The legacy of 'Ingenuity,' NASA's helicopter on Mars

Last month, the Ingenuity ended its mission as the first aircraft to make an extraterrestrial flight.

After nearly three years on Mars, what did it teach us?

Today, On Point: The legacy of 'Ingenuity,' NASA's helicopter on Mars.

Teddy Tzanetos, project manager of NASA's Jet Propulsion Laboratory's Ingenuity Mars helicopter

Havard Grip, chief pilot of the Ingenuity. He led the development of its aerodynamics and flight control system.

MiMi Aung, director of technical program management for Amazon's Project Kuiper. Former project manager of the Ingenuity.

Part I

MEGHNA CHAKRABARTI: MiMi Aung couldn’t fall asleep.

MIMI AUNG: I probably tried to go to bed. I can’t remember what time I went to bed. It might have been close to 9.

CHAKRABARTI: And for all MiMi cared, the dark space between her and her bedroom clock might as well have been just as far as where her mind was actually whirring … 140 million miles away.

AUNG: I have to share with you. I don’t know if I’ve shared publicly like this. I actually got quite emotional the night before when I got to prepare for the portion of if it didn’t land properly.

CHAKRABARTI: “It” was a tiny vehicle, less than 4 pounds, and the where was on Mars.

AUNG: This is the first time it left our planet, right? So, yeah, definitely, it’s a first of a kind mission. There’s no manual prewritten. My name is MiMi Aung. I’m the former project manager for Ingenuity Mars helicopter.

CHAKRABARTI: Time ticked by slowly.

AUNG: I got quite emotional because I ended up walking through all our journey and what each success was. When we did our first proof of concept flight to when we really achieved the mass, and then we were put onto the rover, which was like incredible, right? Like our dream come true. Like, we were going to Mars, right? And then now we're at Mars and doing that and how proud we were.

CHAKRABARTI: But the team still didn’t know if the little ‘copter could actually fly on Mars. This is On Point. I’m Meghna Chakrabarti. The night of April 18, 2021 edged toward the first minute of April 19, when suddenly, MiMi's phone lit up.

AUNG:  And I think I remember around midnight, Bob Balaram texted me.

CHAKRABARTI: MiMi was the head of NASA’s Ingenuity team. Balaram was the team’s Chief Engineer.

AUNG: And I said, “Hey, Ingenuity should have flown by now.” And because there was a time lapse and now it was a few hours later that the telemetry was going to come back down. But around that time he texted me. He's like, “Yep, it should have flown by now.” And I remember that text.

And then of course, then you drive in the dark, and you get there, you're seeing people you haven't seen for a long time. It was really exciting. We were extremely conservative about COVID, so we hadn't seen each other. And in fact, it was the first time a lot of us had been back in the same room. So there was a lot of emotion charged there. But I still — after all the excitement then, I think there was, it was very somber. It was pretty much like thinking and just kind of pacing, not so anxiously at that point, but still pacing and thinking about all the outcomes.

And then, the time came when the telemetry was going to come down.

CONTROL ROOM 1: This is downlink. Data products are prepared to be in. We will begin processing shortly.

AUNG: And then I think I was, uh, Garrick next to me. I started moving around like a little bit and he started to see some telemetry and I'm like, you know, trying to read his body language and everything.

CONTROL ROOM 1: This is downlink, we have pulled in data products from Mars 2020. Confirming that we have helicopter data products, helicopter telemetry, helicopter events.

CONTROL ROOM 2: Rotor motors appear healthy, swatch plate servos appear healthy, overall actuators appear healthy.

FLIGHT CONTROL: This flight control confirming that we have EVRs from Ingenuity. Ingenuity’s reporting having performed spin up, take off, climb, hover, descent, landing, touchdown and spin down.

AUNG: And then for me, the most exciting moment where I allowed myself to accept it, more than the video of the first flight that came down from Perseverance's camera, when I saw the altimeter plot.

FLIGHT CONTROL: Altimeter data confirms that Ingenuity has performed its first flight, (shouts, applause) the first flight of a powered aircraft on another planet.

