Scaling the Skies: Building a Blue Origin New Glenn Model Rocket at 1:90 scale

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Here is my latest project: a 1:90 scale model of the Blue Origin New Glenn rocket.

Named after astronaut John Glenn, the New Glenn is an advanced orbital launch vehicle designed for both commercial and government missions. The New Glenn features a reusable 1st stage like the SpaceX Falcon9 and has an impressive payload capacity of almost twice the capacity for Low Earth Orbit (LEO) and fifty percent more capacity for Geostationary Transfer Orbit (GTO) than the Falcon 9.

The New Glenn's first stage is powered by seven BE-4 engines and is designed to be reusable, landing vertically like the Falcon 9. Its massive size and capacity are designed to take heavier payloads into space, making it a game-changer in the space launch industry. The second stage is equipped with two BE-3U engines, providing the necessary thrust to deliver payloads to their intended orbits. A three-stage variant of the New Glenn rocket is also planned. This would provide capability for beyond LEO and GTO missions.

New Glen Wiki page
Official Blue Origin New Glenn website




This is how the New Glenn compares to other rockets.


As with my previous builds, the goals of this project are ambitious:

• Motor configuration matching the real New Glenn:
  • 7 motors in the 1st stage: 6 D12-0 motors and a center E12-0 for the initial design, with plans to develop a version using 24mm composite motors.
  • 2 motors in the 2nd stage.
  • 1 motor in the 3rd stage.
• Ignition system:
  • Use quick fuse to ignite the 6 D12 motors from the electrical ignition of the center E12-0 motor. Similar to how I have done ignition on my SpaceX Falcon 9 and Falcon Heavy projects.
  • Use the ejection charge from the previous stage to ignite the next stage, with plans to develop a version using electronic ignition for the 2nd and 3rd stages.
• Stabilization:
  • No artificial fins. Using Engine-Driven Gas-Dynamic Stabilization based on Tim's article from Apogee Rockets.
• Recovery system:
  • Rear ejection for first stage and (later) second stage recovery.
  • The 3rd stage will be developed after the two-stage version is operational, using the same techniques.
• Modular design: No glue™, so parts can be replaced as needed.
  • Adhesive paper “skins” will be used to hold all of the rocket body parts together.
  • Snap-in parts that work with the “skins” for ease of assembly.
• Aesthetic details:
  • The adhesive paper “skins” can be printed with logos and other scale details.
  • Working landing legs that extend for (an attempt at) upright recovery of the 1st stage.

Here's my first draft of the rocket body:


The flared skit will be used to create the air intake for Engine-Driven Gas-Dynamic Stabilization.

 

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For 2nd stage ignition:

Lessons learned from previous multistage projects. I'm including a tube to transmit the ejection charge from the 1st stage to the 2nd stage.

 

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Here are some details about the flip-out fin design for the 2nd stage.


This is the lower section.


This photo shows \the upper section which inserts into the 3" body tube of the 2nd stage. Note the hole you see in the top of the flip out fin assembly is an access hole for a screwdriver to attach the two parts together. It is hidden by the 3" thin wall body tube that goes over this part.


When the 2nd stage is mounted on top of the 1st stage the flip out fins fit inside the top section of the 1st stage:


The fist print always reveals bugs like the 1mm gap between the 1st stage and 2nd stage motor




Meanwhile the part that fits inside the 1st stage 3" body tube to direct the ejection charge to the 2nd stage looks like this.



The holes in the centering rings are designed to let the pressure from the ejection charge escape down the 1st stage body tube so the 2nd stage does not pop off like a champagne cork. There also will be additional holes at the top of the 1st stage for this purpose.


Here the center tube is mounted inside the 1st stage 3" body tube. The centering ring needs to be far enough inside so as not to interfere with the couplings to the bottom and top 3D printed parts.


The top of the motor looks like this. A BT-20 tube for the ejection charge from the E12-0 motor:




The BT-50 tube that carries the ejection charge to the 2nd stage fits over the BT-20 tube mounted directly above the E12-0 motor:



That black tape is another bug. I needed to increase the OD of the coupler which I did after this photo was taken.

 

[pugachu]

Cool project,

Will this be 'gap staging', or will the top be electronically activated? It looks like gap staging, but that's an awful big distance for the burning booster motor fragments to get to the upper stage to ensure ignition.

 

[ReynoldsSlumber]

Others can speak to gap staging distance, but in terms of how the upper stage lights, this NARAM R&D video presentation showed pretty conclusively that ignition is via the burn-through fireball radiating thermal energy rather than via a flaming solid piece of black powder making physical contact inside the upper stage nozzle.

