SpaceForest has completed the first long-duration hot fire test of its upgraded SF-1000 hybrid rocket engine, which will power its PERUN suborbital rocket.

SpaceForest was founded in 2011 and is developing an 11.5-metre suborbital rocket capable of carrying up to 50 kilograms to an altitude of 150 kilometres. The company conducted two initial PERUN test flights in 2023, but both suffered anomalies that forced mission aborts before the rockets reached the 50-kilometre target.

Toward the end of 2024, the company completed an initial test firing of an SF-1000 engine with its upgraded combustion chamber, which lasted 25 seconds. In a 26 February update, SpaceForest revealed that it had followed the initial test with a full-duration hot fire test lasting 39 seconds. This marks a key milestone, as 39 seconds is the required burn time to launch the PERUN rocket into space. The test was conducted at the Central Air Force Test Range in Ustka, Poland.

The next and final SF-1000 rocket engine hot fire test will validate the company’s Thrust Vector Control system. Once completed, SpaceForest will move forward with an initial test flight of PERUN, equipped with its upgraded propulsion system. According to the company, the flight is expected to take place “in a few months” and will carry the rocket’s first research payloads.