We’re beyond stoked about the upcoming launch of the Perseverance rover to Mars, but NASA’s new explorer won’t be alone on its journey. Tucked beneath its belly is a tiny helicopter named Ingenuity, which will hopefully be the first aircraft to take flight on an alien world.
Perseverance and Ingenuity are scheduled to launch on Thursday, July 30 at 7:50 a.m. ET (4:50 a.m. PT). The NASA Mars 2020 rover and helicopter are expected to land at Jezero crater in February 2021, with deployment of Ingenuity happening a few months after that. Knock on wood, it’ll be the first human-made aircraft to attempt controlled flight on another planet.
This tiny, bare-boned vehicle is what NASA calls a technology demonstrator. The space agency wants to put this concept to the test and use the experience to develop more ambitious projects. Previous tech demos include the 1997 Mars Pathfinder rover and the 2018 Mars Cube One nanosatellites—the smallest machines to zip past a planet.
Writing in an outline presented at the 2018 AIAA Atmospheric Flight Mechanics Conference, project engineers described amped-up versions of the rotorcraft concept:
They could access and land at designated targets in a controlled manner and could be used to carry or retrieve small payloads. Helicopters could enhance rover missions by quickly scouting out safe traverse routes or providing reconnaissance on possible science target destinations and, as standalone systems, could be used to explore areas that may not be reachable by rovers. Mars helicopters may also be considered as elements of a sample return architecture where they could be used for timely retrieval of small science samples back to a Mars ascent vehicle for return to Earth.
Before we get to that stage, however, NASA will have to evaluate Ingenuity’s performance on Mars. Over the course of a 30-day period, the helicopter will perform as many as five flight tests, none of which will last longer than 90 seconds. Ingenuity will ascend anywhere from 10 to 33 feet (3 to 10 meters) above the surface and traverse up to 980 feet (300 meters) during each flight, according to NASA. The robotic helicopter will be capable of autonomous flight and will communicate with Perseverance after landing.
With a fuselage roughly the size of a softball, Ingenuity weighs just 4 pounds (1.8 kg). Its two rotary blades, which rotate in opposite directions, measure 4 feet (1.2 m) long. The rotorcraft is equipped with an antenna, four landing legs, and a solar panel for recharging its batteries.
A critical phase of the mission will happen when Perseverance deploys the helicopter to the Martian surface. To move the helicopter from the belly of the rover to the ground, NASA developed the Mars Helicopter Delivery System, as the space agency explains:
On around the 60th Martian day, or sol, of the mission, Perseverance will drop the Mars Helicopter Delivery System’s graphite composite debris shield that protected the helicopter during landing. Then it will drive into the center of the chosen airfield. About six days later, after the helicopter and rover teams are satisfied everything is go, they’ll command Mars Helicopter Delivery System to do its thing.
The deployment process begins with the release of a locking mechanism that keeps the helicopter in place. Then a cable-cutting pyrotechnic device fires, allowing a spring-loaded arm that holds the helicopter to begin rotating Ingenuity out of its horizontal position. Along the way, a small electric motor will pull the arm until it latches, bringing the helicopter body completely vertical with two of its spring-loaded landing legs deployed. Another pyrotechnic fires, releasing the other legs.
After this point, the helicopter will finally be released, requiring the machine to survive a 5-inch drop to the surface. Given the weaker pull of gravity on Mars compared to Earth, that should be a breeze. Around a week later, assuming all looks good, Ingenuity will perform its first test flight.
Technically, the helicopter has already logged 75 minutes of flight time, or, more accurately, a model of the helicopter logged this flight time on Earth during NASA tests between 2014 and 2019. Obviously, Mars and Earth have very different environments, requiring the space agency to get creative with the experimenting.
For example, Mars has an atmosphere that’s 100 times thinner than Earth’s, so there’s not a lot of air to provide the much-needed lift. To take flight, Ingenuity will spin its rotors at 2,400 rpm, which is considerably faster than the rotors on a conventional helicopter.
To simulate the conditions found on Mars, NASA engineers sucked all the gases from a 25-inch-wide (64-cm) vacuum chamber and added some carbon dioxide. A model of the rotorcraft managed to sustain flight for around a minute, hovering above the ground at an altitude of 2 inches (5 cm). It was a small leap for the helicopter but a giant leap for the developers.
Also, because the gravity on Mars is about 38% of the surface gravity on Earth, the 4-pound helicopter will weigh just 1.5 pounds (0.68 kg) on the Red Planet. During development, the model was tested with a system that simulates reduced gravity, and it performed well.
Ingenuity will also have to endure some serious temperature swings, as nighttime temperatures can get as cold as -130 degrees Fahrenheit (-90 degrees Celsius). The helicopter has 1,500 different components made from aluminum, silicon, carbon, foil, and foam, which will continually expand and contract during the course of its mission. Ingenuity was designed with these temperature swings in mind, but we’ll have to wait and see how it performs in when it’s actually on the Red Planet.
Ingenuity won’t be carrying any scientific instruments, but it has autonomous capabilities. Due to communication delays from Earth to Mars, the helicopter will have to fly on its own and choose sensible places to land.
The Ingenuity project is a small start, but success will lead to bigger, better things. Years from now, when aircraft of various sorts dart above the Martian surface (and possibly even other planets), we can look back on this pioneering helicopter as the craft that made it all possible.