• What just happened to Bonza? Why new budget airlines always struggle in Australia
• Flying high! UNSW engineers help make David Unaipon’s ‘helicopter’ dream a reality
• Privatising the sky: drone delivery promises comfort and speed, but at a cost to workers and communities
• From ‘open skies' to 'slot-hoarding': the turbulent world of aviation laws explained
• Flying cars could soon be ready for take off

Voiceover | 00:06

Welcome to UNSW's Engineering the Future podcast, a series where we'll speak to academics and industry leaders who are embracing cutting edge ideas and pushing the boundaries of what is truly possible. In this episode, we'll take a deep dive into the developments in the aviation industry, and discuss what impacts we can expect on society as a whole over the next two decades. We'll hear from leading experts in the field, Dr. Sonya Brown, and Andrew Moore, about the emerging technologies in hydrogen and batteries that will help lower emissions from the aviation industry. They will also look up to the skies to discuss the feasibility of flying cars as the preferred way to commute, or whether more passenger flights will be travelling at supersonic speeds. So join us as we discover how world-changing action starts with fearless thinking in Engineering the Future of Aviation.

Neil Martin | 01:05

Hello, and welcome to Engineering the Future of Aviation. My name is Neil Martin, and I'm a journalist and STEMM communicator working in the Faculty of Engineering at UNSW. Joining me today to discuss what changes we can expect in aviation and aeronautics over the next 30 years is Dr. Sonya Brown, a senior lecturer in aerospace design at UNSW Sydney. Sonya's research interests include multifunctional composite materials, structural energy storage capability, the continued advancement of high-quality carbon composite materials, and the development of technologies to reliably produce composite components for the aerospace industry. Welcome, Sonya.

Sonya Brown | 01:52

Thanks Neil.

Neil Martin | 01:53

Also with us is Andrew Moore, the founder of AMSL Aero, which is a sustainable aircraft design and manufacturing startup. Andrew previously served in the Royal Australian Navy as an Engineering Officer, performing foreign country peacekeeping missions, and managing fleets of helicopters. He has also held a range of senior engineering and business development leadership roles in the defence and commercial aviation sectors, including the design and build of aeromedical fitouts. Welcome, Andrew.

Andrew Moore | 02:28

Lovely to be here, Neil.

Neil Martin | 02:29

I'm excited to speak to you both about the future of aviation with so many interesting potential developments over the next 30 years. Whether that's finally realising the science-fiction dream of flying cars, or fueling passenger planes with hydrogen to significantly reduce the carbon footprint of air travel. But maybe to get straight into the discussion, I'll ask a big question that I think many people who fly long distances want to know. And that is, how fast do you think planes will be flying in 2050. And I say that as someone who once travelled supersonic on Concorde.

Sonya Brown | 03:06

I'll consider you very lucky to have travelled on the Concorde. But I do believe that supersonic travel is in our future. So we do expect to be doing you know, around Mach Two again over oceans, and that's very critical right, over the Pacific Ocean, or the Atlantic Ocean, or maybe the Indian Ocean. Unfortunately, we can't really do supersonic travel over land because there's, you know, too much impact to everybody else on the ground. Basically, those sonic booms aren't really something that people will accept. So yeah, I envisage that we will be travelling, like you maybe were in the past on the Concorde, into the future, once again...I really hope definitely by 2050, but hopefully sooner.

Neil Martin | 03:53

Are you slightly surprised that it's been since 2003 that that hasn't happened and kind of what needs to happen for it to be reintroduced?

Sonya Brown | 04:02

I think it's more of a business case thing. There's nothing technical stopping us from travelling Mach Two right now. There's nothing on the technical side, it's more about the business case. But there have been several aircraft in at least early development stages, particularly around the business jet side. For example, look at Taylor Swift recently, jetting around the world in a private business jet, who do have the kind of funds that that would require. So I think it will happen. It's just a matter of when that business case gets across the line.

Neil Martin | 04:34

Are you as confident, Andrew?

