How a startup is reinventing cryogenic rocket hardware

Astrophel Aerospace, a startup focused on reusable cryogenic rocket engines, is innovating turbopump technology to overcome one of rocketry’s toughest challenges: surviving extreme thermal gradients and mechanical stresses. Turbopumps must operate with one end exposed to turbine gases near 980°C and the other to cryogenic fuels below –180°C, spinning at 25,000 RPM. This creates severe material and design challenges, as thermal expansion mismatches can warp shafts, degrade seals, and seize bearings, often destroying engines and preventing reuse. Astrophel’s gas-generator-cycle turbopump, currently undergoing tests at ISRO facilities, aims to withstand 60–70 thermal cycles while eliminating battery packs, reducing mass, and delivering liquid oxygen at 4.1 kg/s with a pressure ratio of about 10. Unlike electric pump-fed engines that rely on heavy battery packs, Astrophel’s design uses a gas generator to burn a small fraction of propellant, driving the turbine and powering the