In April of this year, NASA made history, by proving that it is possible to create and sustain powered, controlled flight on Mars, despite its atmosphere being nearly 100 times thinner than that of Earth, with just one-third of the same gravitational pull.
Ingenuity was sent to the Red Planet aboard NASA’s Perseverance Mars rover in February to complete one mission: prove that it could fly in Mars’ atmosphere, which varies significantly from that of Earth.
Ingenuity is currently considered a demonstrator model that has been sent to prove that flight on Mars is possible, rather than to aid NASA in its current research and exploration objectives on Mars.
As such, should Ingenuity successfully prove this, its performance would help inform decisions on the future use of small helicopters for further exploration of Mars, and ultimately, other planets.
While it may not sound too difficult to produce a helicopter capable of taking flight on Mars, the reality is that this was no small feat for the engineers at NASA’s Jet Propulsion Laboratory (JPL) in California. It ultimately took six years of manufacturing and testing to complete Ingenuity.
The first, and perhaps biggest obstacle to overcome, was the fact that helicopters, generally, need an atmosphere in order to fly. While Mars technically does have an atmosphere, it is far thinner than here on earth.
To counteract Mars’ lack of atmosphere, JPL engineers built two long carbon fibre rotors that spin far faster than traditional helicopter rotor blades. For reference, while most helicopters and drones have rotors that spin at around 400-500 revolutions per minute, Ingenuity’s must spin at about 2,400 revolutions per minute.
While Ingenuity’s design was tested in simulations back on Earth, built to mimic the atmosphere of the Red Planet, NASA’s JPL engineers would not know if they had truly succeeded in accommodating the challenge of Mars’ atmosphere in generating lift until Ingenuity completed its first flight test.
Ingenuity’s first successful flight test on Mars took place on 19 April at 10:46am UTC; the very first time that a powered aircraft had taken flight on another planet.
An artist’s concept of Ingenuity on the surface of Mars before the rotorcraft blasted off into space.
Specs
Ingenuity is a remotely-operated autonomous solar-powered rotorcraft vehicle that boasts twin propellers, and four legs below its metallic body, which carries a number of sensors and cameras to assist its navigation, as well as collect data.
The helicopter weighs a total of 1.8 kilograms here on Earth, however measures just 680 grams on Mars. It can fly up to 5 metres high, and has a range of up to 300 metres per flight.
At its head, Ingenuity holds a solar panel, which charges its Lithium-ion batteries, giving it enough energy to perform one 90-second flight per Martian day. Under its solar panel lives its radio antennas, which allow it to send and receive information from Earth, via its companion, the Mars Perseverance rover and the Mars orbiters.
Below that are its four-foot-long rotors, constructed of carbon fibre foam, which allow it to lift in the thin Martian air. Its rotors spin at higher speeds than would be required on Earth in order to generate lift.
Then comes Ingenuity’s cube-shaped body, which holds its avionics, batteries and cameras. This cube contains the rotorcraft’s computer systems, which had to be purpose-built to be small and light enough for Ingenuity to take flight on the Red Planet.
Ingenuity’s body also contains insulation and heaters to keep its computer and sensor systems warm enough to brave the cold Martian nights. The body also holds Ingenuity’s camera and sensors, which record how fast and far the helicopter is travelling, and in which direction. Its cameras can also capture black and white photos, to send back to Earth.
NASA’s Ingenuity project manager MiMi Aung confirmed that the first rotorcraft flight on Mars was a massive success, and called the accomplishment a “Wright Brothers moment”. “We can now say that human beings have flown an aircraft on another planet.”
An image of Ingenuity captured during its first flight by Mastcam-Z, a pair of cameras aboard the rotorcraft’s companion, NASA’s Perseverance Rover.
An undeniable success – Ingenuity’s first flight
To date, Ingenuity has most definitely lived up to its name. Aside from a few minor glitches, the rotorcraft has continued to perform exactly as programmed.
For its maiden flight, Ingenuity was programmed to simply take off, soar approximately three metres above the Martian ground, hover for around 30 seconds, pivot 96 degrees, and land.
