Two-stage HPR design build

[SteelyEyed]

I've been thinking about doing an HPR 2-Stager for a long time. I've completed the "draft" design in RS9. I say "draft" because I'm sure it will evolve a bit as the build progresses. I'm going to start by building the sustainer. I need some help from my TRF buddies, so please chime in here. In particular, I'm not sure how I want to couple the booster to the sustainer. And I'm thinking drag separation for staging (but I'm not tied strongly to any single approach). I've never done this before, nor have I begun searching the forums for techniques... So, if anyone can point me to useful threads (I'm sure I will pick up a thing or two from the dixontj93060 thread that is currently in the works), or offer experienced, sage advice please do so. I would also like some advice on avionics and sustainer ignition. In general, I don't know what I'm doing and I'm looking for help!

Once again, I just cannot bring myself to build a simple 3 or 4 fin design for the sustainer (or the booster for that matter). So, I've added some unique features to make it interesting (going for that "cool, futuristic surface-to-air, high-altitude, hyper-sonic, scram-jet powered sustainer" look). The sustainer will be 3" OD airframe with a 54 mm MMT, and the booster a 4" OD with a 54 mm MMT (Bluetube and G10 fins throughout).

Will post some RS9 images tomorrow...

Steely

Later downstream edit: As I progressed on the project I had to switch the upper stage MMT from 54 to 38mm. The 54 mm MMT did not allow enough space to utilize the stage coupling method that I settled on.

Edit #2: I also decided to do the booster fins out of 3/16" plywood, because they are easier to fabricate (including bevels) than fiberglass and don't add as much weight at the "wrong" of this bird.

 

[blackjack2564]

I for one, am really looking forward to THIS!

Bring it one.

 

[redsox15]

I for one, am really looking forward to THIS!

I second that!


Matt

 

[Wayco]

Definitely subscribing to this post! I'm working on designing an upscale Dyna-Star Rip Roar and need ideas on electronics for staging and air starts. I'm also monitoring dixontj's thread, I like his build too.

 

[SteelyEyed]

Okay, here are some images of the sustainer from RS9. I have a working title of "Checkmate" for the sustainer and "Gravedigger" for the booster. I need to think up a final name and am open for suggestions...

This design has four aft fins, two of which have "scram-jet" intakes (a bit similar to my Diamondback design). And there are two forward canards (that look cool IMHO, and serve to offset the aerodynamic asymmetry from the scram-jet tubes). Motor retention will be accomplished with a GLR Quik-loc retainer. The way I have it modeled in RS9 right now the sustainer is a single deploy, zipperless baffle design, but that will be reworked to a dual-deploy configuration.

 

[SteelyEyed]

And here are a few more images, some of which show the two-stage configuration. The booster design includes two transitions (I hope to fit the booster electronics in the forward transition). The booster fins (of which there are 6) span the aft transition. In effect, the aft transition serves a bit like a boat-tail; it's there just to add a unique design feature (cause I like it)...

It's likely that I will have to lengthen the sustainer airframe to accomodate the DD setup and an Av-bay and I may lengthen the booster airframe to accomodate a larger (longer) motor, but these images capture the near final look of the design. I picture it in my head as a modern Nike Ajax-like design. Comments?

 

[loopy]

Holy crapola!!!! Very cool! I like it! And boat tails are just awesome. What's the time frame for this thing?

 

[jms]

As always Bret, your designs are awesome.

 

[sodmeister]

As usual ,the design is a thing of beauty ,not just another 3FNC ........and that I like !!!!

Too bad you`re not a kit manufacturer !

Please continue ,I`ll be watching


Paul T

 

[SteelyEyed]

I for one, am really looking forward to THIS!

Bring it one.

I second that!

Matt

Definitely subscribing to this post!

I appreciate the positive feedback gentlemen. I hope you all enjoy the build as much as I do...

 

[SteelyEyed]

Holy crapola!!!! Very cool! I like it! And boat tails are just awesome. What's the time frame for this thing?

Loopy, glad you like it. The time frame? This is planned as a "winter" project. I have the sustainer airframe pieces and MMT cut to length. I have the nose cone, centering rings, fins, and retainer. Still have more parts to purchase or fabricate. So, it is progressing... slowly. I hope to have it ready to fly next spring, maybe at FITS in May.

As always Bret, your designs are awesome.

Thanks jms.

As usual ,the design is a thing of beauty ,not just another 3FNC ........and that I like !!!!

Too bad you`re not a kit manufacturer !

Please continue ,I`ll be watching

Paul T

Thanks Paul, sounds like we have similar taste in rocket designs. Four of my designs are available from three manufactures (and others are in the works). But, more often than not, my designs are too complex for kit makers to bring to market at a price point that will offer a return for thier effort. For the record, I am always willing to offer my designs to maunfacturers. All I ask in return is to be acknowledged as the designer and to receive one free kit when they add it to their product line. I get my greatest satisfaction from this hobby (I've loved since 1972) when others build, fly, and enjoy my designs. Anything I can do to make the manufactures successful and contribute to the overall health of the hobby is also a joy for me.

