Vertiflite May/June 2021

With the help of the Mars Helicopter Delivery System, Ingenuity’s legs were extended so the drone could be dropped the final inches to the Mars surface.

“We are in uncharted territory, but this team is used to that,” explained Aung, who has been with the Ingenuity program since its inception. “Just about every milestone from here through the end of our flight demonstration program will be a first, and each has to succeed for us to go on to the next.” Members of that pre-flight press briefing team included Lori Glaze, Director of NASA’s Planetary Science Division, NASA Headquarters; Bobby Braun, Director for Planetary Science, JPL; J. (Bob) Balaram, Ingenuity chief engineer, JPL; and Farah Alibay, Perseverance integration lead for Ingenuity, JPL. Alibay noted the risks before deployment. “Once we start the deployment there is no turning back,” she said prior to the task. “All activities are closely coordinated, irreversible and dependent on each other. If there is even a hint that something isn’t going as expected, we may decide to hold off for a sol or more until we have a better idea what is going on.” After it dropped Ingenuity, Perseverance drove 16 ft (5 m) away and verified that the rotorcraft and rover were communicating via their onboard radios. Balaram said before this final task, “Once we cut the cord with Perseverance and drop those final five inches to the surface, we want to have our big friend drive away as quickly as possible so we can get the Sun’s rays on our solar panel and begin recharging the batteries.” Everything went as planned. No problems were reported by mission control. Now released, Ingenuity is powered solely by its solar array. Lift Off! Although NASA had initially announced a launch date of April 11, checkout tests two days before revealed a problem. On April 12, JPL announced that it had come up with a “software solution for the command sequence issue identified on Sol 49 (April 9) during a planned high-speed spin-up test of the helicopter’s rotors… This software update will modify the process by which the two flight controllers boot up, allowing the hardware and software to safely transition to the flight state.”

After dropping off the helicopter, the rover retreated 211 ft (64 m) away to the Van Zyl Overlook, noted here as the twitcher’s point (a reference to birding).

Finally, on April 19, everything was ready.

As planned, the solar-powered helicopter became airborne at 3:34 a.m. EDT (GMT-4)—12:33 Local MeanSolarTime—to take advantage of the Martian noon for optimal energy and flight conditions. Altimeter data indicated Ingenuity climbed to its prescribed maximumaltitude of about 10 ft (3m),maintained a stable hover for about 5 seconds, pivoted about 96 degrees and hovered for another 20 seconds. It then descended, touching back down on the surface of Mars after logging a total of 39.1 seconds of flight. After the data was transmitted from the helicopter to the rover, it was then beamed back 173 million miles (278 million kilometers) to Earth, where JPL confirmed at 6:45 a.m. EDT to the millions around this world who were waiting to hear about the first flight on another world. “From everything we’ve seen so far, it was a flawless flight,” Grip said. “It was a gentle takeoff, at altitude, it gets pushed around a little bit by the winds, but it really just maintained station very well, and it stuck the landing, right in a place where it was supposed to go.” The first three flight tests are to focus on basic hover and flight capabilities. The helicopter will eventually fly as far as 160 ft (50 m) downrange and back to the starting point. Each flight is not expected to exceed 90 seconds. While Ingenuity is designed to survive windstorms, the team isn’t planning to fly in high wind or dusty conditions, said Ravich. Perseverance has equipment onboard to alert mission control of any weather anomalies.

May / June 2021

Materials that Ravich shared with Vertiflite indicated that, based on the Earth-based testing and simulation that NASA JPL had

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