Mission Planning

[rcp27]

In a lot of discussion threads, the topics of time based mechanics come up, with things like time based funds and life support being the main ideas. The fundamental problem I have with this is not really knowing in advance how long a mission will take. In addition, when I start thinking about the next big mission to wherever, I have the problem of not really knowing when I hit the VAB how much delta V I might actually need to undertake the mission I have in mind.

For mission planning a the moment, what we have is the manoeuvre node system. They are great for figuring out the next step on an under-way mission, but they are a bit lacking when it comes to long term planning. The "skip to next orbit" button is fine for something like getting the right transfer from LKO to Mün or Minmus, but it's really too clunky for something like figuring out the right time to execute my Kerbin to Duna or wherever burn, because that burn might be hundreds of LKO orbits from now. Here's my idea for how to make things better. It would require only three basic changes to the way the game works now, but I think it would bring a huge benefit.

1. In the tracking station, in addition to letting me look at how the situation is with my various flights now, let me see how they will look in the future by having the option to project time forward (with any planned manoeuvres executed according to plan)
   
2. Let me add manoeuvre nodes to flights in progress in the tracking station view (including in "future time")
   
3. Give me a list of all planned manoeuvres for a flight, with times and delta V.
   

How does this help? Let's consider planning a mission to Duna. Let's say my plan is to have a main ship that will break orbit from LKO, transfer to Duna, circularise there, have a separate lander that will go down to the surface, do some Science, perhaps with a side trip to Ike because I like Ike, and then come home again.

To start with, I go to the tracking station and pick something I have sitting in LKO. We all probably have something there, be it a space station, a satellite to farm the "science from LKO" contracts, or just a dummy satellite we put up for the purpose of mission planning. I advance the view until I think there is a good looking transfer window, then add a manoeuvre to break Kerbin orbit and head for Duna. I then advance to arival and add a capture manoeuvre to get into Duna orbit. For some missions I might want a plane change or other correction manoeuvre part way. I then run forward for enough time to allow for how long I think my Duna and Ike landing missions will take, then look for what I think will be a good transfer window home, add a departure burn, the run forward to arrival and have a capture burn for Kerbin.

What i have now is a list of manoeuvres that I would need to execute to complete this mission. I know how long it will take, because the manoeuvre nodes will have times as well as delta V and direction data. I have a total delta V budget that I think is likely to be required for the mission, that I can use to plan the actual craft to undertake the mission. With this information, I can hit the VAB, build my ship, perhaps out of several components assembled in LKO. Once the ship is complete, I can go back to the tracking station, and repeat the mission plan for the actual ship. Once I have done all that, when I go to fly the ship, I will already have the framework of manoeuvre nodes I need pre-loaded into the flight. Of course it is still up to me to actually execute the manoeuvres, and it is likely that any aerobraking will have to be figured out by my own estimation. What it does mean, though, is before I start building my ship, I know that this particular mission will require however many km/s of delta V, and that the mission, if all goes well, will take 2 years, or whatever. I could also then figure out whether I have time to send Jeb on a quick run to Minmus and back before he needs to be on board the Duna mission.

If we had such a system in place, it would make flying to more exotic locations feel a bit more like "I have a plan" and less like "there's a good chance Jeb will be stuck on Duna until I can get a rescue mission together". Also, if I had a way of estimating how long the mission would actually take, planning things like life support would no longer feel like a random gamble, but feel more like something I can actually get to grips with.

[Nansuchao]

Transfer windows planner and Kerbal Alarm Clock are your solutions. Transfer Windows planner make you know what's the best moment to launch for a target, and all the info you need about (Delta/V, time of transition...) and make you add an alarm in KAC, so you can project your launch in time, an prepare what you need.