Nearly a year after NASA’s helicopter “Ingenuity” crashed on Mars, engineers have identified what they believe went wrong on its final flight.
NASA’s Ingenuity was designed as a technology demonstration experiment to see if the four-pound helicopter could fly in Mars’s thin atmosphere, which is about 1 percent of the density of Earth’s. The rotorcraft became the first powered, controlled aircraft on another planet.
At first, Ingenuity was scheduled to perform five test flights over 30 Martian days but ended up surpassing all expectations during its almost three-year operation. The helicopter landed on Mars in February 2021 attached to the undercarriage of NASA’s Perseverance rover and took its first flight two months later. According to a Wednesday statement by NASA’s Jet Propulsion Laboratory, the aircraft flew more than 30 times farther than planned and amassed more than two hours of flight time. After four test flights, Ingenuity served as an aerial scout for Perseverance scientists and rover drives on Mars.
During its 72nd and final flight on Jan. 18, Ingenuity climbed to 40 feet above the Martian surface and hovered for 4.5 seconds before descending at a velocity of 3.3 feet per second. After 32 seconds, the helicopter was back on the surface and had ceased navigation communications with the rover.
Engineers from NASA’s Jet Propulsion Laboratory (JPL) and AeroVironment engineers completed an investigation and determined that Ingenuity crashed due to an issue with its navigation system.
“When running an accident investigation from 100 million miles away, you don’t have any black boxes or eyewitnesses,” Ingenuity’s first pilot, Havard Grip of JPL, said in the statement. “While multiple scenarios are viable with the available data, we have one we believe is most likely: Lack of surface texture gave the navigation system too little information to work with.”
Ingenuity’s navigation system used a downward-facing camera designed to track visual features on the surface over well-textured but flat terrain, the statement said.
The investigation found that during Flight 72, which was carried out in a region of the Jezero Crater filled with “steep, relatively featureless sand ripples,” the helicopter’s navigation system could not determine “enough surface features to track”—which caused the aircraft’s navigation system failure and “created high horizontal velocities at touchdown.”
“In the most likely scenario, the hard impact on the sand ripple’s slope caused Ingenuity to pitch and roll,” NASA said.
The crash resulted in four rotor blades snapping off at their weakest points, with one blade completely separating from the helicopter. This led to an excessive power demand that caused the loss of communication, according to the statement.
Although Ingenuity can no longer fly, the helicopter continues to deliver weather and avionics test data to the Perseverance rover around once a week.
“The avionics data is already proving useful to engineers working on future designs of aircraft and other vehicles for the Red Planet,” NASA said.
On Wednesday, Ingenuity’s project manager, Teddy Tzanetos, shared details on NASA’s Mars Chopper rotorcraft during a briefing at the American Geophysical Union’s annual meeting in Washington.
The concept, researched by Tzanetos and other Ingenuity alumni, is a “more capable” version of NASA’s Ingenuity Mars helicopter. Although the Chopper is in its early conceptual and design stages, the agency revealed that it will be about the size of an SUV—and approximately 20 times heavier than Ingenuity—with six rotors, each with six blades. The Chopper could fly more scientific equipment and explore remote Martian locations while traveling up to two miles in a day.
“Ingenuity has given us the confidence and data to envision the future of flight at Mars,” Tzanetos said.