F02-class Evean Shuttles

[recursive_mouse]

For stock 1.43. However, KER / TimeControl / SCANSat is recommended to explore full potential. 

warning *Extreme* offsetting is used. 

.craft zip

 

F02 "Evean Infiltrator"

(Twin-Cycle Rocket / Nuclear SSTO)

 

Based on successful F02 prototype, the "Infiltrator" is specially made for Kerbin Spek-Ops operative. Took advantage from zipfuel technology, also fully equipped for a complete self-sufficient / extended long term mission. 

Spoiler

 

Comes with proper command pod, mobility enhancer, spacious docking bay, TCS/RTG/SPL, junior mining set. For more ease of life, drill been setup externally for better surface reach( worry not fighting with landing gears! ).

From atop Eve tallest moutain, the Infiltrator obtain stable Eve orbit like a casual walk( Suppose you did successful at taking off, that is. ), with 60-160 m/s dv budget left for room of error. When carrying zipfuel tanker in cargo bay, the SSTO is capable of travel everywhere, land everywhere,  return everywhere. It is also aethestically pleasing to fit KSO agents' elite status. 

( tanker not implemented in .craft file )

When rocket fuel are much drained, the Infiltrator is structurally sound and survive head-on Eve reentry. However landing is nemesis: it is optimized for full-loaded Eve ascending, so an empty plane is TOTALLY unstable. Mining on Gilly to keep minimum a quarter of rocket fuel before entry. 

 

User Instructions:

Spoiler

 

Take off Instruction:

Aim ONLY for most flat terrain atop Eve tallest mountain. Hands free and do not put any strain on landing gear, plane will take off by natural lift. When airborne immediately retract gears to reduce drag. 

 

Ascent profile:

Full throttle all the way, activate Nervs at 22~30km altitude. 

After taking off aim 25 degree above horizon until 35km.

At 35km prepare to flatten out. Should point to 20 degree exiting souposphere( 41-42km ). Pull down speed vector to 15 degree or lower, aim for 110~120km AP with 3 minute grace time when rockets flameout. Burn Nerv until complete ciurcularization. 

 

Landing Instruction:

Never attempt atmosphere reentry when empty. At Eve, mine Gilly for more rocket fuel. Back Kerbin, transfer weight to front tanker payload. 

In addition of retro burn, cargo bay door could be used help slow down reentry. Beware drag vector will affect stability. 

Atop Eve mountain, park and mine at flatter terrain above 7,500m. Use gravity potential and pendulum braking for optimal take off position around 7,482m height.

 

 

 

F02 Modified "Evean Extraction"

(Adaptive Rocket / Nuclear / Ion SSTO)

 

It is feared in the KSO, in case the rumored burrowing Evean purplemen attack Eve branch, and wipe out communication; agents at Eve branch might be left all on their own.  

Spoiler

 

Thus a single experimental evacuation craft devised from existing Infiltrator-type. The purpose is to explore possibility for a vessel, to take off from Eve mountain outpost, head to Kerbin on its own, without orbital aid nor any sort of refueling.

While retain same size and weight class like Infiltrator, ISRU had to be ditched for Ion thrusters. Even with 4200s ISP the goal is still difficult to achieve, in the end Kerbal engineers could only make 1525 dv out of Eve orbit. Although 220 dv from Nerv is quite capable for ejection, a single Z-1K battery and Ion thruster is far from practical as main workhorse. 

The navigation A.I., acronym HUMAN, simply refuse the boredomness of 700 Oberth manuvers to just raise orbit. 

The plane installed additional pair of main landing gear, gained powerful short take off capability(for one 532 tonner) over the Infiltrator's glide-off approach. 

 

User Instructions:

Spoiler

 

Refer to Infiltrator user instruction, with 3 additional notes:

1. Plane best at short take off, pitch up 20-25 degree and it lifts like a helicopter, when airborne quick retract landing gears to reduce drag. 

2. If nosecone temperature dangerously rise up during 30-40km Souposphere, either holding throttle or make slight manuver could help. DON'T forget dial throttle back.

3. The plane is capable of reentry/landing when empty, albeit rear first. More aggressive reentry is permitted, but don't expect any precision out of it. 

 

 

 

F02 Modified "Evean Extractor 2"

(Adaptive Rocket / Nuclear / Ion SSTO)

A stock Single Stage Eve to Kerbin shuttle

You could tell by first glance, this plane is designed to fly either foward or backwards. 

 

Spoiler

 

Eve's unforgiving gravity really took tolls here. Just by adding two Z-1k battery bank and two Ion thruster, the entire weight of craft skyrocketed 100 tons to keep up similar performance. 

The plane thus cannot achieve stable Eve orbit in one go. When PE raised above 80km, just kill engine and brace for brief reentry. 

