id=737157636580
https://lokiresearch.com/secure/storeDetail.asp?id=737157636580

Are those considered certified for HEI, or would he have to submit them for approval and testing first?
I can't answer for TRA TMT, but for NAR S&T, he would have to certify the HEI design with a hydrostatic proof test (for casing pressure integrity), and then submit a couple reloads for each casing size to be fired on the S&T test stand (for the purpose to illustrate functionality, and reliability). If the certification tests were successful, I would be willing to approve the HEI units for each of the casing diameters that were tested. They would be certified as a plugged motor, so electronic recovery would be required for these motors.
 
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?

View attachment 293524
It's very ambitious, and difficult, but your approach is correct: use sub-scale test flights as a proof of concept.

Your H impulse 2-stager is good first step. I would investigate using other engines however as the specific impulse of the one's you chose is low.

Ideally you want the first stage a light as possible, to maximize the mass and sectional density of the second stage. The will allow the second stage to coast higher and farther than a lower sectional density rocket as drag is determined by shape, and the retained momentum of the heavier upper stage will reducethe deceleration rate and allow for a higher velocity coast which leads to a higher apogee.

The higher the Isp of the propellant, the more ballast can be added to the second stage to maximize the coast distance.

There are 3 3G-Pro29 reloads with higher specific impulse than the 4G-Pro29 reload you have proposed. Take the extra mass and put it in the second stage.

Similarly, you may gain retained momentum and suffer less gravity loss by using the Blue Streak or Pink reloads in the second stage instead of the long burn.

Make sure you run a lot of accurate sims. They will pay off in the end.

Looking forward to your flight report.
 
I can't answer for TRA TMT, but for NAR S&T, he would have to certify the HEI design with a hydrostatic proof test (for casing pressure integrity), and then submit a couple reloads for each casing size to be fired on the S&T test stand (for the purpose to illustrate functionality, and reliability). If the certification tests were successful, I would be willing to approve the HEI units for each of the casing diameters that were tested. They would be certified as a plugged motor, so electronic recovery would be required for these motors.

Thanks for the quick reply.

To clarify for anyone else reading, I know these bulkheads were used when certifying the L1040 54/2800 and L2050 54/4000, so the part itself is legit, just asking Bob about the HEI feature and what it would take to certify. (Loki 54 and 76 are all plugged motors, so no delay concerns there).

But, as Bob said earlier, going HEI is good to go as EX. Personally, back on topic, I think Evan should grab a loki 76/8000 case, wait for Scott to get the new red baby N for that case ready, and stack a 54/4000 baby M on top of it. I have no idea if it'd hit 100K, but it'd be a hell of a show.
 
Personally, back on topic, I think Evan should grab a loki 76/8000 case, wait for Scott to get the new red baby N for that case ready, and stack a 54/4000 baby M on top of it. I have no idea if it'd hit 100K, but it'd be a hell of a show.

Exactly my next project. Black Rock, sometime 2017
 
I will donate electronics for this project.

I would love that, John. Thank you. It will be down the road, but if you have some desings that will fit a 38mm tube that you want to test, I'd be happy to use them as well. You would definitely be listed as a sponsor.
 
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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.

Not a bad idea.
 
It's very ambitious, and difficult, but your approach is correct: use sub-scale test flights as a proof of concept.

Your H impulse 2-stager is good first step. I would investigate using other engines however as the specific impulse of the one's you chose is low.

Ideally you want the first stage a light as possible, to maximize the mass and sectional density of the second stage. The will allow the second stage to coast higher and farther than a lower sectional density rocket as drag is determined by shape, and the retained momentum of the heavier upper stage will reducethe deceleration rate and allow for a higher velocity coast which leads to a higher apogee.

The higher the Isp of the propellant, the more ballast can be added to the second stage to maximize the coast distance.

It is looking more like the first project will focus on a 2-stage I rocket. I cannot seem to find 24mm nose cones and beeline trackers will not fit into a 24mm tube.

There are 3 3G-Pro29 reloads with higher specific impulse than the 4G-Pro29 reload you have proposed. Take the extra mass and put it in the second stage.

