Nasa's experimental Mars helicopter Ingenuity hovers above the surface of Mars. Photo / AP
Nasa's experimental Mars helicopter Ingenuity hovers above the surface of Mars. Photo / AP
Nasa's experimental Mars helicopter rose from the dusty red surface into the planet's thin air on Monday, achieving the first powered flight on another planet.
The triumph was hailed as a Wright Brothers moment. The mini 1.8kg copter named Ingenuity, in fact, carried a bit of wing fabric from the 1903 Wright Flyer, which made similar history at Kitty Hawk, North Carolina.
"Altimeter data confirms that Ingenuity has performed its first flight, the first flight of a powered aircraft on another planet," said the helicopter's chief pilot back on Earth, Havard Grip, his voice breaking as his teammates erupted in cheers.
Nasa's experimental Mars helicopter Ingenuity lands on the surface of Mars. Photo / AP
Flight controllers in California confirmed Ingenuity's brief hop after receiving data via the Perseverance rover, which stood watch more than 65 metres away. Ingenuity hitched a ride to Mars on Perseverance, clinging to the rover's belly upon their arrival in an ancient river delta in February.
The US$85 million helicopter demo was considered high risk, yet high reward.
"Each world gets only one first flight," project manager MiMi Aung noted earlier this month. Speaking on a Nasa webcast early Monday, she called it the "ultimate dream".
Aung and her team had to wait more than three excruciating hours before learning whether the pre-programmed flight had succeeded 287 million kilometres away. Adding to their anxiety: A software error prevented the helicopter from lifting off a week earlier and had engineers scrambling to come up with a fix.
Applause, cheers and laughter erupted in the operations centre when success was finally declared. More followed when the first black and white photo from Ingenuity appeared on their screens, showing its shadow as it hovered above the surface of Mars. Next came the stunning colour images of the helicopter descending back to the surface, taken by Perseverance, "the best host little Ingenuity could ever hope for", Aung said in thanking everyone.
Nasa had been aiming for a 40-second flight, and while details were initially sparse, the craft hit all its targets: spin-up, takeoff, hover, descent and landing.
To accomplish all that, the helicopter's twin, counter-rotating rotor blades needed to spin at 2500 revolutions per minute — five times faster than on Earth. With an atmosphere just 1 per cent the thickness of Earth's, engineers had to build a helicopter light enough — with blades spinning fast enough — to generate this otherworldy lift. At the same time, it had to be sturdy enough to withstand the Martian wind and extreme cold.
This illustration made available by Nasa depicts the Ingenuity helicopter on Mars which was attached to the bottom of the Perseverance rover, background left. Image / Nasa via AP
More than six years in the making, Ingenuity is a barebones 0.5 metres tall, a spindly four-legged chopper. Its fuselage, containing all the batteries, heaters and sensors, is the size of a tissue box. The carbon-fibre, foam-filled rotors are the biggest pieces: Each pair stretches 1.2 metres tip to tip.
The helicopter is topped with a solar panel for recharging the batteries, crucial for its survival during the -90C Martian nights.
Nasa chose a flat, relatively rock-free patch for Ingenuity's airfield, measuring 10 metres by 10 metres. It turned out to be less than 30 metres from the original landing site in Jezero Crater. The helicopter was released from the rover onto the airfield on April 3. Flight commands were sent Sunday, after controllers sent up a software correction for the rotor blade spin-up.
The little chopper with a giant job attracted attention from around the world, from the moment it launched with Perseverance last July until now. Even Arnold Schwarzenegger joined in the fun, rooting for Ingenuity over the weekend via Twitter. "Get to the chopper!" he shouted, re-enacting a line from his 1987 sci-fi film Predator.
Up to five helicopter flights are planned, each one increasingly ambitious. If successful, the demo could lead the way to a fleet of Martian drones in decades to come, providing aerial views, transporting packages and serving as scouts for astronauts. High-altitude helicopters here on Earth could also benefit — imagine choppers easily navigating the Himalayas.
Ingenuity's team has until the beginning of May to complete the test flights. That's because the rover needs to get on with its main mission: collecting rock samples that could hold evidence of past Martian life, for return to Earth a decade from now.
Until then, Perseverance will keep watch over Ingenuity. Flight engineers affectionately call them Percy and Ginny. "Big sister's watching," said Malin Space Science Systems' Elsa Jensen, the rover's lead camera operator.
