Masten Achieves First Hot-Fire of Broadsword Rocket Engine

Masten Space Systems ©2016

Mojave, CA – On September 30, 2016, Masten Space Systems successfully concluded the 13-month design, build, and test period for the first development unit of the Broadsword 25 rocket engine, funded as a technology demonstration under the Defense Advanced Research Projects Agency (DARPA)’s Experimental Spaceplane (XS-1) program. This first phase of the engine development effort included commissioning Masten’s largest mobile engine test stand and firing of the company’s highest-thrust rocket engine to date.

The Broadsword 25 is a liquid oxygen- and liquid methane-propelled rocket engine with a full-throttle sea-level thrust rating of 25,000 lbf. Masten initiated development of the Broadsword in August 2015, as a cost-effective reusable engine suitable for use in both boost and upper-stage applications.

Broadsword employs a novel dual-expander cycle, which allows high efficiency at sea level while maintaining the benign turbomachinery conditions characteristic of traditional expander cycle engines. It is made primarily via additive manufacturing, or “3D printing”—a technology that enables complex design geometries, reduces part count by an order of magnitude, and compresses manufacturing times, all of which enable rapid engine development.

The goal of this initial hot-fire test campaign comprised ignition and startup sequence development. The effort concluded with demonstrating six successful engine starts. Masten has subsequently begun the design and build of a second development unit, incorporating lessons learned during manufacturing and testing, and plans to proceed with main-stage hot-fire testing in the next phase.

Masten aims to continue Broadsword development over the course of 2017 and 2018 in collaboration with NASA under the Tipping Point program, and anticipates moving into flight qualification after the conclusion of that effort.

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What’s the Point?

That is a question that comes up from time to time when people see Xaero-B and Xodiac. Both vehicles seem to be doing what other rocket companies have already *demonstrated* and to greater lengths at that. The underlying premise of the question is this: you are not seeing anything that hasn’t already been done. And there is some truth to that on the surface, the VTVL part is not any different. It is in this perception of us vs them that the question sort of belies the real activity at hand…..

(Click here to keep reading…) Developing rocket technology is more than a skin deep proposition.

Masten’s Green Bipropellant: MXP-351

As part of our partnership with NASA through the Lunar CATALYST (Lunar Cargo Transportation and Landing by Soft Touchdown) program, we have been actively developing a proprietary new bipropellant – MXP-351. This propellant is intended to be flown on our XL-1 lunar lander which is capable of bringing up to 100 kg (221 lb) softly to the lunar surface. MXP-351 represents the next step in Masten’s internal propulsion development program in improving our capabilities closer towards spaceflight.

MXP-351 is a nontoxic, storable and hypergolic bipropellant combination. These storable propellants, as opposed to cryogenic propellants like Liquid Oxygen or Liquid Hydrogen, are stable for long periods of time at room temperature. Hypergolic propellants mean that the fuel and oxidizer will ignite spontaneously as soon as they come into contact with each other. Storable and hypergolic systems eliminate the need for separate igniter systems and typically only need minimal thermal conditioning of the propellants, improving their reliability and performance. Consequently, such systems are favored highly for in-space missions like the XL-1 lunar lander.

Historically, spacecraft have used cocktails of Hydrazines and Nitrogen Tetroxide (NTO) as storable hypergolic propellants. These propellants have very high performance and were used in the Apollo Lunar Module Ascent and Descent engines, as well as part of the Space Shuttle’s Orbital Maneuvering System (OMS). However, they are both extremely toxic, requiring exhaustive procedures for safe procurement, handling, spill control, and disposal. The nontoxic MXP-351, by comparison, is exceptionally easy to handle. They have very low vapor pressures, meaning they don’t evaporate easily and pose inhalation hazards to any workers. Spills are easily rectified by simply diluting with water and rinsing away. These greatly reduced operational constraints have the potential to reduce recurring costs for spaceflight applications.

More importantly, it allows us to safely and thoroughly test out our propulsion systems here in Mojave with the same regularity as we fly our vehicles. In 2016, we successfully fired the first generation of our 225 lb XL-1 main engine, dubbed ‘Machete’. This simple ‘boilerplate’ engine validated our injector design, performance estimates, and applicability of MXP-351 in a rocket test environment. Future tests with MXP-351 will use additively-manufactured technology to test regeneratively-cooled thrust chambers, as well as scaling up the thrust capability up to 1,000 lb for a terrestrial testbed version dubbed (XL-1T) that is currently in manufacture.

NASA CATALYST has been instrumental in aiding our development in the program, giving advice from industry experts who have worked with similar propellants in the past, as well as providing advanced analytical capabilities to characterize engines with these propellants.