The plane has a whopping healthy 1,600+ dv after single stage to Eve orbit. At same time still capable of a single 170m/s dv ejection burn, under 3 minutes.

With only 200 Ion burns to raise orbit to the edge of SOI. It's been simulated, it could take stranded KSO agent back home well within 10 years time frame. With nothing needed outside of Eve mountain outpost. 

The plane structure is soo overbuilt it could survive 3,500m/s Kerbin reentry like nothing.

 

User Instructions:
 

Spoiler

 

Take off instruction:

Point to the most flat potion atop Eve tallest mountain, full throttle and heads up 20-25 degree, when airborne immediately retract landing gears. Keep the plane from stall, it stables after airspeed reach ~300m/s.

 

Ascend profile: 

Aim for 30 degree climb. Activate Nervs and Ions at 15,000m alt. 

From 30km, keep TWR under 2.2. At 35km aggresively pull down for gravity turn. Exit souposhpere dial up full throttle.

Cautious the moment rockets flameout, it's not the most stable aircraft in the world.

Don't let Ions drain out battery, leave some juice for SAS. Raise PE ~83km before brief reenter, kill engine, close cargo bay to coast. Then obtain stable orbit at next AP. 

 

Orbiting advice:

Taking off from Eve tallest mountain will give 25~26 inclination. Don't attempt to fix this. Just put AP/AN almost dead on Kerbin orbit with ejection burn, and wait.

Even with the inclination, a good window (<150m/s to collision course) will usually come up within 10~20 years. 

Time mod is highly recommended. If no Time Warp mod present, raise PE above 120km to speed up stock warp, when carefully executed a tiny waste of dv is OK. Raise PE with Ions also save more liquid fuel for faster interplanetary correction.

Dv budget from Eve orbit: 1300 to edge of SOI, 130 ejection, 150-170 plot to Kerbin aerocapture, 20~50 reserve for room of error. 

For fastest safe Kerbin aerocapture set 40km Kerbin PE. For more precision feel free to experiment everything else. KSP celestial bodies are pretty stable,  If you did it correctly during interplanetary the craft likely shall arrive as is. 

 

Reentry Instruction:

Totally emptied the plane could withstand violent barrel reentry. Open all cargo bays for more drag. 

The plane equipped with a rear facing junior port to fix control direction. 

To fly backwards all control surface authority need to be manually retuned from action menu(increase the nose side authourity, reduce and invert engine side authority). Same goes for landing gear friction control(control from override to auto, reduce brake force).

When glide landing don't let airspeed fall too low, you need that speed at last moment to negate sink rate. Open cargo bay door will enhance stability but imediately drain airspeed, use with caution.

Use only 6 main landing gears for touchdown. Nose gear should be retracted otherwise could leads to mains overload. Only extend nose gear after plane touched down.

When brake is applied, keep pitching up to prevent rolling over. 

 

 

Screenshots:

Behold the majesty(or uglieness?) of zipped tri-cycle engine

 

Burning for moment of truth

 

Stable orbit achieved in first try, no F12, no save load, no mechanic-changing mod. 

KER having problem with Ions, and insists there're 1,823m/s delta vs after SSTEO. A hand calculation showed 1,626m/s

 

Simulated Ion return from Eve( Raise orbit is simulated via F12, total delta-v spent 1582. ~24 to 56 for reserve)

Final interplanetary correction 152m/s took 10 hours to complete( simulated by F12 burn 5 hour prior and after. Satisfied with no visual impact on trajectory and almost identical dv spent. Guess from a interplanetary orbit 10 hours is just like 10 seconds). Yes, that/s with 41m/s help from Nerv. Ions acceleration is acceptable(6m/s dv per 2 minutes), but charged from a single 1x6. 

 

Tumbly-wobbly

 

Your typical rear-first touchdown

 

Landing only with main gears, with nose gear retracted to prevent stress load up.

 

KSO agent single stage returned from Eve. T+10yrs 32d

 

Karma is, there's still lot of dead weight. Just remove front cargo bay and command pod could save 1.146t weight. It has potential to re-adapt ISRU, that leads to a SSTO Kerbin-Eve round trip, no orbiter / lander / tanker is ever needed.

 

 

 

 

 

Edited June 13, 2018 by recursive_mouse

[recursive_mouse]

Currently occupied rebuilding my car engine, when finished I'll start a true full-length Single Stage Eve to Kerbin mission with last craft.

[recursive_mouse]

Now it's officially stock Eve SSTO

Max takeoff weight 618t, fitted back with junior mining set, agile and pleasant to fly. Could hit Eve orbit with 1,687m/s dV reserve( more than 200 from Nerv ). 

craft.7z

revised (KerbalX)

Spoiler

 

 

Edited June 17, 2018 by recursive_mouse