RoboRay

Oooh, nice. Those will be awesome for Duna.

The Crew Manifest mod allows you to add or remove crew on the pad.

Return cost is nominally the same as the outbound cost. The differences you are seeing are likely due to eccentricity, as the planets have moved considerably. Aerobraking differences can also result in significant deviations.

If you're suggesting this is a terrible screenshot because it doesn't include a fully illuminated spacecraft, then I have to disagree.

If you want to confine yourself to a tiny part of a larger discussion, feel free. But don't pretend that there's not more being discussed, especially when making absolute statements that don't apply absolutely.

This is a fantastic way to teach yourself what you need to know for more advanced future missions. I more or less followed the sequence of mission goals the early US program achieved. You can get a great sense of accomplishment from each milestone along the way, rather than repeated failures and retries to master it all at once.

It's extraordinarily relevant. We are not discussing just "shoot them and go home" launch vehicles (where no, it isn't relevant for the reasons you mentioned), but also vehicles that will remain in space for extended periods of time. If you fuel them with hydrogen, the tank will be significantly depleted when they arrive at their destination and need to use the engine again.

You can not directly launch into an orbital inclination lower than your launch-site latitude. It's physically impossible. What you can do is launch to a minimum-inclination trajectory and make a plane change later, at a lower latitude, to attain a lower inclination. This can even be done as part of your launch, if you desire. If you desire an inclination equal to or greater than the launch-site latitude, you can launch directly into it without a post-liftoff plane change, which is why I made the distinction. Yes, this is in agreement with what I said. I didn't say there was a mathematical reason it was done, just that it's done to simplify the guidance solution to maneuvering around a single axis. And doing things conservatively because you know that method works reliably doesn't make it merely "out of habit." If it was purely out of habit, it would be a matter of whimsy, not conservativeness with incredibly expensive equipment (and sometimes lives at stake).

I was trying to describe the physical orientation of the craft, not listing reasons for doing the maneuver. As the real KSC isn't on the equator like the Kerbal version (nor is Vandenberg, Wallops, Baikonur, Jiuquan, etc...), the minimum orbital inclination is the launch-sites latitude. The inclination can be increased (if desired) by adjusting the heading north or south (depending on what the target plane is), which is part of what the roll maneuver is doing (orienting the craft so that only a pitch maneuver is needed to start the turn, rather than a combination of pitch and yaw). It's definitely not just done out of habit.

Meanwhile, at the South Kerbia Obervatory, Dr. Ned Kerman is reviewing the latest telescope imagery of the Mun and, startled, says loudly "When did the Mun get a ring?"

Oh, it's not a "request for immediate action" or anything. But if you do ever find yourself in the "I want to make a new envelope, but which kind?" situation...

The issue of hydrogen isn't efficiency (it's the best, if pure Isp is the only concern), but about the problems of storing it. The much lower density (yes, even in liquid form) requires vastly more volume (and mass) to hold it. Not to mention that, over time, it boils off and escapes right through the walls of your huge, heavy storage tanks. In fact, the reason that RP1 or something else is typically used for fueling the first stage is simply because it's so much denser. You give up Isp in exchange for having a much smaller, cheaper, easier to design and fly vehicle. LH2 is great for launch vehicles which you can fuel and send straight up, the upper stages in particular, but it's simply impractical for craft that will need to store it in space for long periods of time. I think Methane/LOX is about the best option for storable propellents, especially when you consider that methane can be manufactured pretty easily and cheaply on any world with CO2 in the atmosphere. And the Isp isn't that much worse than LH2.

It depends on the curvature of the turn. I start mine at 1km and make a very gradual turn, still at 80 degree climb angle when I clear 10km, so it's effectively vertical from a drag-reduction standpoint. However, most KSP players seem to prefer just flopping their craft right over to 45 degrees instantly (giving up efficiency to steering losses in the process). For them, waiting to 10km (+/-2km) is essential. It's not as good a way to do it, but it's easier.

The roll program is different. The shuttle was not positioned on the launchpad in a way that that they could simply pitch the nose slightly down toward the horizon to start their gravity turn. They had to roll the craft first, shortly after clearing the tower, to get the craft in the proper "wings aligned with the horizon and the vehicle inverted (crew head-down)" orientation for the turn.

I would love to see more deployable options, too. I can work with the parachute design, and I do like it, but variety is nice. Maybe something new could be a more traditional blimp-style envelope, bigger than the parachute design, for larger airships... As is, even a moderate-sized craft needs multiple envelopes for Duna.

There's not much we can do without some pictures of the ship. Most design problems can be identified in a good screenshot or two, but we're just speculating without them.

I kind of like it that way. It gives me an excuse to do a little more flying, with a shuttle-style roll maneuver.

Uhm, yeah... Sorry, but I'm going to stick with "There are better ways to do that."

An answer right in the middle of the reasonably optimal range for all but the most unusual designs (8 to 12km) is certainly not "absolutely wrong" Mr. "Real KSP Pro." But if you want to be absolutely wrong, keep calling it a gravity turn. What you and pretty much all KSP players do is in no way a gravity turn, it's simply a pitch maneuver (assuming you even bothered to orient the craft in a standard flight attitude where pitch controls your climb angle). A real gravity turn starts as soon as you leave the launch pad.

LOL, no, just joking.

To clarify... The most efficient burns happen on the opposite side of Kerbin to where your intended destination will be when you reach it.

Do not launch straight upwards to escape if efficiency is desirable... you're incurring gravity losses the entire time and you lose the rotational benefit of the planet. Do a gravity turn as normal and simply continue your prograde burn rather than circularizing if you want a direct launch to escape. You'll need to launch just before KSC reaches the proper ejection angle for the transfer orbit, however. Also do not escape into solar orbit then try to set up a Duna transfer, as that's much less efficient than making your transfer burn in low-Kerbin orbit (or as part of your launch-to-escape burn). Yes, this is the most efficient way to fly the mission, and it's also the most challenging to accomplish.

You never "need the vertical speed." If you produce enough horizontal speed, it will quickly become vertical speed as the curved surface drops away beneath you. And you need the horizontal speed... you're going to have to burn to produce it later if you don't go ahead and do it now. You may as well build speed and move your Ap upward with the same fuel, unless you've simply got a lot of extra fuel to get rid of. At 10km, you've left 90% of the atmospheric drag behind. Continuing upward at the expense of horizontal velocity is counterproductive. Go ahead and start a gradual turn, keeping your nose within a few degrees of your prograde marker for maximum efficiency.

Real-time mission to Jool. I'll let you know when I get there, sometime around January.

When you arrive at the destination, your orbital inclination is related to the latitude of your periapsis above the surface. So, if you put your Pe right on the equator, you'll have an equatorial orbit (and if you put it on the "outer" side away from the body it's orbiting, you'll be in a standard easterly orbit). If your Pe is over the north or south pole, you'll have a polar orbit. Note that your minimum inclination will increase if you're not approaching the destination world on its equatorial plane... you have to be perfectly parallel with the equator and directly above it to attain a zero degree inclination without a plane-change burn during the capture.