Arkonor

Thank you for all of your responses. They have been helpful in several ways. Tonight was the first time I have ever delivered something into a stable dunar orbit. Most of the time I was tweaking the orbit so it encountered the planet WITHOUT passing the Duna orbit. It was impossible and it consumed a lot of time. So, in the end I chose to escape from Kerbin SoI with a single push (the double münar boost consumed more delta V, and a single münar boost didn't give me a decent trajectory because it intersected Kerbin's orbit) In interplanetary space, the only maneuver I could do to lower my periapsis at Duna was to burn retrograde shortly before entering Duna's SoI, it went from 22m KM to 8 more or less (and 22 was my best attempt maneuvering over Kerbin, the worse, 40m or so) Meanwhile, I learned how to use the alarm clock to pause the game and kill the warp, it was a very productive time to test things, think, and pray for a non-destructive nor very far encounter with Duna. Once inside the planet's SoI, and seeing the weird polar fly-by over Duna, my kerbals in the control room calculated several ways to reduce more over the periapsis and to attempt a succesful aerocapture. After several minutes testing things in the simulator and moving the hands a lot in front of their faces to rehearse the complex maneuver, they came up with a solution. Instead of the classic "pedal-to-the-metal" retrograde burning they love so much, the radial burning proved to be a much more resourceful idea. Since Duna's air is so thin and low, as much as the remaining fuel in my probe's tanks, the maneuver took place at 10km over the north pole surface. Fortunately, physics are not so reallistic to make my ship burn like a match, though the visual effects were impressive. Those were my truly 7 minutes of terror (in fact it was much less, but high speed and terror are capable of bending the fabric of space-time), the ship started to brake a lot, the apoapsis was in free fall and also the periapsis, just a tad slower. Later I would recall that my probe was fitted with a parachute (for unknown reasons, the safety department usually attach these things whenever they had the chance to sneak into the hangar) The thin vapors of fuel, less than a liter, were incredibly efficent because they allowed me to raise my periapsis from 8000m up to 52km, and lowering the apoapsis up to 450km when the engine died. Tomorrow I'll post pictures if you want.

Firstly, yes, I have read the tutorials, but the problems I am encountering are not mentioned (unless they are somewhere in the dozens of pages of each thread) To avoid the need of long explanations I'm going to the point - The two biggest problems until now are: 1) Using the in-game maneuver planner you can only see the delta V of the first maneuver. So I'm going blind until I pass that node and erase it. I would want something better to plan how much delta V I'm going to spend in each node. 2) In the cases when the planner shows that I'm going to do a fly-by near Duna, the closest approach is around 40 million kilometers. Changing any parameter in the maneuver node loses my target and I have to start over again. Therefore, I can't correct it using aerobraking (too far from the atmosphere) nor using the gravity to brake (I barely manage to pass close to the planet) To get the most window to do the trip I'm using this calculator http://ksp.olex.biz/ . At least the planet phase is correct, the ejection angle is more difficult to adjust but I try to approach the best I can do it. - Also, I've tried other forms to save delta V, like planning a gravity boost on Mün by passing twice (first time to get a wide orbit around Kerbin, and the second to leave the Kerbin system, and eyeballing the ejection angle) However, it's not possible to know if I am saving fuel or not because I can't see the delta V in each node. This maneuver is very restrictive because it gives you a fixed apoapsis, so you can't place the next node anywhere you want to do a prograde burn to raise it. It must be near the point you are leaving the Kerbin system, so if if the planet is not in the intersection of its orbit and your apoapsis, everything is futile. * Sometimes I have to change these maneuvers because they modify greatly my orbital plane PS I'm always starting from a 600km circular orbit around Kerbin, so I can use the maximum speed in the time warp to wait until the planets are in the right position. That leaves me a delta V of 1550 m/s aprox for my probe. PS2 Next time I'll try to plan an insertion orbit against the direction of Duna to see if that helps to brake.