Similarly, you may gain retained momentum and suffer less gravity loss by using the Blue Streak or Pink reloads in the second stage instead of the long burn.

Make sure you run a lot of accurate sims. They will pay off in the end.

Looking forward to your flight report.

Doing a lot of Sims with Open Rocket. There does seem to be an optimal weight for the sustainer. Not too heavy, not too light. Also adding a 1-degree cant to the sustainer fins dramatically increases Mach 2+ stability and also adds a little altitude.

The final M rocket will be a CF construction using tip-to-tip CF on the fins to ensure they stay in place. So my thought is that the final M-powered 2 stage rocket should have a top speed under Mach 3, which would significantly reduce risk of shred. More speed does not necessarily translate to more altitude. If the final coast starts at a higher altitude then it can be done at a lower speed.

For instance, the current motor configuration in the M rocket is an M1590 booster (7561 NS) and an L265 sustainer (2,646 NS - total of 10,187 NS - 99.5% of a total M) Sims to an altitude of 116,200', but only hits a top speed of Mach 2.96. If I change the configuration to an M2150 booster (7443 NS) and an L990 sustainer (2765 NS - Total of 10,208 NS - 99.7% of a total M), It sims to 113,500' with a top speed of Mach 3.77. The difference is that the sustainer motor burns out at approx. 47,000' with the longburn motors and a little north of 25,000' with the shorter burn motors ... delay to airstart is the same in both scenarios (7 sec.). Top speed is achieved at approx. 28K feet with the longer burn and 22K feet with the shorter.

Since I am not going for a speed record it makes more sense to achieve a lower top speed at a higher altitude and have much less friction and heat to deal with on nose cone tips and fin leading edges than the opposite. Especially since the max altitude of both sims is roughly the same.
 
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.
Cool. Motor ignition of the sustainer happens high enough that there should be little risk.
 
Exactly my next project. Black Rock, sometime 2017

My thought is closer to 2019. My youngest son is in high school until June of 2019, and it makes the most sense to do this at BALLS, which happens in September, when school is in session.
 
Thanks for the quick reply.

To clarify for anyone else reading, I know these bulkheads were used when certifying the L1040 54/2800 and L2050 54/4000, so the part itself is legit, just asking Bob about the HEI feature and what it would take to certify. (Loki 54 and 76 are all plugged motors, so no delay concerns there).

But, as Bob said earlier, going HEI is good to go as EX. Personally, back on topic, I think Evan should grab a loki 76/8000 case, wait for Scott to get the new red baby N for that case ready, and stack a 54/4000 baby M on top of it. I have no idea if it'd hit 100K, but it'd be a hell of a show.

My personal challenge is to hit 100K feet on M power.
 
So these are the current designs.

"Do", which will fly sometime next year, most likely in Potter but I would need to control the altitude just a little, would fly on 2X H255. This works out to about 98% of an I. Simmed altitude under the very best conditions is 22K feet. but most likely will come in at about 20K. Top speed is Mach 1.96. Construction would be glass-wrapped Bluetube with 1/16" G10 FG fins and a foam-filled plastic nose cone unless I can find an ogive FG nose cone. Conical nosecones are available but apogee suffers by as much as 4,000'. IF HEI is not allowed, I think I could use flat wire for the sustainer. I would be looking to do this in 2017. This is to test staging and airstarting after a delay. If successful, this would set an I multi-stage altitude record.
I- Rocket.jpg

"Re" would be all FG construction. Right now I am using a 54mm to 29mm tube configuration with a K600 booster and an I243 sustainer. This is to test construction. All FG with Tip-to-tip fins. Max altitude is approx. 46,000' and it should top out at Mach 2.5. If I cannot find a 29mm FG nose cone, I may have to make the sustainer 38mm instead. That configuration would be a K400 booster to a J150 Sustainer. <ax altitude is approx. 41,000' and top speed is mach 2.15. This would happen somewhere in the Midwest or south where there is an event with a 50K waiver in 2018, and if successful would set a K multi-stage altitude record. There is a possibility of this happening in 2017. We are currently planning on going to Wyoming for the Solar Eclipse if budget allows (Not only to travel there, but to buy a solar telescope). If there is an event nearby, I could build Re in time for that event.
K-Rocket.jpg


"Mi" Is the Big one. Current configuration is an M1590 booster and an L265 sustainer. Simmed altitude is 116K feet at MSL - 135K feet at Black Rock. Top speed, Mac 2.96, I am shooting for BALLS 2019 to do this one.

