With three successful test flights under their belts, engineers at the Jet Propulsion Laboratory uplinked commands for a fourth, more ambitious flight of the Ingenuity Mars helicopter Thursday, but the small rotorcraft apparently failed to take off, officials said.

“Aim high, and fly, fly again,” JPL tweeted. “The #MarsHelicopter’s ambitious fourth flight didn’t get off the ground, but the team is assessing the data and will aim to try again soon.”

The small 4-pound dual-rotor drone, designed to test the feasibility of powered flight in the ultra-thin atmosphere of Mars, had been scheduled for its most ambitious flight yet, targeting liftoff from “Wright Brothers Field” in Jezero Crater at 10:12 a.m. EDT.

The flight plan called for a climb to an altitude of 16 feet and a 436-foot out-and-back traverse, the farthest to date. Throughout the planned flight, an on-board camera was expected to collect images of the surface every four feet to help the flight computer determine its exact location.

But for reasons that were not immediately known, the helicopter did not take off. Engineers are reviewing telemetry beamed back from Mars to pinpoint whatever the issue might have been and what, if anything, might need correcting before another flight attempt.

NASA science chief Thomas Zurbuchen tweeted that Ingenuity already has “met the goals associated with this technology demo. They have proven it is possible to fly on Mars! The team is looking at the data to assess the latest flight attempt, and I am so proud of what they’ve already achieved.”

Ingenuity captured the world’s imagination with its first flight on April 19, about a month after arriving on Mars with the Perseverance rover. The $80 million drone climbed up to an altitude of about 10 feet, hovered briefly and then landed.

It flew a second time on April 22, climbing to 16 feet and flying about seven feet to one side and then back again. For its third flight on April 25, Ingenuity climbed back up to 16 feet and flew 164 feet down range before returning to its starting point.

Monumental moment: First flight on Mars


“When Ingenuity’s landing legs touched down after that third flight, we knew we had accumulated more than enough data to help engineers design future generations of Mars helicopters,” Bob Balaram, Ingenuity chief engineer at JPL, said in an on-line status report. “Now we plan to extend our range, speed and duration to gain further performance insight.”

But it was not to be, at least not on Thursday.

NASA already planned a news briefing Friday to review the helicopter milestones to date and to unveil plans for a fifth and final test flight before Perseverance moves on with its primary science mission. Engineers may have a better idea by then about what prevented Thursday’s flight.