 

[SteelyEyed]

I have given alot of thought to my electronics for this project. I recently (yesterday) learned about a product from Missile Works that is in beta testing. It is a four channel RC system that can be used to actuate flight events such as launching the rocket, igniting the second stage, and deploying the main, etc. Sounds like that would be a hoot to be controling flight events during the flight. From a safety perspective it would allow me to decide whether or not the flight trajectory is suitable for the upper stage to be ignited. And who wouldn't enjoy deploying the main on demand?

I talked to Jim Amos of Missile Works today and he plans to release the product this year. I requested pre-order placement today. I will be posting more on this item as information becomes available...

Bret

 

[[POW]Eagle159]

I have given alot of thought to my electronics for this project. I recently (yesterday) learned about a product from Missile Works that is in beta testing. It is a four channel RC system that can be used to actuate flight events such as launching the rocket, igniting the second stage, and deploying the main, etc. Sounds like that would be a hoot to be controling flight events during the flight. From a safety perspective it would allow me to decide whether or not the flight trajectory is suitable for the upper stage to be ignited. And who wouldn't enjoy deploying the main on demand?

I talked to Jim Amos of Missile Works today and he plans to release the product this year. I requested pre-order placement today. I will be posting more on this item as information becomes available...

Bret

The Remote Controlled rocket....NiCe!!!! Have the kids press the buttons when ready!


Next we need an interesting name for this project........:wink:

 

[sodmeister]

Bret ,we do indeed have much in common in missile design !

When it comes to being too complex to manufacture......I see it as a one off ,and that could be a good thing also.

As soon as I get some things off of the build table ,I plan on doing a few HP designs myself .

Please continue your build

Paul t

 

[SteelyEyed]

Next we need an interesting name for this project........:wink:

[POW]Eagle159,
I thought a little bit more about the name of this boosted bird. As I was designing it I envisioned a modern version of the Nike Ajax (a 2-stage surface-to-air missile). I have not yet come up with a final name, but I did think of a much better working title...

how 'bout -- "Reebok Comet" ?!? :rofl:

...think about it you will figure it out.

 

[SteelyEyed]

As I mentioned up front, this design is indeed evolving a bit. I decided to connect the booster to the sustainer using three 1/4 inch pins that will be protruding from the forward transition on the booster. The three pins will slide into three aluminum tubes that will be mounted in holes drilled through the three aft centering rings on the sustainer. As a result I had to reduce the sustainer MMT to a 38 mm size. With the 54 mm MMT, there just was not enough CR through which to mount the aluminum tubes described above.

I also converted the sustainer to a dual deployment configuration. Note that both the sustainer and the booster have been re-designed to be a zipperless baffle configuration (for when I fly them using motor ejection charge deployment). I plan to be able to fly the booster by itself, by replacing the forward transition with a payload bay and nose cone. The sustainer will, of course, be flyable as a single stage with dual or single deployment.

The new RS9 exported 2D image is shown below...

 

[SteelyEyed]

I received an email from Jim Amos (missileworks.com) yesterday providing me a look at the new WRC+ four channel wireless RC flight even controller. I'm really lookging forward to laying my hands on one of these. Pics attached...

 

[[POW]Eagle159]

I received an email from Jim Amos (missileworks.com) yesterday providing me a look at the new WRC+ four channel wireless RC flight even controller. I'm really lookging forward to laying my hands on one of these. Pics attached...

Press ALL the red buttons!!!

 

[SteelyEyed]

Press ALL the red buttons!!!

At this point I'm thinkin' I'll only be pressing 2 or 3 of the four red buttons. "One" to ignite the sustainer stage, "Two" for apogee drogue (but that might me difficult to see depending on the motor selection, so I will probably have an altimeter that will be set to deploy a drogue at apogee, leaving me the option to do nothing at apogee), and "Three" will be to deploy the main (although I will likely have the altimeter set to deploy the main at 300 ft as a backup).

Obviously, I will be doing lot's of ground testing to make sure I get it all working as intended...

 

[dixontj93060]

At this point I'm thinkin' I'll only be pressing 2 or 3 of the four red buttons. "One" to ignite the sustainer stage, "Two" for apogee drogue (but that might me difficult to see depending on the motor selection, so I will probably have an altimeter that will be set to deploy a drogue at apogee, leaving me the option to do nothing at apogee), and "Three" will be to deploy the main (although I will likely have the altimeter set to deploy the main at 300 ft as a backup).

Obviously, I will be doing lot's of ground testing to make sure I get it all working as intended...

You might consider having one control as a "lock out" to scrub sustainer ignition if something goes awry. This is the way I was considering using the old WRC in my two-stage rocket (Double Take), but in the end didn't have enough room in the 3" airframe.