AUNG: Because you knew right when it was supposed to go up, you knew what the altitude should be, you know what the duration, and then you're looking at the jiggles like, oh, it's a really smooth glide. And then came back down perfectly. And I think that's when I say I can jump, I can actually celebrate.

That’s it, yeah. (LAUGHS) That’s where the geeky side comes out. I had to see that plot. I can’t celebrate on just, it went up and it’s flying, yeah. (LAUGHS).

AUNG IN MISSION CONTROL: We can now say that human beings have flown a rotorcraft on another planet. (CHEER)

AUNG: Another thing that I haven’t really spoken about. The adrenaline rush, it’s really intense. So I remember after all the excitement, the room was empty, walking from one building to the other, I got really sick. And somebody says, “Oh, it’s the adrenaline crash.”

It was an intense journey, right? Because every time, if we didn't demonstrate lift, we probably wouldn't have gone to the next step. If we didn't fly it, people might have said, well, another time. Right? So every step, our team, we wouldn't allow ourselves to celebrate. And especially, Bob and I were not as bad, but like Havard Grip and Teddy Tzanetos and a lot of the team members, these are like, Let's not, we're not going to celebrate until the real thing, right? So it really was the first, I think it was feeling permission, like to actually celebrate.

That teaming, the extraordinary, high engineering, highly technical. Thinking together and working our way out of several places that we were stumped on and the bond that we formed. I have to say, that's, when I think back, it reinforces my belief that you can make really difficult things happen. And we did that. Our team was really connected that way because we never had to filter ourselves, because it was so hard to do that we had the freedom. So I really, truly believe in teamwork, and hard work and being very technical and objective to make things happen.

I’ve said before that the sky is not the limit, meaning really, you can really get things done.
And I look at Ingenuity and the fact that now we don't have to wonder if it is possible to have missions that fly at Mars and to start using the aerial dimension for space exploration. That is a great thing to add to the arsenal of deep space exploration. But I think I look at this mission more personally. For me, it was ultimate reward to be in such a crazy team going for crazy thing. But being really razor focused together. It doesn't come all the time. These are like magical team experience and that's what I remember the most. And then Ingenuity rewarded us all like with just this unexpected, like beyond our wildest dream, performance.

CHAKRABARTI: MiMi Aung. She was the project manager of NASA’s Ingenuity Mars helicopter. Now beginning in April 19th, 2021, from that first success, Ingenuity's original mission was supposed to be a mere five flights, total little hops to prove powered flight was possible on Mars. The copter ended up making 72 flights.

The mission was intended to be just one month long, but Ingenuity kept going for almost three years, covering more than 11 miles of the Martian surface. But on January 18th of this year on its 72nd flight, Ingenuity damaged at least one rotor blade on touchdown. And NASA ended the copter's mission a short while later, but not without making this thrilling observation.

Lori Glaze, director of NASA's Planetary Sciences division, said quote, "Ingenuity absolutely shattered our paradigm of exploration." Or, as you heard MiMi Aung put it a little bit earlier, humanity can still make difficult things happen. So what can the rest of us learn from the little copter that could?

Joining us now is Teddy Tzanetos. He served as the project manager for Ingenuity by the end of its mission. Teddy, welcome to On Point.

TEDDY TZANETOS: Hello Meghna. Thank you for having me.

CHAKRABARTI: And also with us today is Havard Grip. He served as the chief pilot of Ingenuity and led the development of its aerodynamics and flight control system.

Havard, welcome to you as well.

HAVARD GRIP: Hi. Thank you so much for having me.

CHAKRABARTI: And first of all, let me just congratulate both of you and everybody that has been involved with the Ingenuity Project. It really is an almost unimaginably awesome milestone in human exploration. So I just wanted to say that first and foremost. But Teddy, how are you feeling now?

It must be more than a little bit bittersweet that Ingenuity has finally so many years later ended its mission.

TZANETOS: Yes. I would say for the first 24 hours after we made the determination, we've finally reached the end. It was a little bittersweet. But since then we're on the Martian equivalent of cloud nine.

It's really been a wonderful last couple of days. The team is still in communication with Ingenuity. She's still alive. We have this expression within the team, WENDY, which stands for We're not dead yet. And we've had a great time collecting as much information as we can to try and piece together exactly what happened in that last flight.

