Apogee X-15 Rocket Kit - Side Eject?

[JSW]

Just received the Apogee X-15 rocket plane kit. Looks pretty awesome.

Thee only thing I want to change is to have some sort of side/top eject where it can come down hanging horizontally from the chute with the nose cone still attached.

The main worry is that this kit is fairly expensive to mess up - either by trying unsuccessfully build a side-eject - or by having a side-eject failure after launch.

Any thoughts or recommendations?

 

[kjohnson]

If you're worried about wrecking the kit, why not build a regular BT-80 rocket about the same size and test it out? That way you get to figure out how to fix any failure modes before you try it on the kit?

Here's a couple of things to consider- you will need a hole big enough for the right sized parachute in the side of the tube. You'll need to support that area so it doesn't look like there is a hatch, you'll want to make sure the parachute stays in place in the body under that hatch, and you'll have to eventually deal with the changes to the CG on the X-15..

kj

 

[JSW]

If you're worried about wrecking the kit, why not build a regular BT-80 rocket about the same size and test it out? That way you get to figure out how to fix any failure modes before you try it on the kit?

Here's a couple of things to consider- you will need a hole big enough for the right sized parachute in the side of the tube. You'll need to support that area so it doesn't look like there is a hatch, you'll want to make sure the parachute stays in place in the body under that hatch, and you'll have to eventually deal with the changes to the CG on the X-15..

kj

you're exactly right! need to set it up and test before implementing on the real thing.

rear eject also an option, although I've done a couple of those but want to try something else.

i have been searching around the forum for side-eject techniques,... found electronics/mechanical/compressed-air methods.

rather use the engine eject charge if at all possible. any thoughts or examples? engine eject burns a thin string that releases a spring-loaded hatch?

 

[afadeev]

Just received the Apogee X-15 rocket plane kit. Looks pretty awesome.

Thee only thing I want to change is to have some sort of side/top eject where it can come down hanging horizontally from the chute with the nose cone still attached.

The main worry is that this kit is fairly expensive to mess up - either by trying unsuccessfully build a side-eject - or by having a side-eject failure after launch.

Any thoughts or recommendations?

I remember a kit of two that achieve the above objective by having two (2) attachment points for recovery gear: one near the engine mount, and the second one routed externally and attached near the front end of the airframe tube.
It may have been one of the kits built for maximum flight duration competition.

The downside of that, however, is that your rocket will be drifting for way longer. Which can be a challenge around most fields.



https://www.apogeerockets.com/Rocke...odel-Rocket-Kits/International-Thermal-Sailor


I remember building that kit.
It worked, but the external recovery gear string tended to tangle up upon deployment. Even so, the extended hikes to recover the rocket had dissuaded me from trying something like this again.

YMMV,
a

 

[KenECoyote]

https://www.rocketryforum.com/threads/radical-rocketry-f-104-starfighter-build.177799/post-2423630

https://www.rocketryforum.com/threads/radical-rocketry-f-104-starfighter-build.177799/post-2423638

If you'd like to test, it's much simpler to just add a fishing line and second attachment point vs. creating a side ejection.

Personally, I'd look into strengthening the balsa wings and fins with CA and papering or replacing with thin lightweight ply.

 

[kuririn]

Thee only thing I want to change is to have some sort of side/top eject where it can come down hanging horizontally from the chute with the nose cone still attached.

https://www.rocketryforum.com/threads/lexxjet-flying-customizations.185804/#post-2572922
Simplest method, nothing complicated.
But coming down horizontally might expose the bottom rudder to landing damage.
Good luck.

 

[burkefj]

Just received the Apogee X-15 rocket plane kit. Looks pretty awesome.

Thee only thing I want to change is to have some sort of side/top eject where it can come down hanging horizontally from the chute with the nose cone still attached.

The main worry is that this kit is fairly expensive to mess up - either by trying unsuccessfully build a side-eject - or by having a side-eject failure after launch.

Any thoughts or recommendations?



View attachment 641416

What perceived problem are you trying to solve?

 

[Steven]

The Centuri SST Shuttle came down like this.

 

[JSW]

What perceived problem are you trying to solve?