 

[Switch]

Cool project,

Will this be 'gap staging', or will the top be electronically activated? It looks like gap staging, but that's an awful big distance for the burning booster motor fragments to get to the upper stage to ensure ignition.

My plan is to do 'gap staging' until I have the 1st stage working since I have a fair amount of experience with 'gap staging' with my Falcon 9 and Falcon Heavy projects. But I plan to use this New Glenn to explore electronic staging since the larger size will make that easier to achieve.

 

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Motor mounts and motors look something like this:





The D12-0 motors can just blow out with streamers but the mount I made can use set screws to hold them in place too. If D12-PT existed I would use those but this way I'm not making any modifications to the motors themselves.



The red centering ring is in contact with the 1st stage body to carry the force of the motors. I don't trust the small collar of the bottom centering ring to carry that much force.


Here is a photo before the collar is glued into place.


Here is a photo after the collar is glued into place.


That collar was an after thought that will be part of the print of this section going forward.

I've also spent some time with RockSim but I don't have any way to model the Engine-Driven Gas-Dynamic Stabilization. The best I can do is add weight where the 3D printed parts are and get a sense for how small the fins would need to be if I had them. I'm thinking about adding a mount for fins and then making them smaller and smaller with successive launches. But there's nothing like saying "to hell with it" and letting it fly as intended. The current center of pressure is about 133mm (13") from the bottom of the rocket (about 10mm higher than shown below).

There is also no way to model "flip out fins" so I did my best and need to just ignore what happens after MECO.


The attached RockSim file is just a hack for the record. I could not find an RockSim file online so I made this from scratch.

 

[bad_idea]

If D12-PT existed I would use those but this way I'm not making any modifications to the motors themselves.

Estes D11-P. Hasn't been made in a while but still available a few places, such as Jonrocket and AMW.

As an aside, I'm sure you know, but others thinking of cloning your setup might not: better nail the ignition of that center motor.

 

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Thanks for the tip on the D11-P.

As far as ignition goes, that was a bigger problem with my Falcon Heavy project where I needed to nail the ignition of the center motors for the center core and two boosters. I solved that by using RSignitors36-10 from https://rocket.supplies/. But for my Falcon 9 which is a 9 cluster, Estes Igniters have worked fine and that's what I plan to use on this project.

 

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Version 1.1 under construction with a tight deadline of tomorrow night before we head out to the launch site over the weekend.

My primary goal on my v1.1 build is to develop "snap-in" versions of the external fins. This makes the application of adhesive vinyl paper "skins" really easy since there are no parts protruding from the body tubes. The skins roll on the tubes and only require cuts where the parts snap in.

For the lower section the part looks like this:


and the "wings" look like this:


This shows the "wings" snapped into place




I decided to include fins on my early versions of this model on the bottom skirt:


These are very simple and design to snap into place. And I can trim them larger or to zero over successive successful flights


Here you can see the bottom section of the New Glenn with the fin slots.


I'm also now printing the air-intake part that transitions from the bottom skirt to the 3" body tube as it's own part:


This will allow me to iterate the size of the holes for Engine-Driven Gas-Dynamic Stabilization separate from the other parts.

The completed V2 body assembly looks like this:


Similarly the fins on the top of the 1st stage are now "snap-in" parts





I'm really excited to get these rockets ready to fly next week. There's still so much to do. Stay tuned...

 

[KenECoyote]

GDS? Subscribed!

 

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11:27pm and I'm too exhausted to do more than post a few photos.

Cluster with quick fuse. I'm using a new product for the fuse with is 10x faster than the cannon fuse I used before. High speed photography of the cluster ignition on my Falcon Heavy and Falcon 9 launches reveled that the motors ignited by the fuses did not ignite until the rocket was almost at the end of the launch rail. The new fuse should remedy that.


Application of vinyl printed skins



Skins before cutouts for snap in parts.


holes cut out:


Parts snaped in


A mistake I made that required Rocket Surgery™ to correct.


Finished Rocket






I'll post more details and launch results if I have them in two weeks.

 

[bad_idea]

Beautiful build!

 

[pugachu]

Best of luck on your flight!

 

[Daddyisabar]

Depending on how Dark Side you want to go you can put a pinch or modicum of BP on top of your red lable motors to enhance performance. You can also plug them with a nice doling of epoxy if no release of heat needed. It will slightly increase performance as well. Fuse ignition rocks! GDS rocks!

Just like the Level Three Navigator said in that silly version of Dune. "I see plans within plans. I did not say this. I am not here." Long live THE CODE. 0-0-0

 

[ljwilley]

Can't wait to see what happens!