But it's also provided the team with an opportunity to get some perspective and really appreciate how lucky we've all been to be a part of Ingenuity and what a marvelous journey this little aircraft has actually had.

CHAKRABARTI: Yeah, I think, was it just yesterday that NASA released some pictures of where Ingenuity is right now, resting on a Martian dune somewhere?

TZANETOS: Correct. We got some imagery from the Perseverance Rover. Our team works very closely with the rover team. And we've been planning, as soon as the rover got around a hill, to take the best image we can from an advantage point of Ingenuity's resting spot and area, our internal helicopter teams calling Valinor Hills.

CHAKRABARTI: Okay, now Havard. You're of course the person who flew Ingenuity around as the chief pilot. We'll talk a little bit later about how exactly that happens. But same question to you. Is it bittersweet? Does it almost, do I dare ask if it almost feels like losing a member of your family after being so intimately involved with the project for so long?

GRIP: For me I have to say it's mostly sweet yeah, a little bit bitter. But the mission had to end one way or another, and in a way, I think it ended the way it should have. With Ingenuity still pushing the limits. That's how it went out and that's how it should have gone out.

And I look back at this as just a huge success. And in terms of losing a member of your family, For me, I admit, I don't attach the personality to Ingenuity. To me it's more about the team, the team that built Ingenuity. That's what I look back on, the experiences that we've had together, being in the trenches together and making this happen.

That's what I look back at, that, a little bit of sentimentality.

CHAKRABARTI: Yeah. You know what, Havard, I really appreciate what you're saying. Because I think right now there's lesson No. 1 about what we can learn about how to do big things. Don't romanticize the project, it's the people that you care about. And then don't romanticize the actual work. Because it's going to be hard, but it's worth it.

Part II

CHAKRABARTI: So here's the thing that I want to spend a few minutes talking with both of you about and really learning deeply. Because it's not just the imagery that Ingenuity sent back, which is remarkable, or the fact that it flew, but how this little copter was actually constructed because I didn't know until recently.

And Teddy, I'll start with you here. It couldn't be that heavy obviously, because it was positioned underneath the Perseverance Rover and there's always weight limitations on getting things to space. But NASA, the engineers used off-the-shelf components to build a Mars helicopter. Is that right Teddy?

TZANETOS: Correct. The fact that Ingenuity happened at all was really a confluence of a bunch of different things in the industry. Not just the fact that we had a one-of-a-kind team, an opportunity to launch to Mars with the Perseverance Rover, Mars 2020. But a lot of it had to do with the technology of today.

And when I say today, really, I mean of 2013, 2014. Ingenuity is powered by a cell phone chip. And that wouldn't have been possible back in the nineties when our chief engineer, Bob Balaram, originally started thinking about the idea he sketched out the mathematics. It all made sense.

But if you remember back in the '90s, cell phones were bigger than bricks.

CHAKRABARTI: Yeah.

TZANETOS: So you could not fly that '90s technology and still make an aircraft lightweight enough to fly at Mars. So when the opportunity presented itself, 2013, 20 14 to 2015, we were able to take cell phone chips, lithium-ion battery technology, which is extremely energy dense, extremely power dense, as well.

And you can actually construct an aircraft that stands a chance at actually flying on Mars, which has, I remind everyone. 1% the density of Earth's atmosphere at sea level. So there's almost nothing, right? So you need all those bits to come together at the right time, and then you might stand a chance at actually flying to Mars.

CHAKRABARTI: Okay, I've grown old enough that few things are literally jaw-dropping to me anymore, but this is one of them, right? That I'm seeing here. It's a Qualcomm processor.

TZANETOS: Yes.

CHAKRABARTI: From roughly 2015, weighs half an ounce.

TZANETOS: Yep.

CHAKRABARTI: One can only imagine how many more orders of magnitude powerful current cell phone chips are.

And you were able to also, you said the batteries, they were off the shelf not developed specifically for NASA batteries that were able to withstand the insane temperature changes.

TZANETOS: Yep. Absolutely.

CHAKRABARTI: And launch, and all the difficult environmental factors on Mars.

