The Mars Helicopter has been silent for six sols, endangering the Perseverance rover • The Register

NASA disclosed a six-day period during which it was unable to communicate with the Ingenuity Mars helicopter.

in a long time mailTravis Browne, chief engineer, explained that after the helicopter’s 49th flight, radio contact was lost for six sols – just under six days and six hours of Earth time.

At first, NASA’s Mars Arcs wasn’t too concerned. The Perseverance rover moved behind a rocky outcrop creating a “contact shadow”. Brown wrote that since Sol 685, the helicopter had been “unfortunately drifting in and out of stay-at-night mode” which made daily contact with the craft difficult. So a day or two without communication was nothing to worry about.

But once Perseverance moved to another location and Creativity could not be found, “the situation began to cause some anxiety,” Brown writes.

“Poor communications performance was seen as a reasonable explanation, but there were reasons to doubt it,” he wrote. “In the more than 700 sols operating the helicopter on Mars, not once have we witnessed a complete radio blackout. Even in the worst communications environments, we have always seen some indication of activity.”

But the signal received that day, Sol 761, was just an ACK. The next day, the helicopter again acknowledged an command, but did nothing else.

Mission personnel decided that the hills separating creativity from perseverance were a challenge for the helicopter’s radio. It didn’t help that Perseverance’s helicopter base station (HBS) antenna was mounted low to the right of the vehicle and was subject to obstructive effects.

While the NASA folk figured it out, Perseverance moved toward its next goal—but this created new problems.

“It is critically important that Ingenuity stay ahead of Perseverance while navigating the narrow channels of the Jezero Delta,” Brown writes, where the rotorcraft’s job is to pre-explore the wheeled vehicle. And NASA runs a no-fly zone around Perseverance.

With the rover in motion and the helicopter at a halt, it became imperative to stir creativity.

“Drawing on pre-flight checks on board the helicopter to ensure the rover’s safety and relying on solid communications from the rover’s imminent proximity, the team correlated the flight plan,” Brown wrote.

Dexterity did more than just acknowledge that download. She caught it and carried it out, resulting in her 50th flight and a record 18-meter high.

“It would be an understatement to say that the helicopter team was relieved to see the telemetry of the successful flight on downlink Sol 763 the next morning,” Brown wrote.

But, he added, worrying days lie ahead.

“It now appears that the dust covering our solar panel will ensure that Creativity will likely remain in this transition energy state for some time,” he wrote. “This means that, to her team’s chagrin, we’re not done playing this high-stakes game of hide-and-seek with the hilarious little chopper.”

Dexterity last flew on April 22, when she did a 188-meter jump from a height of 12 metres. The aircraft was only designed to fly five times, so it greatly exceeded expectations. ®