Which mission would you launch next?

[celem]

Hello fellow mission planners and flight controllers!

I'm in a bit of a bind, I cant decide what mission to fly next, so I thought I'd come pick your brains and see if anyone has some ideas I havent thought of.

To set the scene...

Im playing Real Solar System with all the realism mods. So RO/RP-0/DRE/TAC/RT/EngineIgnitor plus a fistfull of configs and all the other junk needed to turn KSPs world into ours.

My tech is probably still pre-Apollo. Best payload masses at this point are around 7.5 tonnes (off 400 ton launchers), no docking ports. I do have a deep-throttle landing engine (a tiny one). For those that know the hardware im dealing with no...I have neither F1 nor J2, cant afford the R&D funds.

I've done a manned flyby of the Moon at 3,000km to test my service module, this is my 7.5t max-tested payload and keeps a 'naut up for 65 days with 3k dV.

Ive got a couple of probes in Lunar orbit so RT coverage is ok, signal delay is 1.2 seconds.

Lunar Mission Options:

Manned Orbit - positive: can do with current systems. negative: teaches me little (good hardware test, poor sci-yield)

Unmanned Landing - positive: im confident my tech can land a probe now that i have a throttling engine, ive done lunar landings without a throttle before and its not easy. negative: i would have to deal with a 1.2-1.5 second signal delay for the duration of landing, it varies a little depending on the exact routing through my geosynch ring. I would probably have to add a relay or two also in lunar orbit to ensure the lander doesnt drop comms.

Manned landing - positive: woo science baby, skip a couple of logical steps and all that. negative: no docking ports, payload limits probably preclude Direct Ascent. (again, done this before and I needed the F1 and J2 to get it to work). I could conceivably pull off Lunar Orbit Rendezvous without ports, EVA transfer... not sure. Means multiple-launch due to weight of life support systems. No existing systems, current lifeboat would need modifying to be able to make a return from Lunar orbit.

Other stuff:

I can in theory get flyby probes of Mars/Venus with ease, perhaps even establish orbit. My dishes can reach this far. You can get a lot of dV into orbit with limited mass if done right and I have a reignitable topstage Hydrolox engine (high isp, but boils-off so useless after a few days). Ive sent probes into Solar orbit with apoapsis as far as just shy of Jupiter. With a stretch and maybe a grav assist I might make Jupiter/Saturn flybys but current comms tech cannot reach that far, so I would need to greenlight a bigger dish to mount on them (I also start to have issues with solar panels sucking at these distances, no RTGs)

So what mission would you fly next? Orbital sci at Moon is pretty much done, likewise low/high Earth. I have no stations.

edit: its career mode 0.90 Should be obvious its career, but thought i'd throw that out there. So money is a thing.

edit2: since its RSS and is generally harder than regular KSP (especially with all the mods) I should note im an average pilot. I can get into orbit on budget, can launch into inclination within a degree or two and can manage some semi-complex tasks like dogleg ascents. Im not so great at timing launch for direct rendezvous, which i struggle with even in stock, but with the need to match incline too....forget about it.

Edited March 20, 2015 by celem

[Streetwind]

From the options presented, probably the unmanned landing.

The signal delay can be made less of a problem by wasting a bit of fuel, if able to do so. Aim to arrest your descent completely about 50 meters above the surface, therefore if you miss it slightly due to the delay you won't slam into the ground. Then you can use your deeply throttleable landing engine to gently float down, making sure that your vertical velocity always stays around 6 m/s by working the throttle around the hover point. Your landing legs should be able to handle up to 12 m/s, so by going half that speed, you have a safety margin.

It's not efficient, but it's safe!

[Taki117]

I'd toss up a RemoteTech relay around the Mun first (Maybe a couple) to reduce your signal delay to something more manageable, then go for the unmanned landing. I'm not familiar with the scales you are dealing with (I use the 1/10th config for RSS) If at all possible I would take some contracts to put satellites in orbit of the Moon (Mun) and use those as commsats. The same goes for anything in Kerbin orbit.

[Streetwind]

Relays don't decrease signal delay - in fact, the extra hop will slightly increase it. Only local command stations let you get away without the delay all the way back to Kerbin. Which requires a RC-L01 Remote Guidance Unit and a crew of six Kerbals to be present. Not only is it likely that he doesn't have the required parts yet, but he'd also have to launch them and set them up in lunar orbit ahead of the probe landing... and then recover them afterwards.

That's a whole lot of effort to eliminate a small delay.

[eddiew]

A Mars landing is arguably easier than the Moon, since you can come in shallow and aerobrake At least, that's largely why the Vikings were so successful so early ^^

[celem]

Some excellent ideas and comments, thankyou!

@Streetwind. I'll take a look at how much buffer dV I can get onto a probe lander and perhaps try the early suicide burn you suggest. It is indeed a less-scary concept than it was without a throttle.

@Taki. To lower the signal delay I could in theory mount a large dish on the lander and take a link direct to the Earth or its nearspace, but cutting out the Lunar links doesnt save much path length. Rt already uses the shortest path it can find though, so a large dish means shorter delay whilst LoS to Earth is available. Your comment on contracts helped a lot though, had forgotten these and am low on funds, so it will significantly help finance any expansion in this area. Especially given I can fill the contract then move the sat to where I actually want it.

Indeed, I dont have parts for a local command station, nor yet the capability to keep that many astronauts alive for long enough.

@eddiew. A suggestion not on my list! Headed to wiki and looked up the Viking Program. I could probably swing that with the tech at hand, nice mission.

I think ultimately im going to go for the unmanned landing along with a strengthening of Lunar comms (maybe a trojan ahead and behind, its a slightly longer path again but good uptime and coverage)

The Mars probe landers a la Viking are too cool. Its on the slate for now after unmanned Lunar landing and before manned Lunar since it doesnt require further evolution of life support/energy generation. I could replicate their design with current hardware and have them separate into orbital relay and lander.

I'll mark this answered now since I got some good feedback, but feel free to continue to comment if you have an idea or viewpoint, I'll be around and my RSS games proceed at a sedate enough pace that I wont be doing all this in the immediate future.

edit: just put another local relay into a lightning polar orbit around the moon, its got 95% uptime to the geosynch ring and covers most of the northern hemisphere. Moving my existing relay to an opposite lightning orbit for the southern. Stabilises the Lunar grid greatly and costs at very little in extra delay even when the relays are at apoapsis.

edit2: So I started putting together my Lunar lander, making its propulsion section a relay because it seemed smart, then realised that I was pretty much building a Viking, so gave in, added a chute. You win eddiew... off to Mars. I even have a Centaur analogue, just need to whip my booster into line with the Titan-III

Edited March 20, 2015 by celem
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