NASA's Ingenuity Helicopter Crash: Why did the Mars Accident Happen?

Months after NASA's Ingenuity Mars Helicopter crash-landed into the dusty surface of Mars, scientists have finally figured out what went wrong. Ingenuity was the first aircraft to ever fly on another planet, sadly crashing to the ground during its 72nd flight on January 18 this year. Engineers from NASA's Jet Propulsion Laboratory in Southern California and AeroVironment—who helped build the helicopter—have been investigating the cause of the crash ever since and have now concluded that it was due to an issue with the on-board navigation sensors.

Ingenuity was launched to Mars alongside the Perseverance rover in July 2020, landing in Mars' Jezero Crater in February 2021. The helicopter was originally only planned to operate for 30 days, taking up to 5 test flights, but engineers were delighted to find that Ingenuity carried on functioning long past this deadline. In total, Ingenuity operated for nearly three years, flying over 30 times further than initially planned during its 72 total flights. According to NASA engineers, Ingenuity's final flight came to a sticky end after its navigation sensors failed to discern enough detail from the smooth Martian surface for it to accurately calculate its position. This resulted in the helicopter landing while moving horizontally at high speeds, which ended up snapping all four of the craft's rotors. "When running an accident investigation from 100 million miles away, you don't have any black boxes or eyewitnesses," Håvard Grip, a Jet Propulsion Laboratory engineer and Ingenuity's first pilot, said in a 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."

Engineers pieced together the details of Ingenuity's swan song using the limited data transmitted back to Earth, alongside satellite images of the crash site. They found that Ingenuity climbed to 40 feet and hovered to take photos, before beginning its descent at 19 seconds. By the 32-second mark, the helicopter had crashed into the ground. The helicopter's navigation system watches the ground using a down-facing camera, which it uses to track visual features on the Martian surface. During its early flights, Ingenuity could determine its position using the flat textured rocky surface, but its later flights were over an area of ground characterized by smooth, steep sand ripples. After its take off, Ingenuity's cameras likely couldn't spy enough features on the ground to accurately track its location, causing it to land at a high horizontal velocity, pitching and rolling so vigorously all its rotors snapped, and it lost communication with Earth. "Because Ingenuity was designed to be affordable while demanding huge amounts of computer power, we became the first mission to fly commercial off-the-shelf cellphone processors in deep space," Teddy Tzanetos, Ingenuity's project manager, said in the statement. "We're now approaching four years of continuous operations, suggesting that not everything needs to be bigger, heavier and radiation-hardened to work in the harsh Martian environment." Despite it having landed on the Red Planet for the final time ever, Ingenuity still sends weather data back to Earth via the Perseverance rover. It also beams home avionics test data, which could hopefully help engineers design other aircraft for future Mars missions. NASA recently announced they were designing a larger "Mars Chopper" aircraft, which will be 20 times heavier than Ingenuity and travel as far as 2 miles each day. "Ingenuity has given us the confidence and data to envision the future of flight at Mars," Tzanetos concluded. Do you have a tip on a science story that Newsweek should be covering? Do you have a question about Mars? Let us know via science@newsweek.com.