The first data received by NASA headquarters included grainy black and white images taken by Ingenuity of its own shadow below, confirming that the helicopter-like vehicle had successfully taken flight.
While the flight lasted a mere 39 seconds, Ingenuity performed exactly as programmed, which saw the NASA mission managers at its Jet Propulsion Laboratory (JPL) burst into applause upon receiving those first data points.
Shortly after receiving the photos from Ingenuity itself, NASA also welcomed full-colour videos of the display sent from the Perseverance rover.
NASA’s Ingenuity project manager MiMi Aung confirmed that the first rotorcraft flight on Mars was a massive success, and called the accomplishment a “Wright Brothers moment”. “We can now say that human beings have flown an aircraft on another planet,” Aung said.
Meanwhile, Ingenuity’s chief pilot at JPL, Håvard Grip, called the rotorcraft’s performance “flawless”.
“It sounds simple, but there are many unknowns regarding how to fly a helicopter on Mars,” Grip said. “That’s why we’re here – to make these unknowns known.”
NASA and the International Civil Aviation Organisation have officially dubbed the zone upon which Ingenuity took its maiden flight as Wright Brothers Field – Mars’ first airstrip.
Further tests
Following Ingenuity’s first successful flight, the objective for each subsequent flight was to increase the level of difficulty for the little rotorcraft, and test its true capabilities. Just days after the rotorcraft’s first flight, it again took to Martian skies in its second successful flight test, flying higher and farther than it did in its inaugural test.
Ingenuity’s second flight, which occurred on Thursday, 22 April, saw it fly five metres above the Martian surface over Jezero Crater, an area now dubbed Wright Brothers Field. From there, the helicopter hovered, before turning five degrees in order to generate enough thrust from its counter-rotating overhead rotors to move two metres to its side.
The flight lasted 51.9 seconds in total, almost 12 seconds longer than its inaugural test flight.
Ingenuity’s third flight test saw it fly further and faster than ever before, exceeding the parameters of its flight tests on Earth, for a grand total flight time of 80 seconds.
It soared again to five metres high, before flying a total of 50 metres downrange, just over half the length of a football field, reaching a top speed of two metres per second – its highest ever speed.
According to NASA, its JPL-based vacuum chambers, which simulate the atmospheric conditions of Mars, are limited – only providing the helicopter to move no more than around half a metre in any direction, so this third flight allowed NASA to really see what Ingenuity is capable of.
As always, NASA’s Ingenuity team at JPL in southern California were thrilled with the results of the test, with Ingenuity performing exactly as planned.
A bump along the way
The rotorcraft’s first attempt at its fourth test flight saw Ingenuity’s first minor glitch, as the JPL team received data that the machine had failed to execute its flight, after not properly transitioning into ‘flight mode’ – a transition that is required for take-off.
NASA announced at the time that it was previously aware of a technical glitch that results in a 15 per cent chance per take-off that Ingenuity would not transition into flight mode. However, NASA’s JPL assured the public that the helicopter remained in good condition.
Then, just days after its false start, the Mars Helicopter successfully completed its fourth flight test, and again performed exactly as planned. On this test, Ingenuity flew south approximately 133 metres, and then back to its original take-off position, for a total return trip of 266 metres.
In total, the Mars Helicopter was in the air for 117 seconds, which made the fourth test the longest of Ingenuity’s ventures to date.
According to NASA’s JPL, Ingenuity was able to capture a slew of colour images during this fourth flight, as well as black-and-white photos captured by its navigation camera underneath the aircraft.
“During this flight, we saved even more images than we did on our previous flights: about 60 total during the last 50 metres before the helicopter returned to its landing site,” NASA revealed.
While capturing colour images provides a “technical challenge” for Ingenuity, these photos allow NASA to better study the surface and features of Mars from above.
The fourth test flight also resulted in our very first audio recording of an aircraft buzzing through Martian skies, recorded by Perserverance’s SuperCam microphone.
