It’s incredible how many different types of rocket engines are being developed simultaneously for use in space exploration. It’s something that shows that, if there was still a need for it, space is where the future of humanity can be found.
In recent years, the biggest players in space exploration have begun investing heavily in the R&D of new rockets and ships that can be reused, lowering the cost of each launch. By now you’ve probably heard of the biggest: SpaceX, Blue Origin, Sierra Space, Axiom Space, and the list could go on and on.
For every space company that has achieved something, there are countless other startups vying to make it in this competitive new world. Among them is a crew called Stoke Space, which this month managed to do something that put it directly under our spotlight.
Stoke Space is a Seattle-based company that was founded just four years ago. The main and stated mission is to provide “cheap, on-demand transportation to, through and from space” by using fully and reusable rockets and space vehicles that can be turned around and sent to new missions at the same frequency that passenger aircraft operate today.
A daring mission, you might say, but one that has attracted the attention of the US Space Force, NASA and the National Science Foundation, organizations that have already funded Stoke’s projects to varying degrees.
To reach a point where it can make good on its word, the company is relying on a rocket called Nova. It is still in development and will be a two-phase system that will be completely reusable, making customer launches of any nature cheap and fast (it remains to be seen exactly how much that will be).
Photo: Stoke Space
The first stage of the Nova will rely on seven liquefied natural gas (LNG) and liquid oxygen (LOX) engines for launch. When the mission to put Phase 2 into orbit is complete, Phase 1 will touch down at the launch site or other location for landing.
The Stage 2, with a fairing on top to carry cargo, should be able to perform unlimited restarts of its engines, meaning it will be able to maneuver between a long list of runways. This too is intended to return Earth in a controlled manner when the mission is over, so that it can fly on more and more missions again.
At the heart of Nova’s Phase 1 booster is a new type of engine that Stoke is currently developing. It’s a piece of hardware of the full-flow, staged-combustion (FFSC) variety, a design that can deliver “unparalleled efficiency and performance.”
It’s the same kind of operation that SpaceX uses for its Raptor engines. Basically, in such engines, the propellant passes through several combustion chambers, and this in turn results in higher fuel efficiency compared to other designs, and a high specific impulse.
Stoke hit the headlines this week after announcing the completion of the first hot fire test of the Nova stage 1 engine. The procedure was performed last week at the company’s facility in Moses Lake, Washington.
During the test, the powerplant was ramped up to take-off power level, going from an idle state to a state where it generated the equivalent of 350,000 horsepower in less than a second. By comparison, the five engines on the first stage of the Saturn V rocket that powered the Apollo Moon exploration program produced the equivalent of 160 million horsepower.
Photo: Stoke Space
Once that point was reached, the engine maintained power levels for an undisclosed period of time and shut down, per test procedures.
What’s impressive about all this isn’t necessarily the heat test or the power generated, but the fact that the engine was put together by Stoke engineers in just a year and a half.
The company claims the successful tests “on track to deliver the most robust, fully and rapidly reusable medium-range rocket in the world.” It’s unclear when we’ll see the rocket in action, as Stoke have never said so publicly.
As for the second stage of the Nova rocket, its ability to take off and land vertically was put to the test last September, and not much has happened on that front since then (as far as we know).
Stoke will continue to subject the FFSC engine to various procedures for the remainder of the year, while simultaneously scaling up operations for the first orbital launch.
When fully operational, the Nova should be able to fulfill missions in a variety of jobs on behalf of both civilian and defense customers. We have no word yet on how much Stoke will charge on average per launch.