AKS HK-203G 'Tri-Fighter III' SSTO

[panzer1b]

Well after a long time of trial and error messing with optimal fuel loads, changing teh aerodynamics which im still not that satisfied with, i think i have managed to come up with something that im actually rather proud of.

The HK-203G "Tri-Fighter III" long range combat interceptor.

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craft file below:

http://www./download/5akcl8psat4y7v2/zAKS+HK-203G+%27Tri-Fighter+III%27.craft#39;Tri-Fighter_III'.craft

As for the basics: 2 activates lower rapiers, 3 activates upper rapier, 4 toggles the nuke toggles space mode on the rapiers and toggles the 2 cone intakes shut, and 5 toggles the 16 ram intakes.

All in all, it has extremely good range for something that started out as a short range point defense interceptor (the original tri-fighter I was just a FLT-800 surrounded by 3 FLT-400s with a aerospike on each of the 400 tanks. It was rather pitiful in terms of range, but it did work rather well when all it was suppose to do was undock from a carrier, fly in, shoot its 3 missiles at a target, and gun it back to the carrier before whats left of enemy retaliated. My second design, the tri-fighter II was more or less a similar layout, but redone to not be fully symmetrical (the 1st one was a bloody pain to figure out what direction it was facing due to 100% 3 way symmetry). It was somewhat of a half mix between my original and a BSG viper i saw somewhere on the forums, it had 3 turbojets and 3 909s, giving it OK range, but it was still poor outside of atmo. My final one is still based on its predecessors, but overhauled to stick a nuke on board supplemented by 3 jets, although the latest one uses rapiers as i prefer to have worse atmospheric performance, in exchange for the ability to gun it very quickly when needed using the thrust from 3 rapiers and a nuke in space (gotta love the effects with the nuke clipped in between the 3 rapiers, so much blue flames!). Overall i think it came out good in both the looks department and surprisingly good range and acceleration (3 rapiers pushing 10-15tons is gonna make u speed up very very fast in rocket mode).

ISP with rapiers is approximately 1800 once you leave atmo (fully fueled is like 2500ish with rapiers only running), and with just the nuke (which is your main space engine), its above 4000, enough to get to duna, land on duna, and get back in LDO (low duna orbit) without refueling at all or taking advantage of any special tactics like say slingshots ect, although i did aerobrake at duna somewhat so that did cut down the fuel needs (im assuming aerobraking is obvious enough that most people would take advantage of this to slow yourself down). No cheats of any sort were used, and everything was bone stockm, although it is technically a airhogger with 18 intakes, and has alot of clipped parts (i didnt use the alt-f12 cheat, as that actually makes it impossible to place anything, bug or whatnot, but it does clip parts visually even if teh game says its ok). I have done these tests to verify that it does actually have somewhat respectable range for a primarily aesthetic SSTO: fly to mun, land and return to KSC, fly to minmus, land, and return to KSC, fly to duna, land, and get back in stable orbit (albeit rather low orbit). The mun trip was also done with alot of rapier, since i mistimed the braking and had like 400m/s left at like ground level, so i wasted alot of potential fuel with that burn. For kerbin/mun/minmus stuff, it has plenty of fuel, and you can actually afford to be somewhat inefficient or like me use rapiers for mun landing when you mistime the brake burn and risk ending up making a new crater.

The optimal ascent profile i found is to climb to 20k as quickly as you can, then slowly level out, flying relatively straight at 30km, maximize speed, and once you stop gaining it, increase altitude gradually to 45km minimum while gaining as much speed as possible on the rapier jet mode, this means manage intakes (close the rams with 5 key at altitudes below 15km as they just add needless drag), throttle control above 30km, and shut down all but the top engine (2 key will kill the bottom engines) above 45km as the rest of the engines are unable to work, so why give yourself off center thrust? Switch to nuke above 50km, although i have found it still is OK to go nuke at 40km, just a little inefficient in terms of fuel use (its faster to get orbit nuking at 40km, so if you are going to fuel in orbit anyways, might as well do that, or use some closed cycle when really fuel isnt an issue). Keep the rapiers off when using nuke, as they will switch to rocket mode, which is really only intended for emergency boosts or combat (assuming DMP fixes its massive sync bugs and makes hitting someone thats not just sitting perfectly still possible). Rapier rockets do come in handy for braking on landings, although i still recommend avoiding their use at all outside of air breathing mode, since the ISP is so bad you are better off using LV909s (which are terrible themselves as ive tested on anything that isnt a extremely small/lightweight ship/probe).

Anyways as for changes that can be done to cater this to individual styles, the rapiers can be switched for turbojets, making ascent MUCH easier and less time consuming, with only the loss of the so called WEP (war emergency power) for landing/chasing people down. They can also be switched for the regular jets if low altitude is desirable (and the nuke can be ditched to save weight), although dont expect it to get in orbit then. Also, the nuke can be ditched if you only want to do kerbin orbit work or possibly get to mun/minmus (id guess perhaps 2000ish dV with the rapiers only once nuke is removed in space). Ive tried VTOL variants of this too, but that seems to be a little bit redundant as its low speed maneuverability is very good with any engine configuration, especially the regular jets. The plane gets more and more stable with speed increase, so while it is tough to turn on the spot at say 200+m/s, when going 100 or less, you can do a 180 and reverse direction rather easily, although only the regular jets let you fly circles around ksc and actually avoid every collision super easy.

Anyways, id like some feedback on this design, and perhaps some tips to increase the range, as right now the only way to reliably get more range is to go with droptanks or refuel somewhere, something that doesnt really make this a true self sustained SSTO. Also, please refrain from any critisisms regarding the clipper parts/airhogging, i know there is a subset of the KSP community that thinks such stuff is cheating, personally i consider it legit and use it to keep parts i dont want visible inside (a stack of 16 ram intakes isnt exactly pretty anywhere lol), and well, its just my style, i build for looks, then cram the internals with gear, while many others care more about things such as realism (not that stock ksp is realistic but thats another thread ).

Edited December 6, 2014 by panzer1b

[Prof. Endwalker]

Wow! That is one impressive and effecient craft! Imma have to download that later today. It is possible to go to-and-back Eve mission?

[Guest Space Cowboy]

Colonial TriFighter

[gGATORr]

Nice! Reminds me of a Viper from Battlestar Galactica