Jonas Linell, Copenhagen Suborbitals

Jonas Linell, Copenhagen Suborbitals

Jonas Linell, Copenhagen Suborbitals

Jonas Linell, Copenhagen Suborbitals

Jonas Linell, Copenhagen Suborbitals

The amateur rocket enthusiasts at Copenhagen Suborbitals have been plugging along now for eight years, and after a series of some launch attempts and some failures, the crowdfunded group says it is making progress toward more ambitious goals—including the launch of a human on a suborbital flight.

Founded in 2008, Copenhagen Suborbitals has attempted more than a half-dozen launches of various sized rockets, including the Heat-1X in 2011, believed to be the most powerful amateur rocket ever launched. Most recently, in July, Copenhagen Suborbitals launched its Nexø 1 rocket, a 5.6-meter-long booster weighing 205kg. Powered by liquid oxygen and ethanol, the Nexø only reached an altitude of 1.5km instead of its planned flight to 8km.

Such failures are common in amateur rocketry, and Copenhagen Suborbitals is no exception. However, the Denmark group's ambitions far outstrip those of other amateur clubs. The group says its tests are leading up to development of the Spica rocket, a 13-meter-tall launcher with a liftoff mass of 4,000kg, mostly fuel. The rocket would be powered by an engine with approximately 22,500 pounds of thrust (for comparison, the Mercury-Redstone rocket that launched Alan Shepard on America's first suborbital flight was powered by an engine with 78,000 pounds of thrust).

Suborbital flight

To raise interest in such a mission, Creative Director Jonas Linell released some digital paintings this week of what that flight might look like. The group plans to use the Spica to launch an as-yet unnamed capsule to 100km, just above the Karman line that delineates the edge of space. After a 90-second engine burn, the spacecraft will reach an apogee at about 190 seconds into flight before the capsule returns to Earth.

According to Linell, volunteers are designing the bi-propellant Spica engine, which is significantly larger than any the group has developed before. Additionally, the group is also building a scale model of a capsule to be tested in a wind tunnel sometime in 2017. The year 2017 should see the first metal being cut for the Spica capsule, engine, and rocket, Linell said.

The mission to space is dubbed Spica V, as it would follow Spica I and other uncrewed tests, as well as a crewed Spica IV flight to a lower altitude.

Is this realistic?

As ever, the question surrounding Copenhagen Suborbitals is whether its goals are realistic, given the scale of achievement needed to put a human into space (however briefly) and to bring him or her safely back to Earth. Ars reached out to Communication Director Mads Wilson for some clarification.

Wilson said the first Spica-class rocket will likely cost about $1 to $2 million to develop and build, all of which will go toward materials, as everyone involved in the project works for free. "If we had $2 million now I would estimate about two to three years until the first unmanned flight," he told Ars. "But right now we are raising money as we go along, so the actual time frame is uncertain. Contrary to what one might expect, the rocket itself is actually not as expensive and laborious as all the test and launch equipment needed to test it and ultimately launch it."

Funding issues aside, and despite some of its launch failures, Copenhagen Suborbitals has demonstrated solid technical skills. Early on it made the decision to launch from a mobile platform, Sputnik, out of international waters in the Baltic Sea. This is because, as a non-governmental organization, it would be difficult to find a land-based spaceport and nation willing to grant them launch licenses. Developing the capacity to launch from the sea is not a trivial engineering challenge.

Whether the group ultimately succeeds—or not—the journey represents most of the fun. These are amateurs, solving hard problems, being completely transparent, and it is exciting to watch. This effort is akin to the kind of rocket building you might do in Kerbal Space Program, only in real life, with real people. And if a man or woman ever does clamber into a small spacecraft atop one of their rockets, presumably it will be with eyes wide open.

Listing image by Jonas Linell, Copenhagen Suborbitals