Andrew Moore | 04:35

Oh, look, I think, like many things, you know, there's a trade off. So flying faster, of course, uses a lot more energy as a consequence, uses a lot more fuel. And whilst there's a sustainability question mark over, you know, that higher performance flight. Now, as zero or low emissions fuels become widespread and cheaper than that, of course, opens up lots of things. So I know there are challenges around hydrogen-fueled supersonic air flight, not in the combustion of hydrogen, but just in the volume that hydrogen takes up. I think there's some great opportunities as we go to that real zero emissions. So essentially, all the guilt comes out of the travel as you go to 100% or near 100% renewables and that price of that hydrogen rapidly decreases and that price of zero emissions fuel decreases, then, I think you'll see, as Sonya says, a boom, if you pardon the pun.

Neil Martin | 04:35

But do you still think it will be quite a niche thing? I mean, Concorde was a niche aircraft. 100 seats only at that top level...business class fliers. Not the kind of thing that we're all going to be getting on in 2050.

Andrew Moore | 05:49

I think once again, it comes down to cost. And typically with those supersonic jets, you know, Concorde had so much airframe life left, because the flight times are so short, it didn't have corrosion problems, because the airframe got hot, which boiled off all the moisture, which meant it never corroded. So there's some interesting things around the other aspects of those aircraft, that if the fuel costs were low, then, you know, it would be a more viable form of transport for everybody else.

Neil Martin | 06:17

If there is a development of those supersonic planes. Does that also change the design? And also does that change the experience for the travellers? I'm thinking predominantly that we seem to be cramming more and more people into these planes, and do you think that that would only exacerbate the problem?

Sonya Brown | 06:37

So I think the Concorde as it is, although it was obviously expensive to travel on, it was much more of an economy business class for those reasons, right? Because to make it economical, back then, although obviously, it wasn't that economical, which is why we stopped, you really have to use that space wisely, because the-the aerodynamics at that speed is effectively different. And again, the fuel usage, as Andrew mentioned, is very, very different. So I think when we're ever looking for supersonic aircraft, that the space and the volume issue is-is definitely a critical one, you really do want to effectively get as many people in there as you can.

Andrew Moore | 07:23

The world of automation is flipping how technology is accessed and accessible. You know, if you look at it, the easiest aircraft to fly today has to be some of these hobby drones and camera drones that you see. You know, it takes you five minutes and out of the box, you're taking professional photography, and you know, flying like an expert. You know, there are companies that are doing auto-land for conventional aircraft with you know, their autopilots, those sorts of things. So you just push the button and it does everything. Obviously on big jets. It's been around for a long time, a little jets and little planes, it's now becoming commonplace. So I think there are alternative business models that we haven't thought about yet that will come to the fore over time. There's always going to be a place for large, high-volume aircraft. But there is a bit of a trend of smaller...so the A380 was too big, and you're seeing aircraft the size of the 737 being out competed by, you know, the smaller A220s and, you know, in the Embraer jet size so...so there's this interesting thing of more personalised travel, is where people want to travel in smaller groups. That's definite, you know, people aren't comfortable with somebody having a coughing fit in the front of the plane anymore. So yeah.

Neil Martin | 08:43

We might come back to that personalised travel in a little while but I wanted to stay on speed. You've mentioned there supersonic. I believe some people talk about hypersonic travel. I was reading...the Airbus had announced back in 2011, a zero-emission hypersonic transport potential plane. Hypersonic I believe travels at five times the speed of sound, which would have meant London to Sydney in a roundabout two to three hours. But as far as I'm aware, nothing much has happened since 2011. Does that mean that hypersonic travel is one of these kinds of very science fiction things that isn't really feasible, or is a PR exercise for some of these aircraft manufacturers? What do you think?

Sonya Brown | 09:36

So, I think there's a clear reason that nothing has really progressed on that and the progression, you know, for example, Airbus, instead is focusing on advertising their hydrogen development vehicles which travel at normal commercial aircraft speeds for the 2030s. And that's because for people it's not really that feasible to get to hypersonics. We've got really high G loads just to get there, more typically than a human can withstand. And the temperatures, the skin temperatures on the outside, we're talking like over 1000 degrees Celsius. So the amount of insulation you'd have to put there to make these vehicles to have humans inside just is also not particularly feasible. So I personally don't consider it very viable for transport purposes, even into the 2050s.

