Earth is the only planet in the solar system with airplanes that allow permanent flight. Suppose the groundbreaking Ingenuity helicopter currently stowed aboard the similarly spectacular Mars Perseverance rover completes its scheduled mission. In this case, Mars will be the second planet on which a powered airplane flies through the atmosphere.
Ingenuity sent its first status report since landing on Mars. The signal, which arrived via the legendary Mars Reconnaissance Orbiter (MRO), reports on the condition of the helicopter’s batteries and the operation of the base station, which, among other things, operates the heaters that are important for the electronics within an acceptable temperature range. Fortunately, all of this is good news at the moment as the batteries and base station are working as expected.
Artist’s impression of ingenuity over Mars with the Perseverance Rover in the background. Credit NASA / JPL – Caltech
While Ingenuity hasn’t made a flight (hopefully this will soon become an outdated statement), the helicopter has already overcome some daunting challenges. Perhaps the most dangerous part of Ingenuity’s journey was the interplanetary journey from Earth to Mars as part of the larger Perseverance rover mission. Perseverance was launched in July 2020 and landed in Jezero Crater on Mars on February 18. A new high-resolution video of Perseverance’s spectacular Sky Crane landing was released today by NASA and is stunning in itself.
The endurance is lowered to the surface of Mars by the “sky crane”. Note that this is NOT an artistic impression, but an actual photo from the February 18th landing. Credit NASA / JPL-Caltech
It’s easy to miss how difficult it is to land on Mars. The alarming fact is that only about half of the Mars missions made it successfully! One of the main reasons for this is the density of the Martian atmosphere. Fortunately, Ingenuity survived the dangerous descent from space when it was strapped to the rover’s belly.
One of the main obstacles to landing on Mars will continue to cause problems for our heroic helicopter as it is safe on the surface. The atmospheric pressure on the surface of Mars is only about 1% of the earth’s pressure. The summit of Mount Everest is only a third of the atmospheric pressure of sea level. While this is believed to be at the limit of what humans can survive (or, unfortunately, beyond in some cases), it is well beyond the reach of terrestrial helicopters. If you’ve ever wondered why wealthy explorers don’t just cheat and fly to the top of Everest in a helicopter, this is why!
Compared to Mars, the air on Everest might as well be pea soup. The ridiculously diluted air on Mars makes the helicopter flight extremely challenging. Ingenuity spins its two counter-rotating rotors five times faster than terrestrial helicopters, about forty times per second. Ingenuity is also light, only about 1.8 kilograms. The rotors are approximately 1.2 meters in diameter and relatively oversized to maximize lift.
Fortunately, Mars Ingenuity is taking a break in one area. Mars has only about a third of the surface gravity of the earth. If you were to keep the plane on earth, it would feel about as heavy as a two-liter bottle (with a few sips, thankfully). On Mars, the exact same airplane would feel like a 20-ounce (591 milliliter) bottle.
NASA / JPL video of the Ingenuity helicopter mission
The helicopter does not play a crucial role in the scientific mission of perseverance. It is essentially a technological demonstration or a proof-of-concept. The data collected by Ingenuity will be used to develop future Martian aircraft. It’s solar powered and has electronics that have been miniaturized to keep everything light enough for flight.
Ingenuity is also completely autonomous. Because of the extreme distance to Mars, the helicopter mission leaders cannot fly the aircraft in real time the way terrestrial drone pilots can use joysticks to maneuver at home. The time it takes for a signal to travel from Earth to Mars is longer than the total flight time of the helicopter! Imagine driving a car (on a closed circuit only in your imagination) and when you turn the wheel the car runs out of gas before registering your input!
Ingenuity in front of the Mars Perseverance Rover. Credit NASA / JPL-Caltech
If Ingenuity successfully demonstrates aerodynamic powered flight on Mars, it will be a milestone that is second to none. One can only imagine the effects that flying Mars explorers could have on future missions. A future helicopter could work with a larger rover and act as a scout, carefully monitoring the terrain and helping the parent rover more efficiently plan a safe and scientifically interesting course. Perhaps a helicopter could take samples from a wide area and deliver them to a rover or a stationary facility using sophisticated scientific instruments. Even a stand-alone helicopter mission could be designed. There are many cliffs, ice caps, volcanoes or otherwise inaccessible parts of the Martian landscape that are likely to be permanently inaccessible to ground rovers or even humans.
The coming weeks will be one of the most exciting periods for fans of space exploration, aviation or anyone who is amazed by exceptional engineering achievements and of course the ingenuity of the brilliant scientists and engineers who built Ingenuity.
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Perseverance mission page
Ingenuity Mission Page