M Rocket.jpg

As I said at the outset, this is a long term project. I want to take my time and do it right because I only have one shot. In the meantime I will be building other rockets that should help me gain additional learings. For instance, I plan on flying my first HPR 2-stage some time this fall at Potter. The rocket is called the Bull Shark and there is a thread to its construction. It will fly on G and H 38mm motors.
 
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First... subscribed... obviously!

Second, tried to get my school to do a 100k project, but of course $$ and policy were the front runners!

Third, a few questions...

1) Are you using the sustainer motor ignition to force the booster/sustainer separation,
or will it be a booster burnout separation / sustainer coast to ignition (boosted dart-ish)?

2) Have you approached the idea of putting the sustainer ignition electronics behind the motor
(hardened of course against the blast) within the booster?
Treat it essentially as an overgrown ejection ignition event? (have a few ideas about that, thanks SHC)

Willing to donate brain cells and design assist if you'd be willing;
might be able to enlist some help here in AL also!!

Thanks

fm

ps. obh, i'll be buying some harnesses from ya for my own birds, nice to see the support!!

1... Separation will be with pyrotechnics fired from the booster. In the smaller test rockets, the motor ejection charge will deploy the recovery systems. In the final M project, the sustainer will coast about 7 sec. before airstarting. Any more than that and I risk it coasting back below transonic speeds. Once the rocket goes above Mach 1.2 it should stay above it until the sustainer motor burns out. Less wear and tear. Less risk of shred. The booster recovery will be fired from 2 pair of timers (redundant recovery).
2... If the booster stays attached to the sustainer during the interstage coast phase, I will get a lot less altitude. Best thing to do is to shed the booster as soon as the motor burns out. No sense in keeping that added weight. So 2nd stage ignition must originate from the e-bay in the sustainer. This can happen from head-end ignition or from flat wires. If the flat wires are external, I will probably need another wrap of CF over top of them to ensure they will stay attached.
 
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Cool. Motor ignition of the sustainer happens high enough that there should be little risk.

Yep. Just program an "altitude@time" or some other such lockout and we've got the space to be very comfortable with staging.
 
Yep. Just program an "altitude@time" or some other such lockout and we've got the space to be very comfortable with staging.

I just need about 5 guys there with trackers set to my frequency to find the f-----g thing. Actually, the first one will be single deploy of a streamer at altitude. I'm thinking a 10' long mylar streamer that reflects a lot of light in addition to the tracker.
 
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The booster recovery will be fired from 2 pair of timers

Why timers?
Pretty crude and require accurate sims.
What's wrong with a traditional altimeter taking care of apogee (or Dual-Deploy) for the booster.
 
The booster recovery will be fired from 2 pair of timers

Why timers?
Pretty crude and require accurate sims.
What's wrong with a traditional altimeter taking care of apogee (or Dual-Deploy) for the booster.

I was concerned about space and wiring. There are timers are less than half the size of even the smallest DD altimeters. I also need a timer to fire the separation charge. So if I have a pair of altimeters, I still need a pair of timers. Either way, I need 4 pieced of electronics. Even in the final rocket, there isn't much room in the booster. for recovery and deployment.

So why not replace the pair of altimeters with a second pair of timers to deploy the booster main and save the space and to a lesser extent, the weight. Have the second timer set to about 0.5 to 1 sec. before simmed apogee. Wiring of individual timers is also much simpler and I do not have to fret about cramming wire into the AV bay area. And finally... with timers, I would not need vent holes drilled into my transition. I would need the one vent hole in the airframe to prevent pressure separation, but that would be it.