Neil Martin | 10:34

And I guess Andrew as well, even someone like Taylor Swift might not be able to afford the ticket, given all of those technical challenges that would need to be overcome.

Andrew Moore | 10:42

I look, it's-it's one of those ones, I think there was a period of time where SpaceX were saying, well, we can put, you know, 20 people in the payload module of one of their rockets. And you could argue that's travelling at hypersonic speeds. But the 20 G at launch is, you know, is a bit tricky. Asteroids do it. They go through a serious training programme. Taylor Swift probably goes through that training programme as part of her lead up into a global campaign. But hey, won't be for everybody. That's for sure.

Neil Martin | 11:08

So I think you're effectively ruling out these kind of, you know, two-hour intercontinental travel. You just don't think that's feasible, even in 2050?

Andrew Moore | 11:19

I think it's a little way off. But we'll see. I think there's certainly applications for other things. And I know, defence are interested in being able to get things to any part of the globe in a few hours. But typically, that's equipment, or very, very, very special trained, super humans.

Neil Martin | 11:37

Well, I think even fighter jets only go at Mach Six, top level, maybe Mach Seven full speed. So that's the kind of level of tech and development that is needed.

Andrew Moore | 11:48

Ah look, so, well, actually, the fastest operational fighter jet was Mach three, and it was actually a Russian jet. The fastest spy aircraft, of course, that was used quite a lot was the SR71. So you know, we've have seen those things can work.

Sonya Brown | 12:02

But not at hypersonic speeds.

Neil Martin | 12:05

So maybe at the other end of the spectrum, and you mentioned it before, Andrew is kind of this much more personalised travel. And also, I guess, much slower travel. And one of those things might well be people think about flying cars, they see that from science fiction, again, it's something that always seems to be 20 or 30 years in the future. Do you think that now we can say yes, 20 or 30 years in the future, there will be flying cars, or personalised transport via drones, for example?

Andrew Moore | 12:38

Yeah look, I think for many people watching this space closely, it's clear, there's a number of companies that are on the cusp of rolling these out in commercial applications. And we're one of the companies that are in that race. And certainly, there are lots of exciting things coming in the future. Now, they may not look quite like the Jetsons, and they may not look like a car, per se. But certainly, you know, what they deliver will be, you know, door to door type travel. And so that really opens up some exciting things. We know flying slower uses less power because power is force times velocity. And for those aeronautics students out there, you know, they'll know that drag is a function of velocity squared so...so fairly quickly, there is an advantage in flying slower from an energy consumption standpoint. So yes, I see personalised travel happening in the next few years, starting in little segments and rapidly becoming the future in 2050. I'd be more surprised that we don't see lots of them, then surprised if we do.

Neil Martin | 13:41

When you start saying there's going to be lots of these things I'm thinking, Sonya, that that might cause some problems as well. Traffic on the roads is bad enough, and obviously, you've got a little bit more space, and it's a little bit more dynamic up in the air. But there's also, I guess, challenges with having increased personalised vehicles flying around kind of regulations and rules and how that all actually works, logistically.

Sonya Brown | 14:07

Yeah, so I think we are going to see the first of these vehicles in the next few years. And the benefits are, most of these vehicles are being designed to have green energy, right, electrical and hydrogen energy. So removing fossil fuels, removing emissions, and technically should hopefully help ease that traffic congestion on the ground as well. But yeah, to do that there is a lot of work to go-to go from small numbers with qualified pilots flying them to having hundreds or 1000s that practically anybody can fly them with a licence at least no more difficult to gain than a driver's licence. So to do that, we have to have a lot of development in the automation space. We need to have these vehicles able to effectively talk to each other in the air to do collision avoidance basically automatically, and to have effectively, a new sets of air rules develop. As I say, I expect to start seeing more of this in the 2030s. And definitely by the 2050s, I, like Andrew, will be very surprised if we don't have lots of these vehicles, you know, flying above us.

