Going for 100,000 Feet

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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?

That is correct. I run 2 MarsaNet's on my HoJo.

We can package 2 54LHD's in a 54mm tube easily. I can do a custom printed sled package that will mount the 2 altimeters, routers and batteries in a nice slide in compact package. We can collaborate the exact geometry when you are ready for this step.

Remember with the wireless you can put the altimeters anywhere in the booster. They do not need to "straddle" the charges as in a conventional wired av-bay DD arrangement.
 
"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.

My personal challenge is to hit 100K feet on M power.

I suggest a new challenge then, hit 125,000 feet with a 3" diameter vehicle. ;-) I really feel there needs to be a new set of "records" if you will, that of vehicle size. K's are no longer limited to 54mm, M's are no longer limited and 75/76mm, N's are no longer limited to 98mm and O's are no longer limited to >98mm. There are becoming a new class of high altitude rockets that are smaller in diameter and longer than those of yesterday, and these new rockets will be achieving much higher altitudes than any previous rockets of the same diameters. Introduce the "Diameter Class" Altitude Record. Just for kicks, somebody sim an L-2050-LW to an L-1040-LR and tell me what you get. That's 8,510Ns total installed impulse.


For the big one, I would suggest investing in the Loki Research 76/8000 hardware and using the Loki Red reload when it becomes available.
Here is a video of a test fire below. ~10,500Ns and a ~6 second burn. I can't give you an availability date, but BALLS 2019 won't be an issue.

For the sustainer I would suggest the 54/2800 with the L-1040, 3,708Ns and 3.6 seconds. The sustainer lacks the burn time of the L265, but puts out over 1,000Ns more impulse. The booster motors 6 second burn and ~3,000+Ns will put the sustainer up higher into thinner air and I'm confident the overall increased Ns will more than out weigh any drag penalties from going faster. In short, your chances of hitting 100K' would be greatly increasesd. Another bonus is, Loki Research 54mm and 76mm bulkheads are already able to accommodate head end motor ignition.

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).

I tried to do this with TMT, but was told they would not certify HEI, but only allow it for EX use. Something about insurance and safety, which I thought was umm..... well it didn't make any sense to me at all. They were afraid Joe Rocket would prep his 2-stage and HEI under his EZ-up next to everyone else and have an accident, rather than following the safety code or the page long safety instructions I wrote out for the correct, safe use of the Loki Research HEI units. They feel it is a safe course of action to let EX'rers go it alone on their own and hope they figure it out right on their own. I thought having a safe plan of action (with directions included) that was laid out and approved for use in one manner only would be the safest way. Turns out I was wrong.

Forgive me if the instructions need a correction or two. They never made it past this point. I have about 5-6 units made up but they do require hazmat shipping. I am open to any good suggestions for edits.

[video=youtube;NU2hxbzxCLs]https://www.youtube.com/watch?v=NU2hxbzxCLs[/video]
 
I suggest a new challenge then, hit 125,000 feet with a 3" diameter vehicle.

Always a possibility if TRA or NAR changes how they keep them, but getting them to make wholesale changes like that can be like steering a battleship. There is currently a category for Complex M. No one has set it, but it is there. I also think there is a natural challenge of 100M feet on M power. Essentially about 10 feet per Newton-Second.

I'm not married to HEI. I think flat wire could work as well, whether or not it is molded into the airframe or attached to the motor case. If it is destroyed by the motor heat, it won't be that critical since by then it would have done its job. What I need though are sustainer cases that have no thrust rings. I would need these in 29mm, possibly 38mm, and 54mm. I see that Loki's 29mm production is currently on hold. Any plans of bringing it back?
 
Or 100K with 54mm... the 54/4000 M red to the 38/1200 K red I can sim to ~140K in OR (albeit with a design needing some pretty advanced construction techniques and approx. thrust curves). Will be flying a 38mm MD in two weeks that would work as the sustainer for this sort of design to give me an idea of the achievable real-world performance.
 
EeebeeE said:
I see that Loki's 29mm production is currently on hold. Any plans of bringing it back?

Unfortunately no, there are no plans at this time. I need a lot more business to pull that off. You can remove the thrust ring though on any current Loki hardware, old 29mm included.