TZANETOS: So correct. And there's two reasons for that. Not only were off-the-shelf lithium batteries extremely high performance. We were effectively riding the wave of advancements from the industry for free. But the other aspect to that is the fact that Ingenuity was a tech demonstration. What a tech demo is for NASA is a high-risk, high-reward, low-budget mission.

If it works, great. If it doesn't, it's okay. It doesn't have a core science objective. And that last part, the low budget means that you couldn't go and invent a brand-new battery purpose-built from Mars. You couldn't go and get a lightweight radiation-hardened processor from Mars. You are forced to use whatever you can get, right?

So a vast majority of Ingenuity, we just went online and bought parts and made some good engineering judgments about what we thought would work. And then we also built the airframe with our partners at our environment. All the carbon fiber, everything from the outside, that is of course custom.

But what we're talking about are the electronics, the internals. A lot of that you could find in any university electronics lab around the country.

CHAKRABARTI: Oh my gosh. Okay, so on behalf of all mobile phone users out there, I'm going to ask right now if a cell phone battery, or sorry, a lithium battery can survive on Mars, why does my iPhone always go on strike when it gets too hot or too cold here on Earth?

But maybe that's a question I'll turn to Apple here, but your point about being able to use off-the-shelf components to achieve such a remarkable mission is incredible. Havard, let me turn to you. Tell me how that design philosophy went into the flight control systems for Ingenuity?

GRIP: The off-the-shelf philosophy is also enabling for the flight controls, because this type of vehicle, it's not like vehicles that you're used to operating. In your daily life, it's not like your car. In particular because a helicopter, it tends to be unstable. It doesn't want to stay right side up.

It just wants to turn over and crash if you take your hands off the steering wheel, so to speak, so it requires a computer to stay on the ball constantly. And constantly make minute adjustments to the controls just to stay right side up. So 500 times per second you make minor controls, and controls adjustments.

And even faster than that, we measure the motions of the vehicle using what's called inertial measurement unit, measures accelerations and angular rates. 3,200% second, we make those measurements. And 30 times per second we take images of the ground and analyze those images for features, how they move across the field of view so that we can understand how the helicopter works.

And being able to do that at such a rapid clip is just not something that's possible with the kind of hardware that you normally deploy for planetary exploration, this is only possible by aggressively leveraging commercial off-the-shelf technology. That's been developed for cell phones or for drone technology in the commercial market.

CHAKRABARTI: Okay so then in terms of its actual physical requirements for achieving flight, as Teddy mentioned, the Martian atmosphere is 1% as dense as sea level earth atmosphere. And I think, I guess the earth-based equivalent would be trying to fly a helicopter at 80,000 feet, which is just not possible.

I was reading that most helicopters or even the specialty helicopters won't go above or even near 25,000 feet, which is why, let's say, Mount Everest rescues are very hard above a certain altitude. So what were the rotor blades made of Havard? And just tell me like how, what kind of thinking needed to go into actually just figuring out how do you get something to fly in 1% dense atmosphere.

GRIP: Yeah, so the obvious thing, when you say 1%, you think it's difficult to produce enough thrust, and that is obviously true, and that was true from the start. But at the beginning, we were maybe a little bit naive about things. Because that's the kind of the only thing we focused on upfront.

We thought this is all about making the vehicle very light. And we have to have a large enough rotor, spin it fast enough, we produce enough thrust. And that's true, but it's only part of the answer. What we discovered when we started trying to demonstrate the viability of this is that besides the lack of thrust in this atmosphere, it also changes in a fundamental way how the vehicle handles, like it handles in a totally different way. Imagine that you're driving your car, but your steering wheel is attached to your front wheels via bungee cords. That's what it's like. If you try to build a helicopter for Mars, the way you might build one for Earth.

And that was a lesson that we had to learn. And it really kicked off an intensive effort to understand just the fundamentals of how vehicle handles on Mars. And you mentioned the rotor blades. That's one, that was one of the solutions to that problem. The rotor blades on Ingenuity, they're a work of art.

They look substantial, when you look at them, but if you try to lift one, it's light as a feather. Even I, when I lift ones, I still get surprised every time, just by how light it feels and having them be that light and simultaneously extremely stiff. That was one part of the solution to the handling challenges that we found with trying to fly in this thin atmosphere.