 

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Here is my 1st version of the New Glenn on the pad. I don't have a video of the flight but it was not stable and tumbled. The 2nd stage did not ignite and 1st stage recovery failed.


My 2nd model had slots for some very small fins which are barely visible on the pad.


Test flight #2 was stable but one of the D12-0 motors exploded, 1st stage recovery failed, and 2nd stage ignition also failed.

Here's the raw video I took from a handful of locations.


All 7 motors in the 1st stage ignited on both rockets. The 2nd stage did not ignite and 1st stage recovery failed on both rockets. I suspect that the holes for the ejection charge are too small causing the 2nd stage to pop like a champagne cork before the gap ignition had a chance to work. I'm super excited with my progress on these first two launches. I plan to enlarge the holes on the engine driven gas intake and enlarge the ejection gas holes on the 1st stage on my next flights.

 

[ljwilley]

Here is my 1st version of the New Glenn on the pad. I don't have a video of the flight but it was not stable and tumbled. The 2nd stage did not ignite and 1st stage recovery failed.
View attachment 681450

My 2nd model had slots for some very small fins which are barely visible on the pad.
View attachment 681451

Test flight #2 was stable but one of the D12-0 motors exploded, 1st stage recovery failed, and 2nd stage ignition also failed.

Here's the raw video I took from a handful of locations.


All 7 motors in the 1st stage ignited on both rockets. The 2nd stage did not ignite and 1st stage recovery failed on both rockets. I suspect that the holes for the ejection charge are too small causing the 2nd stage to pop like a champagne cork before the gap ignition had a chance to work. I'm super excited with my progress on these first two launches. I plan to enlarge the holes on the engine driven gas intake and enlarge the ejection gas holes on the 1st stage on my next flights.

Nice footage. Glad that the rocket survived and you are going to try again!

 

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Nice footage. Glad that the rocket survived and you are going to try again!

Rocket survived? LOL. Rocket parts survived...

 

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Updated Video


Begin analysis of broken parts:



And an important discovery about the fuse I've been using to hot start the 2nd stage. It only lights from the end! I had always assumed it ignited anywhere along its length. But I did a test today that proved otherwise. I held a Bic™ lighter midway on the fuse until it caught fire & then didn't light. So the whole time I've been thinking that a longer fuse provided more surface arear to ignite from the ejection charge when in reality I was just moving the end of the fuse closer to the ejection charge. What I really need to to is spike the fuse with Quick Dip



I'm currently rebuilding for next club launch but here in California that might be months away.

 

[ReynoldsSlumber]

Impressive full cluster ignition, that thing got off the pad in a jiffy. Really cool ejector-style stabilization! Very innovative concept from that paper, and neat that you incorporated the intake vents into the conical transition section. Sorry about the pile driver finish, oof.

I'm a little confused by the terminology of the "ejection charge" from the booster igniting the upper stage. Surely you're referring to booster engine burn-through on a 0-delay motor...

 

[Daddyisabar]

Welcome the The School of Hard Knocks.!

 

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Impressive full cluster ignition, that thing got off the pad in a jiffy. Really cool ejector-style stabilization! Very innovative concept from that paper, and neat that you incorporated the intake vents into the conical transition section. Sorry about the pile driver finish, oof.

I'm a little confused by the terminology of the "ejection charge" from the booster igniting the upper stage. Surely you're referring to booster engine burn-through on a 0-delay motor...

Yes, the center E12-0 motor is supposed to both ignite the 2nd stage D12-3 and cause the motor assembly to eject out the back of the 1st stage for rear ejection recovery.

 

[Daddyisabar]

Yes, the center E12-0 motor is supposed to both ignite the 2nd stage D12-3 and cause the motor assembly to eject out the back of the 1st stage for rear ejection recovery.

Sounds like you may need some dark side techniques to fly the rockets you love. Shhhh! Say nothing...I know nothing!

 

[ReynoldsSlumber]

Yes, the center E12-0 motor is supposed to both ignite the 2nd stage D12-3 and cause the motor assembly to eject out the back of the 1st stage for rear ejection recovery.

Got it. Hmm, that might be asking the booster center motor to do too many things, and all at once. Humble suggestion, though I imagine you've thought through something like this already: Use the E12-0 booster center motor burn-through only to light the D12-3 upper stage motor, via a stuffer tube connecting the two that's fully sealed except for vent holes just below the upper stage motor, with larger holes in the centering rings and/or outer body tube as a pressure pathway to the outside. (Mentioning "fully sealed" because it's not clear from the photos whether the stuffer tube BT-20/BT-50 connections have centering rings to seal to each other.) Rely on upper stage motor ignition to separate the stages. And perhaps make some of the booster side motors be D12-3s in order to deploy parachute(s)? If that delay is short enough.