RocketHunter said:
Will be flying a 38mm MD in two weeks that would work as the sustainer for this sort of design to give me an idea of the achievable real-world performance.

Correction..... you'll be flying a 1,518.7Ns K-627 Loki Red in your 38mm MD in 2 weeks. Teddy at One Bad Hawk has a pair coming. I assume one is for you. ;-)
For those with their jaw on the keyboard, this is for the 38/1200 hardware using a #25 nozzle, not the #28.

The motor was announced at the LDRS banquet last night along with 5 other 38's. No Red 54mm M just yet. The first tested as an M-1378, 5,363Ns, 3.89 seconds. The second had some fit issues and hasn't been burned yet.
 
Or 100K with 54mm... the 54/4000 M red to the 38/1200 K red I can sim to ~140K in OR (albeit with a design needing some pretty advanced construction techniques and approx. thrust curves). Will be flying a 38mm MD in two weeks that would work as the sustainer for this sort of design to give me an idea of the achievable real-world performance.

I see 100M on M Power as real world performance although a 54mm attempt at 100M would be ambitious as well.

Ultimately, though, Records by impulse are more challenging than records by diameter, because you cannot exceed a specific impulse, but you can build a longer rocket. Hypothetically, You could build a 3" minimum diameter 4-stage rocket with 3x Loki N3800 and A Loki L 480. That's pushing a full O.

As new longer cases are manufactured it is easier to break the record. But if you restrict total NS...then build technique, design, and other finer elements come more into play.
 
I see 100M on M Power as real world performance although a 54mm attempt at 100M would be ambitious as well.

Ultimately, though, Records by impulse are more challenging than records by diameter, because you cannot exceed a specific impulse, but you can build a longer rocket. Hypothetically, You could build a 3" minimum diameter 4-stage rocket with 3x Loki N3800 and A Loki L 480. That's pushing a full O.

As new longer cases are manufactured it is easier to break the record. But if you restrict total NS...then build technique, design, and other finer elements come more into play.

I guess whats really interesting with the longer reloads is that it gives an alternative way to get impulse class records - like say going for the I impulse record with an ultra optimized 29mm MD with a 20% I versus an inherently higher drag 38mm 100% I. Same with say the L record - currently held with a full L 75mm, but the 54mm Loki L1040 or L2050, while lower impulse, could match or exceed that record.

Motors can only get so long before they become impractical/inefficient/unreliable. In an ideal world, one would design their own motor that was the full impulse for a specific motor class and at the exact diameter where it was as long as possible - giving the lowest drag with highest impulse. But many times the impulse divisions fall at awkward spots and force compromises, so that even with a perfectly optimized rocket that given amount of impulse could still theoretically push a rocket higher with a more optimally sized motor.
 
As new longer cases are manufactured it is easier to break the record. But if you restrict total NS...then build technique, design, and other finer elements come more into play.

Look at the N-5800 contest for the N-record. Most people would not call that an easy thing to do, and many nice designs failed trying. I do not at all mean to be argumentative, but for the sake of discussion, I would say all of those same skills come into play with a vehicle exceeding M3, and then double the skill required if it were a 2-stage going as fast and faster. Motor class records are more like bracket racing to me I guess. I suppose I've always enjoyed the Unlimited Class the most. Maybe that's what I'm asking for???

I see they have something similar to this for EX'ers, but not for commercial motors in section - 8.0 Research Motor Altitude Competition- Individual.
Maybe this could be changed to be open to any motor (not just EX) or have a commercial category as well.

I don't mean to sidetrack the thread here, but I have been wanting to bring this records thing up at some point. This thread brought it out of me. Sorry. We can discuss it elsewhere if someone wishes to rather than sidetrack your thread.
 
A discussion of records would be interesting. It seems to be very inactive even after they dropped the altimeter requirements to something sane.

EX is practically unused, and the commercial haven't changed in forever it seems.
 
Look at the N-5800 contest for the N-record. Most people would not call that an easy thing to do, and many nice designs failed trying. I do not at all mean to be argumentative, but for the sake of discussion, I would say all of those same skills come into play with a vehicle exceeding M3, and then double the skill required if it were a 2-stage going as fast and faster. Motor class records are more like bracket racing to me I guess. I suppose I've always enjoyed the Unlimited Class the most. Maybe that's what I'm asking for???