CHAKRABARTI: And the whole weight of Ingenuity was about four pounds.

GRIP: That's right.

CHAKRABARTI: Four or five cans of soup at the maximum, just to get a sense as to how light it was. And when you talk about handling, it's not like you're getting real time responsiveness, because you had to wait hours and hours for the flight commands to be sent to Ingenuity. And then for Ingenuity to do its mission and then to send the results back. So I want to talk to you about that a little bit later, about how adjustments are made when there's that much delay.

But Teddy, in the spirit of what can we learn. From all that Ingenuity has taught not just NASA or scientists or engineers, what do you think the big lesson is for just people listening right now, when you say that you used off-the-shelf components for a path-breaking planetary helicopter.

TZANETOS: I see what this team has accomplished here, right? As a huge marker in the ground. For all future Aircraft development, spacecraft development. Not just for Mars, the other outer planets, deep space in general. This is a huge victory to show all of humanity that yes, we can build things in a different way, right?

We don't need to do. Everything to the 9.99999% certainty, right? We can rely on more affordable technologies, and the way in which we develop those spacecrafts, that is a really a golden nugget of value that we've forged the path for here with Ingenuity. That allowed us to do --

CHAKRABARTI:  Can I just jump in for a second, Teddy, and I'm sorry. I'll let you finish your thought in a second but, so you mentioned, excuse me, it's either Bob Balaram, that it was originally his idea to look for off-the-shelf components. Is that right? Did I hear that correctly?

TZANETOS: Yeah, and it was a team effort.

CHAKRABARTI: Team effort. Okay.

TZANETOS: But yeah.

CHAKRABARTI: Yeah. The reason why I ask is because that moment seems to be very important, not just obviously from him, but from the team, that there was even this thought like, oh, maybe we can't do this using components specifically made for NASA. Let's look elsewhere. What is it about the team that opened the door to that kind of thinking?

TZANETOS: The willingness to take some risks is really what it boils down to, right? And not being scared to take those risks, not being scared to fail, pivot, fix it, pivot, fix it. And eventually, you trust the system there. You trust that the team's going to make it through. We're here now after two and a half years successful mission.

There were a lot of small changes and small adjustments along the way during the development process where we tried things and they didn't work, we didn't have a manual to work from. No one had built a helicopter from Mars before. No one had tried using a cell phone chip before. We were writing the book along the way.

So they were small and big engineering gambles. Some of them paid off, some of them did not. And eventually we got a design that worked.

CHAKRABARTI: Wow. I 100% predict that someone listening to this show right now, or at least I'm hoping, a young person listening to this show is going to go and buy a cell phone chip and some other off the shelf parts and see what they can do.

TZANETOS: (LAUGHS) I hope so.

CHAKRABARTI: Even here on Earth. But I had, sorry, I had interrupted you because you were saying that this has a powerful impact on future missions, maybe missions even in development right now in terms of components that you can use and what you can hope to achieve. So tell me more about that.

TZANETOS: Yes. Yes. So NASA is working on another aircraft, the Dragonfly mission to Titan. And there are ways in which we're feeding lessons forward to that team and to that mission. But just to give the listeners at home here a sense of the magnitude, the processor onboard Ingenuity and all of the processors combined.

It is more than a hundred times more powerful than everything we have sent out into deep space combined, right? So when you take the Perseverance Rover, the Curiosity Rover, Insight, the Voyagers, for the Star Trek fans out there, V'ger, right? All of those missions, you combine all the computing power together.

And Ingenuity is still a hundred times more powerful than that, right? That unlocks a lot of potential, not just in terms of what U.S. aircraft nerds, like focusing on which is the aircraft performance and how fast we can fly. How high we can fly. But also for the scientists, right? And for other engineers that have interesting use cases.

You can now use that resource out on another planet to do something that you maybe aren't thinking about today, but you may in the future. That's really enabling, I believe, for future missions.

CHAKRABARTI: Wow. You had to throw that star Trek reference in there, Teddy. I'm trying so hard not to drag this conversation into references to like Carbon unit Chakrabarti.

