Farewell to Ingenuity, NASA’s Plucky Mars Helicopter

NASA’s Ingenuity helicopter has made its last flight on Mars. The plucky technology demonstrator that engineers were not sure would fly at all in the thin Martian atmosphere made 72 flights over almost three years. A damaged rotor blade brought an end to its flying days.

NASA knew something was wrong when they briefly lost communications with the 4-pound (1.8-kilogram) helicopter on that last flight on January 18. Today, the Jet Propulsion Laboratory (JPL), which manages the program, released an image of the shadow of one of the rotor blades showing the damage.

Teddy Tzanetos, Ingenuity Project Manager at JPL, told reporters today the rotor blades must be perfectly balanced for the helicopter to fly. They don’t know if other rotors were damaged, but even if they weren’t, with 25 percent of one rotor missing the helicopter would shake apart. The blades spin at 2,537 revolutions per minute. He said the team was going to try and spin the blades “as best they can and try to get images of the other side,” but it’s likely other blades were affected.

Ingenuity was launched along with the Mars Perseverance rover on July 30, 2020. They landed on February 18, 2021 and Ingenuity made its first flight on April 19, 2021.

Engineers were elated when it lifted off and ascended 10 feet (3 meters) since it wasn’t clear it would be able to fly at all. The density of Mars’ atmosphere is less than 1 percent that of Earth.

The hope was that it could make five flights over 30 days. Then the Perseverance rover would move away and get to work on its main task of collecting samples for later return to Earth.

But Ingenuity proved to be the “little engine that could” and soon received a new assignment — a scout for the rover. Almost three years and 72 flights later, it now has reached the end of the road.

Tzanetos explained Ingenuity was flying over featureless terrain and had encountered problems on the previous two flights, 70 and 71.  On flight 71, the helicopter itself declared an emergency and landed. The last flight was a “pop-up” flight for 30 seconds to determine exactly where it was.

As planned, it rose to 40 feet (12 meters) and hovered before starting its descent. About 3 feet (1 meter) above the surface, communications were lost with the Perseverance rover, which serves as a relay back to Earth.

Communications were restored the next day and NASA still does not know exactly what happened, but the imagery showing the damaged rotor blade brought an end to the mission.

The helicopter navigates using data from a downward-looking camera. Håvard Grip, Ingenuity’s chief pilot emeritus, said the onboard computer looks at the images and sees “good features” and “bad features” and develops a consensus on where to go. “The danger is when you run out of features … you’re not really able to establish what that consensus is and in the end track the wrong kinds of features and that’s when things can get off track.” Although the loss of communications during those critical moments of descent means they’ll never know for sure, he thinks the helicopter became confused and thought it was moving away horizontally from where it was supposed to land and “made an aggressive maneuver” that led to the damaged rotor blade.

Tzantos noted that this evening marks the 1,000th sol — a Martian day, slightly longer than an Earth day — since Ingenuity’s first flight, an appropriate milestone for the mission to come to an end.

NASA Administrator Bill Nelson paid tribute to Ingenuity in a viedo posted to X.

NASA’s historic Ingenuity Helicopter has taken its last flight on Mars. After 72 incredible flights, that remarkable helicopter flew farther and higher than we ever thought possible. #ThanksIngenuity pic.twitter.com/eYwO9R6LY1

— Bill Nelson (@SenBillNelson) January 25, 2024

Ingenuity was designed as a technology demonstration. Lower cost and higher risk than the Perseverance rover, which does not need Ingenuity to accomplish its goals, the helicopter’s purpose was simply to demonstrate that aerial flight on other worlds is possible.

Lori Glaze, director of NASA’s planetary science division, said Ingenuity “shattered our paradigm of exploration, introducing this new dimension of aerial mobility.”  She and JPL Director Laurie Leshin both described today as “bittersweet” — sad to see the end of Ingenuity’s flights, but delighted with all it accomplished.

Both cheered NASA’s technology demonstration programs. Though higher risk, they open opportunities for the future. A chief tenet is that tech demos “do no harm” to the primary mission, which in this case is Perseverance’s collection of Mars samples. Although Ingenuity helped Perseverance by scouting ahead, its absence will not detract from the science mission.

NASA and the European Space Agency are planning a Mars Sample Return mission to bring the samples back to Earth. The most recent design of the MSR mission involved sending two more helicopters to Mars derived from Ingenuity.  Asked what lessons were learned from Ingenuity applicable to those helicopters, however, Glaze demurred, saying only that the entire plan — or “architecture” — for MSR is under review based on the findings of an independent review last year.

NASA does have another aerial mission under development for sure.  Dragonfly is a rotorcraft that will fly over the dunes of Saturn’s moon Titan.