I see they have something similar to this for EX'ers, but not for commercial motors in section - 8.0 Research Motor Altitude Competition- Individual.
Maybe this could be changed to be open to any motor (not just EX) or have a commercial category as well.

I don't mean to sidetrack the thread here, but I have been wanting to bring this records thing up at some point. This thread brought it out of me. Sorry. We can discuss it elsewhere if someone wishes to rather than sidetrack your thread.

Not suggesting that any altitude record is "easy." Just that impulse level records will get progressively harder to break, where diameter records will increase at a greater extent as technology increases, such as larger motors and longer airframes.

It is worth a thread. David is right in that we should review these. We should look beyond altitude as well. I got a lot of flak from a number of people because I felt that the full-scale V-2 flight in Australia was not successful because the fincan suffered severe damage when it landed. Had that been an L3 attempt, the L3CC would not have certified it. They did not use a large enough chute and the onboard video showed a lot of buckling in the fins as it hit the ground. If one of the records is going to be "largest amateur rocket" then there needs to be more specific documentation. Self-proclaimed records do not impress me.

But that is another discussion for another thread.

I am just about set to order parts for this first build, "Do." I think URRF in 2017 would be a good time to fly it. All of these flights will need to be at events where a large number of sanctioning people are so they can provide documentation that a record was set.

At my wife's request I am taking a summer off rocketry, so this is a fall build.
 
.... you'll be flying a 1,518.7Ns K-627 Loki Red in your 38mm MD in 2 weeks. Teddy at One Bad Hawk has a pair coming. I assume one is for you. ;-)
For those with their jaw on the keyboard, this is for the 38/1200 hardware using a #25 nozzle, not the #28....
Not to derail the thread, but I think I just found the motor for my BALLS 2 stage sustainer! It's a (nominal) 38mm sustainer riding on a 4" booster. 1518 Ns is about 60% more Ns than the long-burn 'Mellow Yellow' CTI motor I was going to use. Should really goose my overall altitude.

Wow, that is a great sounding motor. Really looking forward to it.


Tony
 
Hey all!

I do not have too much experience with high altitude, mach breaking simulation software vs. real world flight data, but isn't RASAero II what really should be used for simulating high altitude, mach breaking flights?
 
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.

we designed our IREC bird to use a charge to separate the dart from our booster
 
So I finally figured out RASAero II and was able to run a sim on Do using 2 x H255 motors.

RASAero projected 18,117 feet in altitude and a max. velocity of Mach 2.01
By comparison Open Rocket projected 18,239' at Mach 2.08

The altitude estimations differences are not significant, and the Mach differences are barely significant. Both pieces of software have their strengths and weaknesses.
 
So I finally figured out RASAero II and was able to run a sim on Do using 2 x H255 motors.

RASAero projected 18,117 feet in altitude and a max. velocity of Mach 2.01
By comparison Open Rocket projected 18,239' at Mach 2.08

The altitude estimations differences are not significant, and the Mach differences are barely significant. Both pieces of software have their strengths and weaknesses.
Did you include the rail buttons in your sim model?

In my sim of my upcoming 54mm Hybrid record attempt RASAero and OR showed a significant difference when you include ALL the details. (14K OR versus 11K with RAS). With no rail buttons both packages showed about the same altitude.
 
A discussion of records would be interesting. It seems to be very inactive even after they dropped the altimeter requirements to something sane.

EX is practically unused, and the commercial haven't changed in forever it seems.

Why records are interesting, many of us do not live anywhere conducive to pursuing them. I think that is at least part of it.
 
Why records are interesting, many of us do not live anywhere conducive to pursuing them. I think that is at least part of it.

I agree 100%. The handicap division is kind of bleh, and Our waiver is 18K. Even with that I can't go for anything more than I records.

Gives some credit to Scott's idea of seperating based on body tube size. Would be similar to handicapped, but less specialized rockets I think. Have 38,54,76,98, and over 98mm as classes.
 
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So I finally figured out RASAero II and was able to run a sim on Do using 2 x H255 motors.

RASAero projected 18,117 feet in altitude and a max. velocity of Mach 2.01
By comparison Open Rocket projected 18,239' at Mach 2.08

The altitude estimations differences are not significant, and the Mach differences are barely significant. Both pieces of software have their strengths and weaknesses.