TZANETOS: (LAUGHS)

CHAKRABARTI: I'll leave it at that. So Havard then, similar question for you, in terms of the process that goes into designing, flight control systems, et cetera, how do you see what you were able to, the team was able to achieve with Ingenuity? Influencing future missions?

GRIP: Yeah, I think it has a potential to have a huge impact. Because we demonstrated, we demonstrated some technologies that proved to be extremely successful and an approach to developing those that is atypical.

And as Teddy has mentioned, the use of commercial off-the-shelf components, as part of that. And then being able to leverage that to implement algorithms the way we did, that really made use of that, and I'm talking in particular here, the visual inertial navigation system. That was able to use those images at such a rapid clip, like I said, 30 times per second, analyzing images and navigating using that.

And seeing how successful that was. Yeah, I can't think that is going to have an impact, a feed-forward impact on future missions.

CHAKRABARTI: It seems that it's going to definitely also have an impact on private space exploration, right? If you can be so successful with off-the-shelf components, does that – Havard, let me stick with you.

Do you think that opens the door even more to non-NASA missions?

GRIP: I would like to think that the entire community that is engaged in space exploration, will look at this and take inspiration from it, for sure.

CHAKRABARTI: And Teddy, what do you think about that?

TZANETOS: Absolutely. I agree with Havard.

We've shown it's possible, right? The evidence is there. Clear as day, there's 72 flights worth of data to back it up. And I encourage anyone who's got an idea out in space to look at what the team has done here. Look at the designs and take what you can use and improve upon it.

CHAKRABARTI: We've just got about 30 seconds before we have to take our next break here. Teddy, I mean, I want to talk more about what Ingenuity helped us discover about Mars itself, but if there's a, do you have a favorite image that the copter sent back?

TZANETOS: My favorite image would probably be from Flight 13, Faillefeu.

There's an outcrop called Faillefeu and the scientists from the 2020 mission were interested to see for the first time in our mission since we went into extended operations, could we go out and scout. And we generated this beautiful 3D image compositing multiple high-res shots.

And it's really a perfect example of what you can do with that new aerial dimension in Mars.

Part III

CHAKRABARTI: Havard, let me start with you. How, tell me a little bit about, so your dreams as a kid and the path that led you to being part of a team that was the first to fly a helicopter on another planet.

GRIP: Yeah. Looking back at when I was a kid, pretty much what I knew was I wanted to do something with computers. That was really, it was pretty ill-defined, I would say. But it's also, what I ended up doing in some ways I studied something called Engineering Cybernetics which is a fancy word for control theory.

It's about writing algorithms to control different types of systems. I used that knowledge to work a little bit for the automotive industry. I spent a lot of time writing theorems and proofs, academic papers. And then eventually I ended up at JPL and early on in my JPL career in the first year, this Ingenuity project got started.

Bob Balaram, who is our chief engineer, he recruited me to lead the flight controls and aerodynamics portion of it. Which is crazy in a way because I had no real background with helicopters. Hadn't really done anything with space even up to that point. But Bob thought this was a good bet and I thank him for it.

It was an incredible opportunity. And that's how I got started. And I just started reading and learning and experimenting. And here we are, we're 11 years out and I can look back and this is what's been defining for my career.

CHAKRABARTI: Wow. So Bob saw something in you that he was very confident, was worth taking a chance on. And so glad he did it. Teddy same question to you. What was your path that led you to being part of the Ingenuity team?

TZANETOS: So the start of my nerdy journey, we're all a little bit nerds on this team, right?

CHAKRABARTI: No, you're kidding.

TZANETOS: But it really goes back to when I was a little kid. My father he had a business, he was making industrial sewing machines.

In New York, and I remember when I was a little kid, I was playing in the backyard with pneumatics, electronics, and I really wanted to understand how do these systems work? How do the mechanisms work? How does a computer do its thing? Back then, I just knew how to play Minesweeper. But that's when I got bit by the bug, so to speak, and really got that hunger inside of me to understand and disassemble things and put 'em back together.