Alternative suggestion on booster recovery deployment: split the booster outer tube like a clamshell, such that the upper stage holds it together. That way, when the stages separate, the booster recovery system would deploy on its own, no need for booster side motor ejection charges etc.

 

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Note: earlier I mentioned boosters by mistake. My Falcon Heavy has boosters. This New Glenn has no boosters, just a 1st stage core and 2nd stage.

The tube to transmit the ejection charge has centering rings with holes to allow air and hot gases from the motors to move throughout the 1st stage body tube. I doubled the size and number of holes at the top of the 1st stage body to allow air to escape when the ejection charge ignites. Note the 1st stage motors eject out the back but the tube to transmit the ejection charge does not eject.

My next launch will include a static test of the 1st stage to observe the effectiveness of the holes at the top of the 1st stage to allow cold air to escape and to make sure new modifications to the 2nd stage ignition work.

 

[OzHybrid]

Lovely job. There's a lot of good ideas here for people to learn from and advance their rocketry skills. Disappointing it wasn't successful first time, but I'm confident you'll make it work.
Are the stl files going to be available?

 

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Lovely job. There's a lot of good ideas here for people to learn from and advance their rocketry skills. Disappointing it wasn't successful first time, but I'm confident you'll make it work.
Are the stl files going to be available?

Thanks for the kind words. I haven't given any thought to stl files. Right now my focus is building a scale model rocket that actually works.

I did 4 test flights at Snow Ranch last Sunday:

Flight test #1: 7 cluster, single stage test of GDS with larger air intake holes than on the 1st two flights.
6 Estes D11-PT + E12-0



View attachment IMG_3213.mov
Although the rocket tumbled recovery via nose cone ejection worked. 6 our of 7 motors also worked.



Flight test #2: 2nd stage only GDS (idea was to reduce the complexity of flip out fins)
Motor: Estes D12-3
View attachment New Glenn 2nd stage GDS.mp4
2nd stage tumbled.


Flight test #3: Static fire of 1st stage, 2nd stage with flip out fins
Motor: Estes D12-3


View attachment 1st stage static 2nd stage flip out fins.mp4
2nd stage was ignited from the ejection charge in the 1st stage and 2nd stage recovery worked.

Flight test #4: 7 cluster, single stage test of GDS with smaller air intake holes plus small fins (same as flight #2 in Death Valley).
6 Estes D11-PT + E12-0
View attachment New Glenn 7 cluster 2 stage with fins.mp4
7 out of 7 motors ignited in the 1st stage but rear ejection did not work (fortunately only the skirt was cracked). 2nd stage ignition and recovery worked but a flip-out fin broke resulting in a cork-screw flight of the 2nd stage.




On Test Flight 4 the BT-50 tubes carried the ejection charge to the 2nd stage and survived intact.



On Test flight 3 (static 1st stage) the BT-50 tube was completely destroyed

I think the reason the bottom of the BT-50 tube burned test #3 (static test) but not on test #4 (air start test) is that the motor ejected on the static test but not on the air start test. So on the air start test the edge of the BT-50 tube was never exposed to the ejection charge. I think the reason the top of the BT-50 tube burned on the static test is that the D12-3 motor had time to burn against the restrained first stage, where as the ignition of the 2nd stage in the air start would have pushed the 1st stage away as pressure mounted.


In conclusion, I feel really confident in the use of the BT-50 tube to ensure ignition of the 2nd stage. I should also note that the quick fuse I put in the 2nd stage motor is long enough to extend some distance inside the BT-50 tube and I use an X-ACTO knife to split the last three inches of the fuse to expose the combustible fuse material to the ejection charge. I did the same thing with my Falcon Heavy last weekend and the 2nd stage. The test of GDS on the 2nd stage convinced me to stick with flip out fins for now. Also, I learned from a test of GDS on my SLS project that once the motor cuts out, GDS stops providing stability. So GDS is best suited for boosters that separate at BECO or in the 1st stage of a 2 stage rocket like the New Glenn.

My next step in the development of GDS on the 1st stage of the New Glenn will be to recess the motors deeper up into the skirt. I also now know that there is no need for a delay charge in the center motor when testing the single stage version since the rocket will tumble once it loses thrust. I think the problem with rear ejection observed in flight test #4 had two causes: 1) the fit of the motor is a bit tight and 2) I didn't make a slot for the Kevlar™ string that runs from the outside of the rocket to the recovery chute. Fortunately the broken skirts are easy to repair and the modifications described above are pretty straightforward. So I should have another set of New Glenn rockets ready to test at the next launch.