Clever, little Mars helicopters can, no more.
At least one rotor broke during the robotic flying machine's most recent flight last week, NASA officials announced Thursday. Ingenuity is in contact with its companion, the Perseverance rover, which is probing the dry river bed for signs of extinct Martian life.
Intelligence will now lag behind.
“It's bittersweet for me to announce that the brilliant, little helicopter — and it kept saying, 'I think I can, I can' — well, it's now made its last flight on Mars,” announced Bill Nelson, NASA administrator. A video message was posted on X.
In February 2021, Intelligence arrived on Mars in the undercarriage of the Perseverance rover. The helicopter was a late addition to the mission, a demonstration of low-cost, high-risk, high-reward technology, using many off-the-shelf components, which was crucial. Lessons for future mission designers during its 72 flights through the planet's thin atmosphere.
“They can count on what we've achieved,” Theodore Tzanetos, intelligence program manager, said at a news conference Thursday evening. “They can point out that a cell phone app from 2015 can survive the radiation environment on Mars for two and a half years. Lithium-ion battery cells that are commercial, can survive two and a half years off the shelf, and are huge successes for engineers around NASA.
On April 19, 2021, Intelligence became the first plane or helicopter to land on another planet, with the plane's rotors spinning 2,400 times a minute to generate enough lift in an atmosphere only one-hundredth the density of Earth. NASA officials called the flight a “Wright Brothers moment” for planetary exploration.
Five flights in 30 days: The plan is to conduct a demonstration of the novel technology.
Persistence let go of intelligence and began to study the ancient sedimentary rocks at the edge of the Jezero Crater that held the water lake billions of years ago.
Ingenuity went on five flights, and it worked so well that mission managers decided to bring in a helicopter to search the terrain in front of the rover. Over the next thousand days, intelligence went up and down, up and down, and up and down. It encountered problems en route, making three emergency landings. It also survived dust storms and the cold Martian winter, something no spacecraft was designed for. Engineers improved its software so that intelligence could choose its own landing sites.
“To say it exceeded expectations is almost an understatement,” said Lori Glaze, associate administrator of NASA's Science Directorate.
The helicopter team initially prepared for what it described as a 30-day sprint. It turned into an open-ended marathon. Mr. Tzanetos said they realized each day could be their last. But the helicopter always seemed to rise to any challenge and perform well.
Apart from a nonessential sensor that failed, “the rest of the subsystems, from the solar panels to the battery, are significantly aged,” Mr. Tzanedos said. “Our electronics, avionics, processor are all working fine.”
On January 18, during its 72nd flight, the Intelligence did not make contact with the Persistence during landing. Communications were re-established the next day, but a shadowy photograph sent a few days later revealed a quarter of one of the rotor blades had broken off.
“There was an initial moment, obviously, of being sad to see that photo pop up on the screen, confirming what happened,” Mr. Chanedos said. “But that was replaced very quickly with joy and pride and a sense of celebration that we pulled through.”
As intelligence is abandoned on the Martian surface by persistence, Mr. Tzanedos noted.
“She chose the perfect time to end her mission here,” he said.
Ingenuity was flying over terrain he described as “some of the most challenging” — not because of obstacles, but because it's so smooth, with few rocks or other features. The previous flight ended with an emergency landing because the navigation system had trouble tracking its position.
The 72nd flight was scheduled for a 30-second up-and-down to check that everything was working, but again the flat terrain caused problems. Mr “That would have resulted in a power brownout, which would have caused a loss of communication.”
If at least part of one blade breaks, the helicopter cannot generate enough lift and the rotor is unbalanced, meaning the helicopter may shake itself if it tries to take off again.
“We have some lessons in that,” said Howard Cribb, chief pilot for Ingenuity. “We now know that that kind of terrain can be a trap for a system like this.”
A high-resolution camera that can pick out more detail, even in bland terrain, would have helped, Dr. Cripp said.
The Ingenuity team will conduct some final tests on Ingenuity's systems and download the remaining images and data into the helicopter's memory.
NASA engineers are investigating what caused the communication failure and whether a rotor blade hit the ground when the intelligence landed.
Future Mars helicopters are in the planning stages, including a pair that could bring rock and soil samples back to Earth. But the prototype mission to Mars, which has faced technical and budgetary challenges, is being reconsidered, and the helicopters may be abandoned.
“Intelligence is based on principles,” Mr. Tzanedos said. “We now have the facts, and future aircraft designs will rely on all the data we've gathered from Ingenuity.”
