First Rocket Tutorial

Welcome to RP-1! Now that you've set up your install, it's time to launch a rocket. To make this a little simpler, we recommend that you start with one of the included craft files. You can pick the Aerobee or Meteo, either one will work quite well. Load one up in the VAB, and then simulate it using KCT. Separate the SRB as soon as it burns out, and then let it coast to apogee (apoapsis around Earth). In this default state, you can expect an apogee around SOME NUMBER for the Aerobee or OTHER NUMBER for the Meteo. Because, like in real life, rockets can have some variance and will leave behind some extra propellant, you won't get quite the same number every time, but you will be close. With some hyper-optimization you can get BIGGER NUMBER with the Aerobee and OTHER BIG NUMBER with the Meteo, but for a beginner, a better target would be REASONABLE NUMBER with the Aerobee and OTHER REASONABLE NUMBER with the Meteo. How do you optimize a sounding rocket? Well, here's how:

Drag

You want as little drag as possible, obviously. With FAR, this means very long nose cones. Run simulations with various sizes to figure out what works best. You may also want to make the fins smaller. Press "J" while mousing over them to edit them. Turn on the center of mass (CoM) and center of lift (CoL) overlays, and see how small you can make them while still keeping your CoL below your CoM. Because the SRB burns so fast, this isn't really a concern for that stage, so remove it while doing your calculations for this.

Dry Mass

Later on, upgrading tanks, avionics, and similar can help you make your craft lighter. At the start though, you'll want to focus on your fins and structural components like nose cones and decouplers. For fins, in the right-click PAW menu, you can adjust the mass-strength ratio. Too low and your fins will break off on ascent. Too high and you're carrying more mass than you need. The default of 0.25 is probably more than you need for a sounding rocket. Use simulations to figure out how much you can reduce it by. As for nose cones, while they are fairly light, you should replace them with cone-shaped fuel tanks to get the absolute max out of your rocket. If you're using a pressure-fed engine, make sure to set them to high-pressure. The option to add fuel in won't appear if the engine is pressure-fed and the tank isn't high-pressure. Finally, decouplers. The default cylinder is the heaviest option. A hollow interstage from the Procedural Parts mod will be lighter, and changing the shape of the basic decoupler to hollow with a very thin wall is the lightest. Make sure to enable crossfeed on your decouplers if necessary.

Burn Time

By clicking middle mouse button while hovering over an engine, you can pull up its TestFlight information. Its rated burn time is how long it is designed to run for, but running it for 5 seconds longer than that won't significantly increase its failure rate (beyond 5 seconds over will do so substantially). The stock delta-v readout is disabled because it's not accurate when using Realism Overhaul, so you should open up the MechJeb delta-v readout to do your planning. It'll show you how long each stage will burn for. Engines are quite expensive, so you should get the most out of them.

Getting Science

Kerbalism experiments aren't set to run when you first install them. You can right-click them and then start them in the PAW to get them to run. This can be done in the VAB or at the launch pad/in flight, but it's probably best to start them in the VAB so you don't forget later and don't have to re-enable them every time you launch it.

Building the Rocket

Once you're satisfied with the performance of your rocket, it's time to build it. Open up the RP-1 menu in the VAB, press "tool all", and pay the tooling cost. Tooling represents a wide variety and combination of machines, jigs, and molds set up to mass-produce that part. This speeds up construction significantly and will reduce the cost of each part. Because the initial investment can be expensive, it's best to try and reuse some of these tank sizes later on with other rockets. Once you've tooled your parts, click launch, purchase the parts when prompted (this'll only be a few funds; the unlock cost is only there for some organizational options you may want to take advantage of later), and then it should be added to your build queue.

Now, leave the VAB and go back to the space center view and open up the KCT window (A gear with clock hands in it). You can now see the progress of your rocket. If it's taking forever and the "upgrades" button is green, you forgot to spend your initial upgrade point. Open up the upgrades menu and put it into the VAB. Warp ahead until your rocket has finished construction, then roll it out and then click Launch using the KCT window. Once you're on the pad, launch it just like you did in simulation.

Congratulations! If all went well, you just launched your very first rocket in Realism Overhaul. If the launch didn't go well, build another one and try again.

Now, it's time for NEXT LOGICAL ARTICLE.