NASA's Mars helicopter Ingenuity encountered some trouble on its latest Red Planet flight, but the little chopper soldiered through.
Ingenuity lifted off May 23 at around 1:20 a.m. EDT (0520 GMT; 10:20 p.m. PDT on May 22; 12:35 local mean solar time on Mars) on its sixth sortie overall and the first flight of its extended mission on Mars, which aims to showcase the scouting potential of Red Planet rotorcraft.
The flight plan called for the 4-lb. (1.8 kilograms) copter to attain an altitude of 33 feet (10 meters), cruise 492 feet (150 m) to the southwest, then move 49 feet (15 m) to the south while snapping photos toward the west, and then zip 164 feet (50 m) to the northeast before touching down.
Things went well at first. But 54 seconds into the flight, Ingenuity suffered a glitch that interrupted the flow of images from its navigation camera to its onboard computer, Ingenuity chief pilot Håvard Grip, of NASA's Jet Propulsion Laboratory in Southern California, wrote in an update on Thursday (May 27).
"This glitch caused a single image to be lost, but more importantly, it resulted in all later navigation images being delivered with inaccurate timestamps," Grip wrote.
"From this point on, each time the navigation algorithm performed a correction based on a navigation image, it was operating on the basis of incorrect information about when the image was taken," he explained. "The resulting inconsistencies significantly degraded the information used to fly the helicopter, leading to estimates being constantly 'corrected' to account for phantom errors. Large oscillations ensued."
Ingenuity pitched and rolled more than 20 degrees at some points during the flight, Grip wrote, and experienced spikes in power consumption. But the helicopter managed to power through the anomaly, eventually landing safely within about 16 feet (5 m) of its intended touchdown spot.
"In a very real sense, Ingenuity muscled through the situation, and while the flight uncovered a timing vulnerability that will now have to be addressed, it also confirmed the robustness of the system in multiple ways," Grip wrote.
"While we did not intentionally plan such a stressful flight, NASA now has flight data probing the outer reaches of the helicopter’s performance envelope," he added. "That data will be carefully analyzed in the time ahead, expanding our reservoir of knowledge about flying helicopters on Mars."
Ingenuity landed on Mars with NASA's Perseverance rover on Feb. 18. They touched down inside Mars' Jezero Crater, which harbored a lake and a river delta in the ancient past. On April 3, the helicopter deployed from the rover's belly, kicking off a month-long, five-flight campaign designed to demonstrate that powered aerial flight is possible on the Red Planet.
That historic campaign went very smoothly, and Ingenuity remained in good health at its conclusion. So NASA approved a mission extension, during which the chopper will perform more directed scouting work.
Perseverance documented Ingenuity's first five flights but did not do so for the May 23 sortie. The rover is now starting to focus on its own science mission, which involves hunting for signs of long-gone Mars life and collecting samples for future return to Earth.
Mike Wall is the author of "Out There" (Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for alien life. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook.