HAAS

Named in honor of the Austrian-Romanian medieval rocket pioneer Conrad Haas (1509–1579), the Haas rocket series was designed as a lightweight, responsive orbital launch vehicle

Overview: from Concept to EcoRocket

The Haas program began in 2012 as an initiative to build a highly cost-effective orbital launch vehicle. Across years of transatlantic operations, including stratospheric test campaigns, support infrastructure for ESA’s ExoMars, and UAV technology development in the US, the Haas technology continuously evolved.

Today, the advanced composite architecture, and propuslion system of the Haas rocket live on as the orbital upper stage of EcoRocket, paired with clean, low-cost Launch Assist System (LAS) steam propulsion lower stages.

Haas 2CA: Single-Stage-to-Orbit (SSTO) Architecture

The Haas 2CA was engineered as a Single-Stage-to-Orbit (SSTO) rocket designed to deliver 100 kg of payload to Low Earth Orbit (LEO) at an unprecedented target price of $1M per launch.

By utilizing a single stage fueled by Hydrogen Peroxide (H2O2) and Kerosene (RP-1), the Haas 2CA achieves an exceptional mass fraction enabled by four key technological pillars:

Dense Propellant Combination: Maximizes propellant mass while minimizing overall airframe volume.
Advanced Composite Pressure Vessels: Ultra-lightweight composite tanks capable of withstanding operating pressures without heavy metallic structures.
Executor Linear Aerospike Engine: Delivers optimal aerodynamic expansion efficiency across all atmospheric flight levels, reducing overall fuel consumption by up to 30% compared to traditional bell nozzles.
Differential Thrust Vector Control (TVC): Achieves pitch, yaw, and roll control by throttling individual combustion chambers, completely eliminating heavy, complex mechanical engine gimbals.

Propulsion: The Executor Linear Aerospike Engine

Aerospike propulsion technology—extensively researched by NASA since the 1960s for programs like the Space Shuttle and VentureStar—eliminates the efficiency limitations of traditional bell nozzles.

A conventional bell nozzle operates at peak efficiency at only one specific atmospheric altitude (typically near sea level). Beyond that point, fixed nozzle walls prevent the exhaust gases from expanding fully as ambient atmospheric pressure decreases.

In contrast, the Executor Linear Aerospike Engine allows virtually unlimited gas expansion ratios across the entire flight envelope:

Altitude Thrust Gain: Gains 33% more thrust at high altitude compared to sea level performance for the exact same propellant mass flow.
High Efficiency at Low Pressure: While state-of-the-art engines like the Merlin 1D achieve a vacuum specific impulse (Isp) of 311s at ~100 bar chamber pressure using LOX/RP-1, the Executor Aerospike achieves 314s vacuum Isp at just 16 bar chamber pressure using H2O2/RP-1.
Simplified Gimbal-Free TVC: Thrust Vector Control is accomplished by dynamically adjusting the mixture ratio across the 16 individual combustion chambers. Eliminating hydraulic gimbal actuators keeps production costs low without sacrificing precision or performance.

Advanced Composite Airframe & Mass Ratio

For an SSTO vehicle, every kilogram saved on dry structural mass directly translates into additional payload capacity.

The Haas 2CA airframe is built entirely from advanced composite materials, achieving a mass ratio of 29:

World-Class Structural Efficiency: Despite operating in a pressure-fed configuration, the composite tanks are among the lightest ever integrated onto a space launch vehicle—delivering twice the structural efficiency of the stage-and-a-half Atlas rocket.
Flight-Proven Durability: Composite propellant tanks for hydrogen peroxide and RP-1 have been extensively tested by ArcaSpace since 2002, maintaining a 100% structural reliability record across all flight operations.

Technical Specifications

Length: 16.0 m
Diameter: 1.3 m
Empty weight: 550 kg
Launch weight: 16,290 kg
Engine type: linear aerospike
Number of stages: 1
Engine feed: pressure fed
Pressurant: heated LHe
Propellant: HTP + RP-1
Cooling type: ablative + film
Engine run time: 272 s
Thrust at sea level: 22,920 kgf
Thrust in vacuum: 33,500 kgf
Specific impulse at sea level: 230 s
Specific impulse in vacuum: 314 s
Peroxide flow rate: 88 kg/s
RP-1 flow rate: 10 kg/s
Mixture ratio including film: 7.46:1
Tank pressure: 20 barg
Chamber pressure: 16 barg
Payload to LEO: 100 kg

Evolution: Haas + LAS = EcoRocket

Following the development of the clean, low-cost Launch Assist System (LAS), ArcaSpace integrated the core technological advances of the Haas program—including the composite aerospike propulsion, high mass ratio tanks, and avionics—directly into the EcoRocket platform.

In this integrated architecture, the Haas technology serves as the high-efficiency upper stage mounted above the eco-friendly steam launch boosters.

(Below: Technical diagrams depicting the three configuration variations of the Haas rocket integrated with Launch Assist System boosters for enhanced orbital capability.)