Astoundingly, we have flown a helicopter on Mars. Aptly christened “Ingenuity,” its relatively modest size belies its colossal achievement in being the first powered aircraft to fly on another world, and that within an unforgiving environment radically different from our own.
Borne to our planetary neighbor slung underneath the Perseverance rover (NASA Jet Propulsion Laboratory’s latest Martian surface explorer), Ingenuity had to be designed to withstand the heavy physical stresses of a rocket launch. Such tolerances aren’t a requirement for standard helicopters. Hence its build is solid, yet lightweight at a mere four pounds.
Though Martian gravity is only just over one-third what we experience on Earth, meaning Ingenuity has less of its own weight to overcome to achieve flight, the Red Planet’s atmosphere is composed almost solely of carbon dioxide and is far thinner than the air to which we’re accustomed. Mars’ atmospheric density is a fraction of Earth’s.
Any run-of-the-mill helicopter would be unable to raise itself even an inch off Martian soil with such a lack of airborne material upon which its spinning rotors might push. Ingenuity therefore generates lift with rotors that spin ten times more rapidly than regular helicopters, rotating about 70 percent the speed of sound at their tips.
While Ingenuity’s spiderlike frame is four feet wide and just over a foot and a half tall, its fuselage is considerably more diminutive. Packed within that space, however, are all the avionics, sensors, cameras, solar-rechargeable batteries, electronics radiation shielding, and cold-combatting heaters it needs to function in its mission as it scouts surrounding Martian terrain for Perseverance to explore.
A fundamental limitation of physics complicates Ingenuity’s operations: the speed of light. Communication with JPL occurs through relays with Perseverance and spacecraft in orbit around Mars, but these signals travel at 186,000 miles per second, while Mars is currently almost 200 million miles away.
This results in a roughly 18 minute delay between the time mission controllers send signals and Ingenuity’s antennas receive them, and vice versa. In light of such lag, Ingenuity cannot be flown in real-time like a drone. After it receives flight programs from control, Ingenuity flies on its own, and JPL staff wait it out to confirm everything has gone according to plan.
To date those plans have been successful, and even surpassed. As of year’s end, Ingenuity had completed 18 flights, attaining altitudes of nearly 40 feet and horizontal distances of over 2,000 feet with future flights expected to be carried out every two to three weeks.
Its technical demonstration phase completed in spring of 2021, Ingenuity has, ahead of schedule, moved on to an operations demonstration phase throughout which its capabilities will be stretched in hopes of gleaning insight into future extraterrestrial powered atmospheric flight.
Ingenuity – the first of its kind – has performed beyond expectations, and JPL has extended its mission indefinitely. Included in her construction was a bit of wing fabric from the 1903 Wright Flyer; she’s done them, and us, justice. Here’s to firsts and taking to alien skies.