--- title: How to Choose the Right Propulsion System for a Small Satellite Mission – A Practical Guide siteUrl: https://logzly.com/orbitinnovations author: orbitinnovations (Orbit Innovations) date: 2026-06-22T21:07:15.984175 tags: [orbitinnovations, satellite, propulsion] url: https://logzly.com/orbitinnovations/how-to-choose-the-right-propulsion-system-for-a-small-satellite-mission-a-practical-guide --- You’re staring at a spreadsheet full of numbers, wondering if your tiny satellite will ever get off the ground. It’s a common feeling for anyone trying to turn a cool idea into a real mission. At Orbit Innovations we’ve helped a few students and startups pick the right engine, and I’m sharing the simple steps that saved us a lot of headaches. ## Why Propulsion Matters Right Now Small satellites (often called [CubeSats](/orbitinnovations/a-practical-guide-to-building-a-cubesat-for-university-research-projects)) are exploding in popularity. Universities, hobbyists, and even big companies are launching dozens every year. But without the right propulsion, a satellite can be stuck in a useless orbit or run out of fuel before it finishes its job. Picking the right system early can keep your budget in line and your timeline realistic. ## Step 1 – Know What You Need to Do ### Mission Goal Checklist Write down the exact tasks your satellite must perform: - **Orbit change** – Do you need to move from a low Earth orbit (LEO) to a higher one? - **Station keeping** – Must you stay in the same spot for months? - **De‑orbit** – Is a controlled re‑entry part of the plan? - **Maneuverability** – Will you need to point a sensor or antenna precisely? At Orbit Innovations we always start with a simple table. If you can answer “yes” to any of the above, you need a propulsion system that can deliver that amount of change in speed, called delta‑v. ## Step 2 – Look at the Size and Mass Limits Small satellites are tiny. A typical 3U CubeSat is about 10 × 10 × 30 cm and weighs under 5 kg. Your propulsion hardware must fit inside that box and stay within the mass budget. - **Chemical thrusters** (like monopropellant hydrazine) are powerful but often heavy. - **Electric thrusters** (such as ion or Hall‑effect) are light but need a lot of electricity. - **Cold‑gas thrusters** are simple and cheap, but they give only a little push. At Orbit Innovations we once tried to squeeze a tiny chemical thruster into a 1U CubeSat and ended up with a payload that wouldn’t fit the launch adapter. Lesson learned: always check the dimensions first. ## Step 3 – Match Power Availability Your satellite’s solar panels and batteries set a hard limit on how much power you can spend on propulsion. - **[Electric thrusters](/orbitinnovations/understanding-electric-propulsion-what-engineers-need-to-know-for-the-next-space-mission) can need anywhere from 5 W to 100 W. If your panels only give you 10 W, a high‑power Hall thruster is out of the question.** - **Chemical thrusters** need a small amount of power for valves and heaters, usually under 5 W, so they fit tighter power budgets. When I was designing a test mission for Orbit Innovations, we had a 20 W power budget and chose a low‑power ion thruster that could run continuously for weeks. It gave us enough delta‑v without draining the batteries. ## Step 4 – Check the Available Propellant Propellant is the “fuel” that makes the thruster work. Different systems need different liquids or gases. - **Hydrazine** (common for chemical thrusters) is toxic and needs special handling. You’ll need a licensed lab and extra safety paperwork. - **Cold‑gas** uses harmless gases like nitrogen, but you need a larger tank for the same delta‑v. - **Electric thrusters** often use xenon or krypton, which are expensive but stored at high pressure. Orbit Innovations has a small lab that can safely handle hydrazine, but we still prefer non‑toxic options for student projects. If you’re on a tight budget, a cold‑gas system might be the easiest to source. ## Step 5 – Think About Reliability and Testing A small satellite can’t afford a failure in orbit. Look at the flight heritage (how many times the system has flown before) and the testing data. - **Commercial off‑the‑shelf (COTS)** thrusters often come with test reports and a warranty. - **DIY or experimental** thrusters can be fun, but they need more ground testing. At Orbit Innovations we once built a homemade cold‑gas thruster for a hackathon. It worked on the bench, but we discovered a leak only after launch – not a good story to tell. Since then we stick to proven COTS parts unless we have a solid test plan. ## Step 6 – Estimate the Delta‑V You Need Delta‑v is the total change in speed required for the mission. A quick rule of thumb: - **Orbit raise (LEO to 600 km)**: ~150 m/s - **Station keeping for 6 months**: ~10 m/s - **De‑orbit from LEO**: ~100 m/s Use the rocket equation (a simple formula) to see how much propellant each system would need. The equation is: ``` Δv = Isp * g0 * ln(m0 / mf) ``` - **Δv** = change in speed you need - **Isp** = specific impulse (how efficiently the thruster uses propellant, measured in seconds) - **g0** = 9.81 m/s² (standard gravity) - **m0** = mass before burn - **mf** = mass after burn Higher Isp means you need less propellant. Electric thrusters have Isp in the thousands of seconds, while chemical thrusters are a few hundred. Plug the numbers in a spreadsheet and you’ll see which option fits your mass budget. ## Step 7 – Factor in Cost and Schedule Finally, look at the price tag and how long it will take to get the hardware. - **Cold‑gas kits** can be under $5,000 and arrive in a few weeks. - **Electric thrusters** often cost $20,000–$50,000 and have longer lead times. - **Chemical thrusters** sit in the middle, but the safety paperwork can add months. At Orbit Innovations we once delayed a launch because the chemical thruster supplier missed a certification deadline. The lesson: always add a buffer for paperwork. ## Quick Decision Tree 1. **Do you need a lot of thrust?** → Chemical or high‑power electric. 2. **Is power limited?** → Cold‑gas or low‑power electric. 3. **Is safety a concern?** → Avoid toxic propellants, choose cold‑gas. 4. **Do you have money?** → Cold‑gas is cheapest, electric is most expensive. 5. **Do you need proven flight heritage?** → Choose COTS thruster with flight record. ## My Personal Takeaway When I first started at Orbit Innovations, I thought “bigger is better.” I tried to cram a high‑performance Hall thruster into a 6U CubeSat because it sounded cool. The power budget didn’t allow it, and the mission ended up with a dead battery. Now I always start with the mission goals, then match the propulsion to the power and mass limits. Simpler often wins. If you follow the steps above, you’ll end up with a propulsion system that fits your satellite like a glove, not a straitjacket. And that means more time for the fun part – collecting data, sending pictures, and maybe even inspiring the next generation of space explorers. Happy building, and may your orbits be smooth!