Phoenix Industries Tiny Booster! (Based on the GEM-46)

[-ctn-]

Hey everyone! I took a little break from modding/playing KSP and when I started playing again last night, I found that I could really use a tiny (0.625m) booster. Specifically because I wanted to replicate the Delta II rocket line.

Well, I made one up! I've finished the model and the texture - sadly I must leave for work... But soon it should be imported into the game and coded to work properly. I'm not sure how to balance the stats for it yet, but here it is!

As I said, it's small - 0.625m diameter and I believe around 5m tall.

Release Thread!

Edited October 6, 2015 by -ctn-

[hieywiey]

You should include this in your Phoenix pack! This fits quite well with it aesthetically and would make it easier for launching a Phoenix to resupply stuff, especially when you need that extra "umph!" when you load it up with heavy cargo! I like how the nozzle is angled, doesn't it make your rockets more stable if the boosters are angled like that?

[-ctn-]

Thanks! I may include it or keep it separate - not sure yet.

I'm going to make the exhaust nozzle a tiny bit bigger, it looks too small to my eyes even though it was to scale to the reference photos.

As for angled exhaust being more effective / stable - I'm not quite sure. I can imagine the angled thrust might work more efficiently in angling the kinetic energy "in and up", for lack of better term. To be honest I have no idea why they angled them. I'm going to look it up now...

[Gaalidas]

That and it's likely that having the heat being released from that nozzle pointed away from the rest of the hull would be beneficial to keeping things cool.

[-ctn-]

Ahhhh that makes a bit more sense. Having nine boosters radiating heat to the main engine is probably not a great idea.

[-ctn-]

Hey everyone! I kind of forgot about this part until recently, I started fresh and have it working (for the most part.)

I'm running into two issues - the particleFX for the engines is running constantly, even when the boosters are not activated. The second issue is that I'm getting the spinning rocket problem, just when the boosters are about empty, the entire rocket spins in the air. I'm not sure if this is a mass/drag issue due to quick rocket-building or if something with the booster part is causing it.

Any help with either problem would be greatly appreciated.

EDIT:

I ended up stealing the config for an existing stock SRB and modifying it for my own use - which fixed the issue.

Edited September 27, 2015 by -ctn-

[Kartoffelkuchen]

You probably misspelled the running effect name, check your config.

If you have 24 sides, you should rotate your collider by 12.5º on Z, to make the face the qttach point, not a rim between two faces. I had the same issue with my Delta II.

[-ctn-]

As far as I can see, there are no typos in the config. But I might be a little off on how to add particle effects to engines, I don't see a clear-cut tutorial anywhere.

[-ctn-]

Hurray! I tweaked the texture a tiny bit and played with the config. It now works as it should. The six boosters all together propelled this rocket to something like 600 m/s right at burnout, so maybe the thrust is a little high. I'll keep messing with it. But at least they work and look like how I wanted!

Also began work on the second booster for this mod pack - a tiny (0.625m) SRB intended to be used as a payload assist.

Edited September 27, 2015 by -ctn-

[-ctn-]

The rockets were spinning because of the angled thrustTransform. I had anticipated it being a problem so I went back to Unity and rotated the thrust to point straight down. The exhaust effects are still at a 10 degree angle to look correct but the actual thrust is straight down, which makes for more stable rocket building.

I also brought the thrust down and changed the exhaust effect on the payload assist booster so it's not so huge.

[Kartoffelkuchen]

Great! Really like the textures too

[Kerbal01]

There were designs that used a inline GEM series motor as a first stage for a small sat launcher. could you do this?

[-ctn-]

If I understand correctly, basically an in-line / stackable version of the booster as well as the radial mount version?

[Kerbal01]

yes, exactly.

[-ctn-]

I'll work on that when I get home. It will be stackable (without the nose cone) and the engine bell will be straight down, not angled.

Some quick math with its stats tells me that the maximum payload mass would be 4 tons with a TWR of around 1.3 on Kerbin, if you were to slap a satellite on top of the booster. Although you would only get 546 m/s of delta V, so you'd need an efficient second stage at the very least.

[-ctn-]

Some further brainstorming, I think I will try to add in a 2.5m solid booster, AKA the Titan IV-B booster for those that need insane lift requirements or those who use Outer Planets mods.