Went to school for engineering, computer science, electrical engineering. Worked for some research labs, DOD work. Started getting involved in drone work and it was one Christmas I went home in New York, went to a hobby shop and I bought myself my first helicopter, and I went to the hobby shop, and he is like, you know how to fly this thing, right?

I'm like yeah. He's like, "It's not for beginners." I'm like, "Yeah, no, that's fine." And I blew it up in my backyard and I knew I was hooked. I was like, "Okay, I love this. Helicopters are amazing." And eventually I was lucky enough to get a job at NASA JPL. And when I first joined, I wasn't on the helicopter team.

By then MiMi, Bob and Havard were about to start the engineering phase, engineering model phase. And I begged my boss at the time, please introduce me to anyone on the heli team. I'd love to join up. And similar to Havard's story, Bob gave me a shot. I met Bob and I said, whatever you need.

I'm happy to do it. He said, there's some cables in a closet. We need someone to make some electrical ground support equipment, which you can think of as life support. It's a piece of equipment that's life support for your spacecraft. And things snowballed from there. Took on test conducting roles.

We have what's called assembly test launch operations, Delivery to Kennedy Space Center operations and now here at the end of the mission leading the team. And it's been a remarkable journey, and we all are incredibly grateful to have had that shot, to be any small part of it has been remarkable.

So we have to thank that that RC helicopter that you first.

TZANETOS:  Exactly.

CHAKRABARTI: Yeah. I'm sure it blowing up was actually probably helped, but in terms of how cool is that? But there's this thirst to experiment and to try and a high-risk tolerance that I'm hearing in both of your stories here, which obviously comes in very handy when you're doing something that no one has ever done before. Teddy, like you said, there was no handbook for how to fly a helicopter on Mars. So obviously there's probably countless challenges that the team faced, not just in the design and testing phase, but of course while doing the 72 flights on Mars.

So Havard, let me ask you, were there times when, or when those challenges popped up, how did the team go about solving them, especially when there was so much at stake when the copter was actually on the Martian surface.

GRIP: I think what distinguishes this team is that it's always extremely technical.

We don't, screw around. We just get down to the nuts and balls and the technical details and also that's how the team reacted when those issues came up. There's inevitably going to be curve walls that Mars throws at you. And we just went into the sort of technical mindset of figuring it out, staring at events from the helicopter, staring at telemetry, trying to piece together the little scraps of information that we had in order to understand what went on. And that's been the case all along and we had multiple challenges that we've worked through. And it's the case now that the mission has ended, but we're still talking to the helicopter and we're still picking up little clues about what happened during our last flight on Mars.

CHAKRABARTI: Teddy, give us a specific example. Because I think it was Flight 52, that there was some communications problems. Is that a good example of the unexpected that happened and how the team solved it?

TZANETOS: Yeah, we've had plenty of curveballs here on the ground before launch and in operations on Mars.

I think Sol 426 and around when you're talking about. Is when we first ran into winter on Mars. We designed Ingenuity to be a spring chicken, right? Survive 30 SOLs. That's it, in a warm spring environment. When we made it to our first winter, which was never, it was never designed to do, we knew that the energy balance was gonna go in a trend that wasn't gonna work out great for us.

And eventually we got to the point where we lost contact with the baby. We woke up here on Earth. And went into work and we said, all right, what data do we have today? And there was none. And that's an example of really when the team put on its game face. We got into a small, ten-by-ten conference room where we can all look each other in the eyes and try and piece together, from physics first principles, that is a huge tenet here. Of start with the physics and work your way from there in terms of understanding what happened. And that's what we did. We looked at the solar installation, how much energy was coming from the Sun's rays, models and predictions of the environment.

How windy was it the night before? How cold was it the night before? And using those bits of information. And the math behind it, we were able to come up with a theory, and then we made a test to see if the theory was correct. We uplinked that to the surface of Mars and over the course of two days, we were able to what we call, recapture the helicopter and communicate reset clocks.

Reset alarm clocks, and that's why we were able to continue the mission for as long as we did. So that physics first principles is a huge part of everything that the team embodies, but especially in those curveball moments it's important to keep your wits about you and keep the emotions down.

And just focus on what you know and keep in mind what you don't know.

