One giant hover for aviation… NASA’S next red rover will be a helicopter and the first deployed on another planet.
The reality is far less convincing than the movie-like concepts NASA have released [photo above] and no – you can’t fly it, but nevertheless, we are on the way towards seeing helicopters and drones flying reconnaissance missions on Mars.
In 2020 the first Mars Helicopter will hitch a ride to Mars inside the belly of a six-wheeled rover, before being set free to perform a controlled flight within the atmosphere and NASA already has plans for more ambitious missions in the future as low-flying scouts and aerial vehicles to access locations not reachable by ground travel.
Developing the Mars Helicopter
Development on the Mars Helicopter started in 2013 when NASA’s Jet Propulsion Laboratory (JPL) first began work on the technology development that’s made the first Mars Helicopter a reality.
Gravity on Mars is roughly 38 percent of Earth’s which presented the scientists and engineers at JPL a real challenge. The altitude record for a helicopter flying on Earth is about 40,000 feet, but when the Mars Helicopter is on the Martian surface, it’s already at the Earth equivalent of 100,000 feet up. “To make it fly at that low atmospheric density, we had to scrutinize everything, make it as light as possible while being as strong and as powerful as it can possibly be.” said Mimi Aung, Mars Helicopter project manager at JPL.
NASA conceptual video showing the Mars Rover and Mars Helicopter
To keep the aircraft as light as possible (1.8kg) the fuselage was reduced to the size of a tennis ball and it’s twin counter-rotating blades rotate at 3,000 rpm – about 10 times the rate of a helicopter on Earth, benefitting from the reduced air resistance and creating the lift required in the extreme environment.
The chance for NASA to bag another first and maintain their reputation for pushing aerospace boundaries is not lost on Jim Bridenstine, NASA Administrator. “NASA has a proud history of firsts. The idea of a helicopter flying the skies of another planet is thrilling. The Mars Helicopter holds much promise for our future science, discovery, and exploration missions to Mars.”
Testing the Theory
When JPL started developing the Mars Helicopter nobody knew whether the blades could be spun fast enough to support all the other equipment and components it needed to house.
Imprecise rough calculations done over a decade ago had suggested that it was. Interestingly, JPL engineer Bob Balaram had attended a lecture on mesicopters (miniature propeller aircraft about the size of a coin), during which he realised that the Reynolds number; used to express the performance of an airfoil based on the density and viscosity of the air it’s operating in, would be roughly equivalent to a bigger wing operating in thinner air. This lead to the first test being conducted in a 10-foot vacuum chamber with an eight-inch blade rotating at 7,000 rpm in a simulated Martian atmosphere, just managing to produce lift.
Early testing of carbon fibre blades for the Mars Helicopter
The size of the Mars Helicopter has scaled up somewhat with the most recent test hover below showing how far the helicopter has come in its development. Weight was the most important factor at each development stage of the Mars Helicopter however so many laws of physics have to be in balance to achieve stable, controlled flight with so little atmosphere and gravity. For example, creating light carbon fibre rotors reduced the weight but too much, they were too flimsy for the Mars atmosphere which lacks the natural background dampening of Earth’s, meaning resonance built up.
The team has overcome all of these obstacles whilst operating lean and without the big budget of other NASA projects, the helicopter itself is piggybacking on another flagship NASA mission and is more of a tech demo. The hope is that this will eventually lead to a fully funded Mars Helicopter.
With current technology, it is unlikely that a helicopter capable of carrying passengers will ever be able to function in the Mars atmosphere. That being said, Mars has an exciting future with Elon Musk’s Space-X planning to begin a 40-100 year plan to build the first Mars city. It’s exciting to know that the physics supports helicopters on Mars and with the world’s finest engineers working on solutions that benefit the helicopter and aviation industry as a whole we are excited to see how the Mars Helicopter performs in its first Mars mission.