The rover was parked around 80 metres from Ingenuity’s take-off and landing spot, and mission control was unsure if the noise of the rotorcraft’s blades, which spin at 2,537 rpm, would be audible over the sounds of the Martian gusty atmosphere.
However, scientists were able to isolate the sound of Ingenuity, to better hear the hum of Ingenuity above the winds.
A black-and-white image captured by Ingenuity’s own navigation camera during its groundbreaking first flight.
A new frontier – the fifth flight and beyond
Ingenuity’s fifth flight was a rather special one indeed, as the rotorcraft performed its very first one-way trip, to a brand new and unexplored path of Martian soil.
On 7 May 2021, at 7:26pm UTC, Ingenuity took off from Wright Brothers Field, before it travelled 129 metres south, retracing its route from test flight four.
It soared to a new record height of 10 metres to scope out its new surroundings, and take additional photos of the area around and below it, before landing. The flight lasted a total of 108 seconds.
Ingenuity’s newest landing zone was chosen specifically by NASA based on information previously recorded from Ingenuity’s test flights. Through information provided by Ingenuity, NASA was able to generate digital elevation maps indicating almost completely flat terrain with almost no obstructions.
According to NASA, the fifth test flight marked the transition into Ingenuity’s new operations demonstration phase.
This next phase focuses on investigating what kind of capabilities rotorcraft operating from Mars can provide, such as scouting, aerial observations, access to areas inaccessible by a rover, and detailed stereo imaging from atmospheric altitudes.
“These operations and the lessons learned from them could significantly benefit future aerial exploration of Mars and other worlds,” NASA said.
As the Perseverance Rover carries Ingenuity’s communications base station, it’s important the two stay nearby, however, Ingenuity will now be travelling ahead of Perseverance, though keeping in the same direction.
“The plan forward is to fly Ingenuity in a manner that does not reduce the pace of Perseverance science operations,” said Bob Balaram, chief engineer for the Ingenuity program.
“We have already been able to gather all the flight performance data that we originally came here to collect. Now, this new operations demo gives us an opportunity to further expand our knowledge of flying machines on other planets.
“We bid adieu to our first Martian home, Wright Brothers Field, with grateful thanks for the support it provided to the historic first flights of a planetary rotorcraft.”
Following a minor anomaly during its sixth flight attempt, Ingenuity also performed its seventh and eighth test flights perfectly.
The space agency has held back from releasing as much information surrounding its latest tests of the Mars Helicopter as it did previously, likely as the rotorcraft has largely completed its sole function – to prove that humans can engineer flight on a foreign planet.
For now, NASA will continue to see Ingenuity fly to new landing zones, and keep it within range of Perseverance.
An eventual end for Ingenuity
It appears likely that Ingenuity’s creators were not expecting the strong-willed rotorcraft to continue to function past its fifth test flight, and had limited concrete plans for the aircraft following those flights.
In fact, since as early as its third flight, it was confirmed that Ingenuity’s career may be short-lived, at least according to Aung, the helicopter’s project manager at JPL.
NASA confirmed that it intends to push the rotorcraft to its upper physical limits, testing the extent of its speed, height and range limits.
“We will be pushing the envelope,” Aung said. “And, ultimately, we expect the helicopter will meet its limits.”
You see, Ingenuity was never sent to Mars as a new means of space exploration, but was instead seen as a demonstrator model for future iterations, that would be seen as formal explorers, like the Mars rovers.
So, now that Ingenuity has “met or surpassed all of its technical objectives”, according to NASA, the JPL team will simply continue to test the upper extent of Ingenuity’s abilities until the rotorcraft’s inevitable demise.
Ingenuity successfully met all of its set objectives as early as its third test flight, when its top speed exceeded that achieved in test conditions on Earth.
“From millions of miles away, Ingenuity checked all the technical boxes we had at NASA about the possibility of powered, controlled flight at the Red Planet,” said Lori Glaze, director of NASA’s Planetary Science Division.
“Future Mars exploration missions can now confidently consider the added capability an aerial exploration may bring to a science mission.”