No problem.

Preference is to have the plane come down still looking like a plane - nose cone intact. Just looking for ideas on how to make that happen.

I can probably rig up a side-eject on my own, but was hoping forum folks had done it before and I could "leverage" their experience and technique.

 

[kuririn]

Y harness with rear eject motor mount.
But the cg to cp position is so marginal that you are instructed to not even add an engine hook.
So you may need to add some nose weight to bring the cg back to its' stock position.

 

[KenECoyote]

Coming from someone who pr

No problem.

Preference is to have the plane come down still looking like a plane - nose cone intact. Just looking for ideas on how to make that happen.

I can probably rig up a side-eject on my own, but was hoping forum folks had done it before and I could "leverage" their experience and technique.

Coming from someone who prefers to do things differently, I'd say it's a lot more trouble and complication than it's worth.

Regardless, it would be very cool if you could achieve it.

So ask yourself how much do you want this? If it's a lot, then start on designing a test bed to try some things out first. This is what I'm currently doing with my HED Cannon.

Also note that the more you do things differently, the more complications and unexpected issues you'll come across. For me, I enjoy the challenge and the problem solving (most of the time ).

 

[KenECoyote]

Come to think of it, I have come across a few times where I read of rockets with side deploy chutes. Usually it's one with little space for a traditional av bay, like the V2 and X-15, but those were fairly big rockets from my recollection. Try searching it out.

 

[KenECoyote]

Come to think of it, I have come across a few times where I read of rockets with side deploy chutes. Usually it's one with little space for a traditional av bay, like the V2 and X-15, but those were fairly big rockets from my recollection. Try searching it out.

https://www.rocketryforum.com/search/597623/?q="Side+eject"&o=relevance

 

[JSW]

https://www.rocketryforum.com/search/597623/?q="Side+eject"&o=relevance

Thanks for the search link.

I definitely researched this forum with “side eject” and other search terms. Also did a Google search.

The forum search results show methods with timers or other electronics. I didn’t find any using engine eject? Or maybe I missed?

 

[JSW]

I appreciate everyone’s input.

Seems like too much of a hassle for what it’s worth - which is probably why I’m not finding any good examples using engine eject charge.

If I happen to experiment and come up with something - I’ll be sure to post it.

Thanks!

 

[WizardOfBoz]

If you're worried about wrecking the kit, why not build a regular BT-80 rocket about the same size and test it out? That way you get to figure out how to fix any failure modes before you try it on the kit?

Here's a couple of things to consider- you will need a hole big enough for the right sized parachute in the side of the tube. You'll need to support that area so it doesn't look like there is a hatch, you'll want to make sure the parachute stays in place in the body under that hatch, and you'll have to eventually deal with the changes to the CG on the X-15..

kj

Agree with all. Joe Barnard (BPS Space, on Youtube, no connection) recently launched a rocket with two cameras that were designed to flip out and take pictures of each other. It was a very powerful rocket (L motor IIRC) designed to go supersonic. It did. It spontaneously disassembled at altitude and speed. In the after-action analysis, Barnard speculated that the Mach 2 wind velocity sucked one of the pivoting cameras out where it caught the wind, causing rather spectacular damage. The camera, btw, was recovered, separate, after a mach 2 event and falling 4 km - and it worked!.

The point is, I'd make sure that any hatch I had 1) was forced closed by wind velocity and 2) had enough oomph to open when it needs to.

 

[Azamiryou]

I appreciate everyone’s input.

Seems like too much of a hassle for what it’s worth - which is probably why I’m not finding any good examples using engine eject charge.

If I happen to experiment and come up with something - I’ll be sure to post it.

Thanks!

I hope you do, and I look forward to seeing it. People doing things outside the norm makes the hobby more interesting! And whether or not you succeed, you're bound to learn something and have fun.

(I agree with the advice to use a simple rocket for figuring it out, though.)

 

[kjohnson]

Here's an old example from the hey day of NAR competition where the model was designed to open up the body tube to allow for a bigger recovery device. Not quite the same thing, but gives some ideas.

https://oldrocketplans.com/cmr.htm

kj