The alternative would be to use something like a Featherweight altimeter or similar that has an accelerometer component and fires up to 4 events including booster separation, but two of these still take up more space than 4 timers.
 
I was concerned about space and wiring. There are timers are less than half the size of even the smallest DD altimeters. I also need a timer to fire the separation charge.

You can fire the separation charges with a Marsa54L-MarsaNet. You have up to 9 channels and 9 independent events with the system. You can also do your booster recovery with a MrfPyro unit in the booster. One MrfPyro channel to fire the separation charge, the other MrfPyro channel to deploy the recovery after a set delay after separation.
 
MT4 is 1x1 SLCF is 2x1. For the function added I think it's worth the size. I'd go so far as to use a single altimeter over 2 timers.

EDIT- I'd still use a single altimeter, but I see how you're looking at the timers here. We all we thinking "set a timer and go", but the MT4 does have a burnout setting....which would essentially be the same way I'd use an altimeter...... So the functioning is going to be mostly the same..... either tool you're doing "fire at burnout, fire at burnout +X"

For the main event I'm with John.
 
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Yes - use MarsaNet devices....skip all the wiring issues....
This is why I suggested them and you would be wise to take John up on his generous offered to donate.

Use a "flight computer" to make intelligent, real-time decisions about when to separate, ignite and deploy.
Timer's should be avoided....today's solutions are SO much better....safer....
 
You can fire the separation charges with a Marsa54L-MarsaNet. You have up to 9 channels and 9 independent events with the system. You can also do your booster recovery with a MrfPyro unit in the booster. One MrfPyro channel to fire the separation charge, the other MrfPyro channel to deploy the recovery after a set delay after separation.
.

That was essentially my thought. Although in the smaller rockets that have 29mm sustainers I would need much smaller electronics.

I am looking at the main event rocket as requiring redundant recovery systems. So I would use 2 MrfPyro units...one as primary for both events and one as backup for both events. That places additional challenges on space allocation. Am I wrong in thinking this way? Plus, If I'm sending a rocket up 100,000, I want to get a video of it.
 
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Yes - use MarsaNet devices....skip all the wiring issues....
This is why I suggested them and you would be wise to take John up on his generous offered to donate.

Use a "flight computer" to make intelligent, real-time decisions about when to separate, ignite and deploy.
Timer's should be avoided....today's solutions are SO much better....safer....

I agree with your principle, Fred. My intention all along for the main event was to use MARSA components because they link very well to each other and the wireless connections become great space savers. John's offer is extremely generous.

However principles get challenged by reality. In designing these rockets and laying out the electronics we also have to do with the confines of space. What ever electronics I use have to fit into tiny spaces, so there needs to be tradeoffs between what is desired and what fits.

in the 29mm min. dia. test flights, I will be extensively challenged with space issues. Part of the learning with them is figuring out how to configure electronics in such a way that space is maximized. By maximizing space inside a 29mm tube, I discover new options inside a 54mm tube.

Since the first rocket is small, I could do without the redundancy and I could use streamer deployment, dispensing with a main parachute. However I will need something like an MT4 that as a rudimentary accelerometer and can sense motor burnout and airstart the sustainer motor. Timers like it can fit inside a 29mm tube on the opposite side of a sled holding an Eggtimer Quark, Stratologger CF, RRC2, or another altimeter that size, and both can run off the same battery.

In "Do", I am dealing with a payload bay that is essentially 8.2 cubic inches in the sustainer and 2.8 cubic inches in the booster. With in the 8.2 cubic inches I need to be able to locate an altimeter, timer, tracker/transmitter, and batteries as well as wiring. Within the 2.8 cubic inches of the booster I need to locate a timer and a battery. Both situations are doable. I have crammed a lot of electronics in small rockets before. But they need very small components.

The reason to start small and work up is so that you can see, correct, and/or enhance the design, then build the next rocket up the line. That will be important because in the main rocket, I will need to position 2 MARSA altimeters, 2 batteries, and a 2 small video cameras inside a 35.5 cubic inch cylinder that is a little more than 2" in diameter. The ideas to maximize the 35.5 Cu. in...will come out of how I maximized 8.2 cu. in.
 
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