rogerwilco

Thanks for your help guys, I think the first number I came up with was: sin(θ) = Opposite / Hypotenuse sin(30) = 600 / Hypotenuse 0.5 = 600 / Hypotenuse Hypotenuse = 600 / 0.5 Hypotenuse = 1200 So the orbit altitude is 600Km. Thanks Rhomphaia, when I did as you said and corrected that mistake it came out at 1199.9, so I assume my half radio distance (line of sight distance from satellite to satellite) is correct. With a line of sight distance (x2) resulting in 2078.46Km, this is under the Communitron 16 range so I can avoid adding a 32. I will go about setting this up and see if I can make this work. Thanks chaps! - - - Updated - - - Good idea about the docking port!

So I found the RemoteTech addon and I really think it is fantastic. It really makes you think a little harder about Why your are doing a particular mission rather than How. The first step in RemoteTech is to launch an array of satellites from which you can relay mission controls instructions, so you retain control of your craft. From their tutorial, they recommend placing 3 satellites in an orbit of around 1000Km. So whilst I could take this at face value and just do as they say, I wanted to understand why they had chosen this value, and I wanted to understand how to calculate what you would need for different configurations or numbers of satellites, so that I can create networks around other planets without resorting to someone's youtube channel for instance. What you want in a relay satellite configuration is for each neighbor satellite to be able to see each other, so if you have 3 satellites, each satellite must be able to see the other two. This also means that they can see every longitude on the body they are orbiting. I visualized this as a triangle bounding a circle, and wondered how to calculate what the altitude of the satellites must be in order for this to be accurate. Whilst I am no maths guru, I can at least do a little trig. I have come up with a value which is that if you can get a satellite orbiting at 51Km off Kerbin (ignoring the mountains and atmosphere) then that would actually do the job. My question is, am I incorrect in this? If so, why? And if not, why has the tutorial chosen such a large distance between satellites? Bearing in mind the further orbit you have the stronger (more power/mass/cost/sci level) requirement of the antennas. If I am correct that 51Km is just fine with 3 sats, can I just plop them all in a nice and tidy 80Km orbit and save myself the cost, power, dV to push them higher? Or am I totally wrong and need tearing a new one by the maths capable here. Just trying to learn to fish rather than asking what orbit I should be at! Many thanks you helpful KSPers! Here are my workings:

Wow, loads of input - thank you so much guys. You've give me lots of think about. I think I have over estimated the amount of dV required, but I wanted to make sure I didn't just fall short because of a lousy orbit entry or some such. Maybe I'm misinterpreting the chart, I'll read up about that. Everyone says move to Mainsail, I will do that, capri3101 thanks for your detail, I will have to spend some time thinking about what you've said until I get it. According to some comments, the main reason I'm using the liquid engine in the first stage is so I can gimbal the thrust for me to gravity turn, otherwise the solid boosters just sit there going straight up I understand that my TWR must be much higher than it is, but I also understand that there is no benefit with a stupidly high value here. Randazzo, they are two monopropellant tanks, not sure why they are not symmetrical it was not intentional... So I did actually make it to the moon and back (after hours) this evening. The change was I modified the transfer stage to use two T800 tanks, rather than T800 +T400 so I had enough juice in these to totally kill the horizontal momentum of the Mun, and most of the vertical. This meant I had 2000 dV on my way back, and like someone said above, I only used about 1,400 dV. Thanks guys, very rewarding when it actually works!!

Hi Kelderek, Thanks for your response, I do not have that engine but I think it is an upgrade. I shall go with that and bear in mind the TWR target of 1.5 for the middle atmosphere.

Okay, so after you guys were so helpful on my orbit question I want to ask something a little more academic. I've been reading about the deltaV requirements for different stages/transfers and I know what I want to acheive. I am using the numbers from the dV chart and adding 30% for my inept rocket handling. So I have the following route (working backwards for mass): Moon Lander - Landed: 830 (To moon orbit) + 1200 (To kerbin orbit) = 2030m/s required. I have created a lander with 2250 m/s and it weight 4.5 Tons (module, fuel, engine, paracute, science etc). So now I have a mass of 4.5 Tons to get to Moon orbit, so I need a Kerbin -> Moon transfer stage. This requires 1200 (to Moon orbit) and 210 (capture Moon orbit) gives a requirement of 1410 m/s. Using a T400 and T800 tank and a T45 engine (1,500 m/s) I have a transfer stage weighing 8.3 tons, so I have a total of 17 tons to lift into a stable Kerbin orbit, so that I can launch my transfer stage to the moon. Great! Just need a lifter.... This is where my numbers get unstuck and what I think should work, doesn't always. I know I need 4500 m/s to get to Kerbin orbit, now when I use this configuration which I believe should work, I sometimes use way more deltaV than 4500, and often my Peri decays before I can get actually get to the Apo on the other side to raise it! Whilst I almost always get to 70km, when firing prograde it doesnt always provide enough force to stablize the orbit... Any pointers here? I think I'm on the right track, just missing something critical. Thank you for your help.

Thank you so much everyone, I managed to do it like you said, Axelord your diagram was very useful. I now have some spare cash again! I thought this mission was going to bankrupt me!

Hi, Love the game, but am getting very irritated on how to achieve the orbit contracts, the first time was Kerbin, which I tried and couldnt get to work, now I've made it to Mun (eventually, after hours) and still have some fuel left. Unfortunately I've tried to match the orbits, but I cannot figure out how to change the timing of the orbit so that I match the contracts requirements. You can see in my screenshot the contract requirements, I believe I should be within the minimal on Apo an Peri, as well as inclination (I had been 29.2 almost exactly but tried other things). Please could someone help me with this? It's way past my bedtime! Thank you!