New rocket by Warsaw University of Technology students

During the official premiere on May 28, 2025, in the Grand Hall of WUT’s Main Building, Twardowsky 2 made a striking impression – measuring over 4 meters in length with a 200 mm diameter. It is a sounding (suborbital) rocket, designed for high-altitude measurements and frequently used for educational purposes.

The students’ new rocket consists of five main modules:

• Recovery: features a two-stage recovery system with stabilizing and main parachutes, operable via either pyrotechnics or compressed gas cartridges.
• Payload: houses a 1U CubeSat (10×10×10 cm cube) and an ejection mechanism.
• Avionics: includes an onboard computer and telemetry systems.
• Propulsion: a hybrid engine (fuel: ABS plastic; oxidizer: nitrous oxide), an active pressurization system, and on-launchpad fuelling modules.
• Tail: combustion chamber fairing and stabilizing fins for aerodynamic stability.

"During flight, the hybrid engine fires for about 8 seconds, accelerating the rocket to 490 m/s and enabling it to reach an apogee of 9 km," explains Eliza Łapińska, the project coordinator. "At this point, the stabilizing parachute deploys, followed by payload ejection, and closer to the ground, the main parachute is released. This ensures both the rocket and its payload can be safely recovered after the mission."

A Showcase of Cutting-Edge Engineering

Twardowsky 2 incorporates numerous innovative solutions:

• A hybrid propulsion system (self-designed, 5.8 kN thrust – the second most powerful in the Association’s history, capable of lifting over half a ton).
• Early engine shutdown capability, active pressurization system, and a spring-based payload retention and ejection mechanism.
• Modular design for easy replacement, configuration, and testing of components.
• Advanced avionics with full redundancy (enhanced reliability, aviation standards compliance).
• Integrated ground systems supporting remote fuelling, control, and ignition, with a strong emphasis on safety.
• Modern manufacturing techniques, including Selective Laser Melting (SLM)—3D printing in metals like aluminium and titanium.

"The rocket’s fuel grain (a cylinder with a specially shaped channel) is produced in-house using 3D printing, eliminating the need for external milling or casting," adds Piotr Łyżwa, the propulsion team’s lead engineer.

Final Tests and Upcoming Competitions

Development of Twardowsky 2 began in January 2023. Currently, students are completing the manufacturing of final components and conducting tests and integration.

"The remaining tests – including a second static engine test, telemetry verification, and full-configuration recovery system trials – are planned for this summer," says Szymon Krupa, a team member.

Longer-term plans include competing in international student rocket challenges, such as:

• European Rocketry Challenge (EuRoC) in Portugal (already qualified for the 2025 edition).
• Spaceport America Cup in the U.S.

These competitions pose a major challenge, as their requirements often change annually and are announced just – forcing teams to adapt quickly.

Adaptability as a Strength

Twardowsky 2 was developed by the Rocket Section of WUT’s Students’ Space Association. Currently, 30 team members are actively involved, with around 40 contributors since the project’s inception.

"We have a tight-knit, diverse team," says Łapińska. "In such complex, long-term projects, turnover is inevitable. But many new members quickly gain expertise and even become subsystem leaders."

The rocket was partially funded under the "Hybrid Rocket Engine for the Twardowsky 2 Sounding Rocket" project, supported by the Ministry of Science and Higher Education’s "Student Research Clubs Create Innovations" programme.