Again, I do not have any real experience in this department. I only have read "stuff" on the internet... I would be interested to see what your 100K rocket sims out to in both respective programs... If what I have read is true, there will be a clear discrepancy.
 
I would also strongly suggest using RAS Aero. I've used it for all my high performance flights and have always been easily within 5%, and after the first flight I can get the second to within 2%.

Edward
 
I would also strongly suggest using RAS Aero. I've used it for all my high performance flights and have always been easily within 5%, and after the first flight I can get the second to within 2%.

Edward

The 100K scenarios between OR and RASAero are close when you look at OR's projection without launch site info and Aero's launch site info included. However when the launch site info is included in OR, the OR altitude estimate is about 15% higher.

In the "Re" sim, I think RASAero is completely and totally wrong. IN the RASA sim, the sustainer achieves mach .95 and stays at that speed for 1.47 seconds. That is not possible for a rocket that is under thrust. In the OR sim, it continues to gain speed until about the last 2 seconds of thust when it starts to slow down, which is consistent for a longburn motor.

These are current simmed altitudes with launch site data included. Launch site Altitude is based on Google Earth estimates.

OR v RASA.jpg
 
The 100K scenarios between OR and RASAero are close when you look at OR's projection without launch site info and Aero's launch site info included. However when the launch site info is included in OR, the OR altitude estimate is about 15% higher.

In the "Re" sim, I think RASAero is completely and totally wrong. IN the RASA sim, the sustainer achieves mach .95 and stays at that speed for 1.47 seconds. That is not possible for a rocket that is under thrust. In the OR sim, it continues to gain speed until about the last 2 seconds of thust when it starts to slow down, which is consistent for a longburn motor.

These are current simmed altitudes with launch site data included. Launch site Altitude is based on Google Earth estimates.

View attachment 294160

Why do you say it's not possible for a rocket that's under thrust to reach 0.95 Mach and plateau there?
 
The 100K scenarios between OR and RASAero are close when you look at OR's projection without launch site info and Aero's launch site info included. However when the launch site info is included in OR, the OR altitude estimate is about 15% higher.

In the "Re" sim, I think RASAero is completely and totally wrong. IN the RASA sim, the sustainer achieves mach .95 and stays at that speed for 1.47 seconds. That is not possible for a rocket that is under thrust. In the OR sim, it continues to gain speed until about the last 2 seconds of thust when it starts to slow down, which is consistent for a longburn motor.

These are current simmed altitudes with launch site data included. Launch site Altitude is based on Google Earth estimates.

View attachment 294160
I think your Re sim set is comparing apples and oranges. I would look at the switch settings for your Re sim on RASAero and redo the sim as it is very different than the Do and Mi sim sets that have reasonable agreement.

I believe that RASAero does a better job handling Cd with RASAero predicting a higher apogee with the smaller motors in the Do data set and RASAero predicting a lower apogee in the higher Mach Mi data set.

I'm certain you will find an error somewhere.

To answer the generic question: can you have a thrust limited velocity? Absolutely. It happens all the time in auto, plane and boat racing:thrust = aerodynamic drag(f(v)^2) + gravity loss Mg. I believe you will find the max velocity is proportional to V^3 because you have to have the power to accelerate to get there.
 
I think your Re sim set is comparing apples and oranges. I would look at the switch settings for your Re sim on RASAero and redo the sim as it is very different than the Do and Mi sim sets that have reasonable agreement.

I agree on Do and Mi. Very concerned about Re, because it's one thing to kiss a waiver...it's another to obliterate it. I would not fly that rocket at full power anyway at Potter because there is a 20,000' call ahead waiver, but I have flown the motors in Re often and I know they go a lot faster and higher. I'll throw up a couple more comparisons of motor variations on Re. Almost all of them show a Mach .99 peak... even with a K2045 boosting a J530. Something is wrong with the Re sim, and it would be great if someone far more familiar with the software could shed some light on what I am doing wrong.
 
Why do you say it's not possible for a rocket that's under thrust to reach 0.95 Mach and plateau there?

I didn't mean to imply that it couldn't happen...but for almost 1.5 seconds? I find that a little hard to believe.
 
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