CHAKRABARTI: Yeah. So you kept referring to Sols, as in earth days, right? Because the Martian year is so much longer than an earth year. But that brings to mind, and Havard, and I had meant to ask you this earlier, about the fact that you are communicating with a helicopter that's a hundred plus, 140-ish million miles away, and the time to get to commands to Ingenuity and back. That round trip is like, what, six-ish hours? Is that right?

GRIP: It varies depending on how Earth and Mars are positioned.

CHAKRABARTI: Their relative position. Yeah.

GRIP: But it's always, it's always, yeah.

Yeah. It's and when we talk about hours here, we are really talking about the time that it takes not just for the lights or the radio signals to travel between Earth and Mars. But also, the time that it takes to relay that information through multiple points.

CHAKRABARTI: Okay. So that means that there are many hours of essentially no communication, right?

There's just like a huge period of time where, of uncertainty, tell us about like how the team figured out okay, what kind of flight do we want to ask Ingenuity to do? And then I just presume that those commands are sent to the copter. But how did you decide in advance what you wanted the copter to do?

GRIP: Yeah. So when it comes to controlling a helicopter on Mars, I think of it as a two-stage process. One is you got to write algorithms that lives on board the helicopter, that gives the helicopter the ability to make those minor adjustments during flight, thousands and thousands of them. And that allows it to stay upright during a flight.

So those are algorithms that live on board the helicopter and makes all of those tiny little decisions in real time. But then the big decisions about flying, those we research for us on Earth that are operating a helicopter. And so we look at maps, we look at the weather, we look at the terrain in the area.

We make those decisions about, where is it safe for the helicopter to fly? And part of that process is also experimenting with it on earth. And when I say experimenting here, I'm talking about using simulations. So we have some fairly sophisticated computer simulations that we built up for Ingenuity that we use to try out things on earth before we uplink it to Ingenuity.

But at the end of that process, we upload a sequence that tells Ingenuity exactly what to do, down to every single maneuver that it's going to do. It's going to spin up to the rotors to a certain speed, it's going to take off, it's going to accelerate a certain rate, climb to a certain altitude, and so on.

All of those decisions are made here, but then it's up to Ingenuity to execute that and tell us afterwards how it went.

CHAKRABARTI: Huh. We've only got a few minutes left, unfortunately, in this conversation, and I want to end with this again in the spirit of what can we all learn. Because I don't know. I think Ingenuity's success has come at a very good time for this country and for people as a whole. Because you look left and you look right and groups not being able to work together to get big things done. Obviously, I'm thinking of politically most obviously. But in Ars Technica their senior space editor, Eric Berger, recently wrote a story and Teddy you actually quoted in it.

But here's how he ends his story. He says, this is Eric's writing, he said, I have naturally become a little jaded over time as I've watched NASA and other space agencies around the world take two steps forward and one step back. Space is hard. Battling through bureaucracy is hard. There's a lot of BS out there in the space industry, he said.

But then he says, but the launch, deployment and astonishing performance of Ingenuity during the last three years has truly taken my breath away. It is a phenomenal engineering achievement and a real triumph of the engineers over some NASA management who never wanted Ingenuity to fly. As Americans, as humans, we can all be proud to witness flight on another world.

So Teddy, do you think the kind of accomplishment over bureaucracy, and there's always politics in bureaucracy, do you feel hopeful that that can happen outside the context of a Mars helicopter?

TZANETOS: I do. And I feel like I would expand it beyond just, there's always going to be bureaucracy.

But even within teams and outside of teams, really trying to break free from molds, and to be okay with some discomfort about what did the previous generation do? And why? Understanding why and being okay with taking some risks and changing it. That was a big part of changing the mentality of our own team, right?

Because there's never been an example of how do you fly a helicopter on another planet? How do you build a helicopter for another planet? How do you even test a helicopter for another planet? We had to break a lot of rules and we call them flight project practices and design principles. The DPs are not written yet for the next helicopter.

And we're working on that. (LAUGHS) But that's part of getting through not just political bureaucracy, but organizational bureaucracy, and do not take rules for granted. Always challenge and understand, again, back to the physics, why were they written in the first place, and do you agree with them?

And if you don't, be willing to fight.