Dubai-based engineering company LEAP 71 has completed hot-fire tests of two 20 kN methane–liquid oxygen rocket engines developed in less than three weeks, moving from initial specifications to ignition. The engines were generated entirely by the company’s Large Computational Engineering Model, Noyron, without direct human design input.
Both engines, a conventional bell-nozzle design and a full-scale aerospike, produce approximately 2 tons of thrust (4,500 lbf) and are intended for orbital launch vehicle applications. The test campaign serves as another validation step for Noyron, a system designed to translate performance requirements directly into manufacturable hardware by embedding physics-based reasoning, engineering rules, and production constraints into a single computational framework.
From Specification to Hot-Fire Using a Single Engineering Model
According to LEAP 71, Noyron is designed to operate as an autonomous engineering system, capable of generating complex machinery end-to-end. The recent hot-fire tests provided real-world data that complements simulation outputs and feeds back into the model.
“Noyron is our ongoing attempt to comprehensively encode the process of engineering into a computational model that can operate independently of humans — radically compressing iteration times and making objects possible that were previously unfeasible. These physical tests — literally hot-firing the engines — generate crucial data that can only be obtained in the real world,” said Lin Kayser, Co-Founder of LEAP 71.
Space propulsion remains a central application area for the company. Over the past 18 months, LEAP 71 has conducted hot-fire tests of Noyron-generated engines at an average cadence of roughly one per month, with each design intentionally differing to probe the limits of the model’s physics representation.
Methane Modeling and Engine Performance Results
All engines in the campaign were additively manufactured using a high-temperature copper alloy (CuCrZr), with production carried out by German metal 3D printing specialist Aconity3D. The latest campaign marked a step up in both engine size and propellant complexity. Unlike earlier kerosene-based engines, cryogenic methane presents additional modeling challenges.
“Methane is a complex propellant to model,” said Josefine Lissner, CEO of LEAP 71 and Principal Architect of Noyron. “Contrary to the kerosene fuel we tested in the past, it undergoes significant density changes under different temperatures and pressures. So Noyron’s predictions need to be spot on in order to produce working hardware. Also, the increased size of the engines comes with its own operational challenges.”
During testing, the conventional bell-nozzle engine reached stable operation at nominal chamber pressure and thrust, achieving combustion efficiency above 93%, which LEAP 71 characterized as a strong outcome for an initial hot-fire.
The aerospike engine, which features a toroidal combustion chamber surrounding a central spike, was operated for a single burn due to startup transient issues. Nevertheless, it reached full chamber pressure of 50 bar, providing confirmation of the core design assumptions.
Next Development Steps
The test results are now being used to refine startup and shutdown behavior, particularly for aerospike configurations. An advanced ignition system, also evaluated during the campaign, is expected to be integrated in future tests.
“In the last 12 months we tested kerolox engines from 1.5 to 7.5 kN, using different materials and configurations. Noyron now delivers first-time-right rocket thrusters for kerosene and cryogenic liquid oxygen. We are confident that we are close to achieving the same for cryogenic methane. This test was an important step for us, validating that we can radically reduce the time for our customers to get to the launch pad with Noyron-generated engines,” said Lissner.
The 20 kN methalox engines represent about 10% of the thrust level LEAP 71 plans to test in 2026. The company reports that manufacturing validation is already underway for larger designs in the 200 kN class, as well as concepts reaching up to 2,000 kN, leveraging some of the world’s largest metal additive manufacturing systems.
AI and 3D Printing Boost Aerospace Innovation
The LEAP 71 test campaign reflects a broader shift within the aerospace sector toward AI-enabled automation and advanced additive manufacturing, as companies and governments increasingly adopt data-driven approaches to accelerate development while improving reliability and sustainability.
In Europe, GKN Aerospace has integrated Interspectral’s AM Explorer software at its Engine Systems Centre of Excellence in Trollhättan, Sweden, bringing real-time monitoring and AI-driven quality assurance into its metal 3D printing operations. The system captures live build data, detects anomalies through trained AI models, and produces consolidated defect reports, helping the company reduce material waste and accelerate the delivery of high-quality aero-engine components.
Similarly, the UK Government is backing a new £14.1 million initiative led by Honeywell to advance the production of certified aerospace parts using AM. Known as Project STRATA, the program aims to strengthen the UK’s aerospace supply chain and lower CO₂ emissions by developing next-generation AM processes. Honeywell’s Yeovil facility will lead the effort alongside partners including 3T Additive Manufacturing, BeyondMath, Qdot Technology, and the Oxford Thermofluids Institute.
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Featured image shows A conventional bell-nozzle design and a full-scale aerospike. Photo via LEAP 71.
