Welcome to episode 3 of our beginner’s guide to Kerbal Space Program (KSP). In the previous installment, we tackled the essentials of rocket construction. Now it’s time to launch that rocket and understand the fundamentals of how flight works in KSP. In this guide, we’ll explore everything from throttle and stability assistance to interpreting the vital navball. We’ll also touch on what it means to reach space—and why simply getting there doesn’t mean staying there.

A Quick Detour: Research and Development

Before heading to the launchpad, a quick look at the Research and Development center shows that some progress has been made on the tech tree using science points collected earlier. New parts have been unlocked, and a few of these are included in the current vessel design. However, this guide won’t focus on construction—we’re diving into flight.

Meet Valentina and the Rocket Setup

On the launchpad sits Valentina inside a Mark-1 cockpit, mounted on a relatively simple but functional rocket. This design features a liquid fuel engine—specifically the LV-T45 “Swivel”—instead of the solid fuel booster used in the previous tutorial. The liquid engine allows throttle control, which is crucial for fine-tuning your launch trajectory and managing G-forces.

Tuning the Thrust

Throttle control is new at this stage. Solid boosters don’t offer any control once ignited, but with a liquid fuel engine, you can manage your thrust in real-time. This guide assumes you’ve adjusted your engine’s thrust level to balance your thrust-to-weight ratio (TWR), preventing your rocket from launching too slowly or too aggressively.

Understanding the Instruments

Let’s break down the critical flight instrumentation that will appear on your HUD during launch:

The Navball

The navball is your most vital tool in spaceflight. Located at the bottom of the screen, this spherical interface tells you everything about your rocket’s orientation. It’s color-coded: blue for sky/upward, brown for ground/downward. The navball also features a compass bearing around its circumference, helping you determine direction (0° for North, 90° for East, etc.).

It shows your pitch, roll, and yaw—collectively known as attitude control. Mastering this will make maneuvering in space intuitive. Rolling the navball so the blue side is up can help synchronize your screen movement with the navball, making orientation easier to interpret.

Throttle and SAS

To the left of the navball is your throttle indicator. You’ll want to set it to full before launch. Also located nearby is the SAS toggle (Stability Assist System). Enabling SAS allows the spacecraft to maintain its orientation automatically, helping you fly in a straight line without constant manual corrections.

Altimeter and G-Force

At the top center of the screen is your altimeter, which shows altitude above sea level by default. Click the icon to switch to terrain-relative altitude.

To the right is your G-force meter—exceeding the red zone can damage your ship or knock out your Kerbals. Adjusting throttle can keep this within safe limits.

Atmospheric Pressure and Vertical Speed

Below the altimeter is the atmospheric gauge, showing how far you are from reaching space. KSP defines the boundary of space at 70,000 meters. Once you pass this, pressure drops to zero, and you’re officially in space—at least for now.

Next to that, the vertical speed indicator shows how fast you’re climbing or descending. A rapid increase in vertical speed indicates efficient thrust; a drop warns you that gravity is winning.

Prograde and Retrograde Icons

As your rocket flies, you’ll see several markers on the navball. Two of the most important are:

• Prograde (open yellow circle): Indicates the direction of your current velocity.
• Retrograde (yellow circle with an X): Indicates the opposite of your motion vector.

Clicking on their corresponding buttons in SAS will align your ship to either direction. Retrograde is typically used for slowing down or reentry.

Launching and Reaching Space

Once your throttle is maxed and SAS is active, hit the stage button to launch. You should see your rocket rising and passing key altitude markers. Monitor the throttle to manage G-forces, and keep an eye on vertical speed.

Once you’re out of fuel, your momentum will carry you upward. Switching to map view shows your current trajectory—represented by a blue arc. In this case, the arc reveals that the rocket will peak at around 165,000 meters before descending back to Kerbin.

A Word on Staying in Space

Getting to space is one achievement. Staying there is another. Unlike in movies where objects float endlessly once in orbit, KSP models realistic physics: you need horizontal velocity to stay in orbit. Your current rocket ascends and then falls back due to gravity—much like throwing a rock really high. Orbiting will be the topic of the next guide.

Descent and Parachute Deployment

As you descend, atmospheric drag increases. If your capsule has a heat shield or is shaped aerodynamically, it will naturally orient itself retrograde—pointing bottom-first to minimize heat stress. Once you drop to a safe altitude and speed, your parachute icon turns green. Hit the stage button again to deploy it.

Initially, the chute will semi-deploy, and once low enough, it will fully open to slow your craft to around 5.5 m/s—safe enough for splashdown.

Recap: Key Takeaways from This Episode

• Navball Mastery: Learn to interpret pitch, yaw, roll, and heading.
• Throttle Control: Manage G-forces and fuel efficiency.
• SAS Usage: Stabilize your flight without micromanaging.
• Flight Indicators: Altimeter, vertical speed, G-forces, and pressure are your guides.
• Prograde vs. Retrograde: Understanding directionality is key to maneuvering.
• Space Isn’t Orbit: Altitude alone doesn’t equal a stable orbit—you’ll need speed and trajectory, which we’ll explore next time.

Valentina has safely returned from her brief trip to the edge of space. Now that we’ve covered the core elements of basic spaceflight, the next guide will go deeper into achieving and maintaining orbit. Until then, safe flying, and keep experimenting!