 

[SteelyEyed]

You might consider having one control as a "lock out" to scrub sustainer ignition if something goes awry. This is the way I was considering using the old WRC in my two-stage rocket (Double Take), but in the end didn't have enough room in the 3" airframe.

That is an excellent suggestion. Since I have not layed my hands on one of these yet, I did not know that was an option. If there is an unused channel available, that would be the best way to utilize it.

I was thinking that if the flight was unstable or aimed in a "un-desired" direction after booster burnout, that I would simply NOT press the ignition function for the sustainer. It would be highly desirable when recovering the upper stage with a live igniter and avionics powered up to be able to "safe" the system. Thanks for the recommendation, I will look for that in the user's manual...

 

[dixontj93060]

I was thinking that if the flight was unstable or aimed in a "un-desired" direction after booster burnout, that I would simply NOT press the ignition function for the sustainer.

You may have better hand-eye coordination than I do, but I don't believe I could time the ignition correctly. My intention was to have a timer control the ignition, but have a switch/relay hold the initiator circuit closed through the ignition event, but release it to a normally open state within the first few seconds if warranted. Again after looking at the footprint of the old WRC, and realizing I couldn't fit it, I ended up not implementing it though.

 

[JimJarvis50]

At points in the past, I've toyed with the idea of the WRC approach for staging. I've never done it, so I can't speak from experience. However, I can imagine all sort of issues that would complicate the decision to push the button or not. One problem is that it is not always easy to know exactly what's going on with a flight. In the heat of the moment, time gets sort of compressed. There are a lot of things to keep an eye on, and you can't always see exactly what the orientation of the rocket is.

Although making staging decisions in real time would be pretty cool, my advice would be to do a few flights first where you let the electronics make those decisions for you (or rather, where you program the flight to have the sequence go according to your plan). With the electronics packages that are available, you can verify that the flight is nominal as a criteria for lighting the second stage and you can pick the speed at which you want the motor to ignite. I think more is learned about how the flight should go with this approach.

In any case, I'm glad to see more people doing staging. I like watching them and doing them myself.

Jim

 

[SteelyEyed]

At points in the past, I've toyed with the idea of the WRC approach for staging. I've never done it, so I can't speak from experience. However, I can imagine all sort of issues that would complicate the decision to push the button or not. One problem is that it is not always easy to know exactly what's going on with a flight. In the heat of the moment, time gets sort of compressed. There are a lot of things to keep an eye on, and you can't always see exactly what the orientation of the rocket is.

Although making staging decisions in real time would be pretty cool, my advice would be to do a few flights first where you let the electronics make those decisions for you (or rather, where you program the flight to have the sequence go according to your plan). With the electronics packages that are available, you can verify that the flight is nominal as a criteria for lighting the second stage and you can pick the speed at which you want the motor to ignite. I think more is learned about how the flight should go with this approach.

In any case, I'm glad to see more people doing staging. I like watching them and doing them myself.

Jim

I've watched others utilize RC staging and it looks like fun. A particularly impressive one was Terry Lehright's maiden flight of his two stage (M to M) Nuclear Sledgehammer. He made it look easy, delaying about two seconds following burnout before the sustainer lit. Kent Burnett of GLR tells me RC staging is the only way to fly. Can't wait to give it a try...

 

[SteelyEyed]

I've been collecting and fabricating a few pieces for this project and construction has begun.

 

[SteelyEyed]

I decided to start the booster assembly first because the sustainer is still evolving a bit after I converted it to DD. I'm trying to decide where to put the av-bay, laundry, and Garmin Astro DC30. In this shot you can see I've attched the Quick-Loc retainer on the 54 mm MMT, cut the booster fins, assembled the boat tail, and cut the fin slots in it...

 

[Stable1]

I decided to start the booster assembly first because the sustainer is still evolving a bit after I converted it to DD. I'm trying to decide where to put the av-bay, laundry, and Garmin Astro DC30. In this shot you can see I've attched the Quick-Loc retainer on the 54 mm MMT, cut the booster fins, assembled the boat tail, and cut the fin slots in it...

Looks like a great build! Who's transitions are you using -- they look perfect for a project I'm thinking about

 

[Aksrockets]

Wow. You build awesome stuff.

 

[SteelyEyed]

Looks like a great build! Who's transitions are you using -- they look perfect for a project I'm thinking about

They are PML transitions and work well with Bluetube. I cannot remember the vendor that I ordered them from. They've been in my "big box-o-parts" for a few years. I had been planning on using one of them to build another "Nuclear Crowbar" https://www.rocketryforumarchive.com/showthread.php?t=35362&highlight=nuclear+crowbar(the first one dug a four foot trench in a cornfield in Michigan :y.

 

[sodmeister]

Hey Bret ,that`s what I`m talking about......PARTS ,PARTS and more PARTS......

Now it gets interesting.

You have my full and undevided attention.

Don`t you just love BlueTube !!


Cheers

Paul T