Interplanetary trips?

[Bubba Fett]

I've harvested science from the Mun and Minmus and it's looking like time to go interplanetary to find more. While I've managed to get probes to both Duna and Eve in sandbox mode, it was always clumsy and wastful and I've never learned to do it properly.

I've installed a mod called Transfer Window Planner that seems like it's providing the information for the trip.It's giving me a departure date and a phase angle. I assume the phase angle is the position of duna in relation to kerbin and the sun. It's also giving me an ejection angle. I understand that to be the direction I want to head relative to kerbin's prograde.
What I'm not clear on is how to get to that from LKO. Is there a mod for more accurate maneuver nodes that displays your ejection angle?

Among others, I use Kerbal Engineer. Is there a feature in there that would display ejection angles for a burn?

I'm running 1.12 so any mods suggested would have to be compatalbe with that version.

[CalmLlama]

Have you tried MechJeb?

[DragonDuncan]

I would also get Kerbal Alarm Clock to help warn you of launch window times for planned maneuvers along with MechJeb.

[Bubba Fett]

I guess I'll have to take another look at MechJeb. I switched from MJ to KER a while ago because I used to get a bit of microstutter and there were a couple more ground info functions that I liked better in KER. Hopefully that's been sorted.

MJ have any issues with the current version of KSP?

[Rhedd]

Yep. Mechjeb, Kerbal Alarm Clock, and the Transfer Window Planner are the main tools you need if you want to fly missions properly, instead of just guessing.

You don't have to let Mechjeb do the piloting, by the way. I usually just use the Maneuver Planner and Node Editor to set up my flightplans and fly them by other means.

I haven't run into any annoying issues with Mechjeb doing it that way, but then I don't think I have the most recent MJ version, either.

[Bomoo]

Ugh don't tell new players to install mechjeb, which is outright cheating. ♥♥♥♥♥♥♥ link them to tutorials on interplanetary transfers so they can actually learn how to play the game properly. "Hurr how to get into orbit? Open the debug menu and give yourself infinite fuel."

Here you go, OP, and ♥♥♥♥ the cheaters.

http://forum.kerbalspaceprogram.com/index.php?/topic/25169-tutorial-step-by-step-interplanetary-hohmann-transfer-guide-and-tips/

[Rhedd]

Bomoo eredeti hozzászólása:

Ugh don't tell new players to install mechjeb, which is outright cheating. ♥♥♥♥♥♥♥ link them to tutorials on interplanetary transfers so they can actually learn how to play the game properly. "Hurr how to get into orbit? Open the debug menu and give yourself infinite fuel."

Here you go, OP, and ♥♥♥♥ the cheaters.

http://forum.kerbalspaceprogram.com/index.php?/topic/25169-tutorial-step-by-step-interplanetary-hohmann-transfer-guide-and-tips/

How incredibly rude!

There are (at least) two ways to play KSP. The first is a fun, silly, by-the-seat-of-your-pants keyboard and a prayer method which is how the vanilla game is designed. It's a blast for a while, but many people outgrow it.

The second way is as a much more serious simulator, using techniques and knowledge similar to actual space missions, and learning some really cool facts along the way. Every real rocket ever flown had a computerized flight control computer, did you know that?

It's clear that the OP has been successful with the first method (so not a "new player"), and would now like to try his hand at doing it the more serious second way. It's also a simple fact that vanilla KSP doesn't give you the tools to calculate proper, efficient flight profiles, so mods are going to be needed.

Only an idiot thinks there's such a thing as "outright cheating" in any single-player game.

Personally, I think it's lame to feel you've accomplished something by going to Duna in a vanilla game with a stupidly over-engineered rocket that is about as similar to real rocket science as DOOM is to being a real soldier, but I'd never tell you that you were playing the game wrong, or suggest that you do it another way. Know why? Because I'm not an ♥♥♥♥♥♥♥.

So, do the world a favor and play the game the way you want, keep your insults to yourself, and let me, the OP if he wishes, and ♥♥♥♥♥♥♥ NASA fly missions with proper planning, actual math, and realistic tools.

Thank you.

PS: Oh, look, that link you posted instructs you to use MechJeb. "Hurr..."

[Bubba Fett]

So I've got a weird issue while trying to send a couple of probes ahead to duna to map it.

I plot a trip with the transfer window planner and it gives me the details for the burn including the time to make it, how much prograde dV, and how much normal dV.
The weird thig is that it's always wrong by about a half orbit. If I burn when TWP says, the ejection angle is completely wrong and drops me to Eve's orbit. If I move the burn about 15 minutes later using precise node then I get an encounter with Duna.

http://steamcommunity.com/sharedfiles/filedetails/?id=706238089

Is this a common issue or am I making some basic mistake?

[Weyland-Yutani HR]

Here's what I used for a long time before I got bored of setting up my own maneuver nodes. Ironically it's usually more accurate than using Mechjeb anyways.

http://ksp.olex.biz/

Go there and it will actually explain everything you need to do for the transfer. Don't miss this note, though...

"Warning: orbital inclinations differ between your origin and destination. Adjust the inclination mid-transfer as needed by performing a burn in the Normal or Antinormal direction to place your target intercept onto the destination body's orbit."

Happy sailing!

[Azunai]

the numbers look wrong. phase angle for transfer to duna should be something like 45° and the ejection angle should definitely be on the night side (ie something >90°). probably something like 150°.

the numbers in the display might actually work for a transfer from duna to kerbin (ie the return trip), though the phase angle would be ~ -70° for the return trip.

don't know what all the other info/controls are for. those two numbers are basically the only info you need to do a hohmann transfer. if the tool fails, i guess you're better off using the website Amallore linked. i've used that calculator a few times and it seems to work pretty well.

[Magnaheim]

I Agree, we should each play Our own way. Without MJ tho... Look up video of Marcus House. Career guide, Duna. There should be 1-2 video parts. Great tutorial, tho it is for a probe/lander combo, not manned. Tho it could be modified.

[Bubba Fett]

Hi guys,

Thanks for all the advice with this. While I've played for quite a while, I mostly do stations and surface bases at the Mun and Minmus.
By the time I get the science harvested it's usually time for a patch and I have to restart my career so I haven't had any reason to learn this stuff till now.

I had a look at the links and while informitive, it still seems like you need something external to the stock game to do this properly. I use mods, but I suppose a web site to provide the info would also work. Adjusting a stock maneuver node while you're focused on a spot a half solar system away wouldn't be much fun though. I notice that these trips are pretty finicky about precise values.

Anyways, I've managed to get a pair of probes on the way to duna to begin mapping and I've got about 100 days of game time to get a crewed mission launched in this launch window.

Transfer window planner seems to be working except that it always gets the burn time wrong by about a half orbit. With Precise node it's easy enough to shift the burn time by about 15 minutes and tweak it till I get an encounter.
I'll have to play with it a bit more plotting trips to other planets and see if that seems to be consistant with every trip.