Neil Martin | 15:19

Can you expect then that-that might also have an impact on urban demographics, I guess, if people are able to get around, maybe travel further distances in shorter periods of time with these kinds of vehicles. Does that change, where people might think they want to live or work?

Andrew Moore | 15:37

In a similar way, every generation of new transport technology...there has been a change in how cities have played out. And so if you think that, you know, the average person, the ideal is about a half an hour travel from home to work. And so if your commuting speed is 300 kilometres an hour, then that's a pretty large ring around our cities. So it blurs what is a city because, suddenly, you've got this high levels of connectivity. Now you combine that with the trends we're seeing with, you know, hybrid working with a bit of work from home and these sorts of things. So we'll see that as the technology evolves, so will the demographics and so will how cities function will change.

Neil Martin | 16:24

And one other thing maybe to throw in there as well that affects that...we've talked about these as kind of passenger vehicles that people would be flying in. But I guess there's also drone technology being developed and what the implementation of that might be. I think the thing that most people would maybe think about is drone delivery. I think, you know, some companies like Amazon have said that they would like to deliver parcels via Amazon. Sonya, in that kind of drone space, how do you think that will develop? And what applications are most likely in the next 30 years?

Andrew Moore | 17:02

So drones are expanding really rapidly right now. And it's almost hard to envision how much, you know, they could be doing for us in 30 years time. Drone delivery is certainly one. But again, you know, there is some airspace concerns with all of the things and how that's going to be managed. At the moment, I think there's a place in Queensland where they're doing drone delivery regularly. But drone delivery is just one thing. But I think one of the most potential, again, thinking about Australia, is looking at, you know, climate change is impacting the whole world. We've got the potential of delivering emergency supplies by drones in flood areas, we've got the potential of monitoring fires, or maybe in 30 years time fighting fires with drones. The potential of that is really exciting to me. In the last few years, we've had a couple of large aerial tankers unfortunately crash, and a few aerial firefighters lose their lives in Australia. So some of that kind of flying over disaster areas is some of the riskiest flying we've got, particularly when we're talking about fires in mountains. So being able to take our pilots out of those scenarios and have remotely piloted aircraft, going in and performing those critical tasks which are really important. And I don't see the fire situation really getting better with climate the way it is, you know, can really help society. So we've got a lot of potential there into the future.

Neil Martin | 18:35

Do you see drone technology, Andrew, as one of these things where once it becomes more developed and more common that people will just see more and more applications for it. And there'll be a real boom?

Andrew Moore | 18:49

Oh look, absolutely. So as we trust autonomy more...so once upon a time, there were people who operated lifts, and people wouldn't get on a lift unless there was an operator. Whereas you know, today, we're trusted to push the button, and it'll make it work. So in every aspect of human development over the last 1000s of years, we've found ways to to be more productive and avoid doing the more dangerous and mundane jobs and drones definitely open up lots of opportunities. And where things get really interesting, of course, is where we can divide whatever it is you're trying to do into a smaller and smaller and smaller parcel. And so because then you can have smaller and smaller and smaller objects doing that in ways that the consequences of something going wrong are really, really low. The same time... maybe you can fight a fire with 1000s of small drones that are loitering, waiting for the lightning to strike that suddenly converge where that lightning hit in a way that can put the fire out within minutes of it being lit. There are so many things that once we've got the first underpinning piece of technology working then so many of these options will come out.

Neil Martin | 20:00

Sonya, you mentioned there about potential legislation or just rules and regulations for both of you. Are you confident that those things can be done? Or would you have any concerns with the development of that to make these things safe and reliable?

Sonya Brown | 20:18

Look, I think regulations always seem to take a bit of time, but from what I'm seeing CASA, in Australia at least, are starting to look at these challenges. Now they're looking at least to the 2030s, maybe not quite to the 2050s yet. And they're talking about, you know, increased drones, increased advanced and mobility or flying cars, they're talking about these things already. So I do think the regulations will get there, maybe not necessarily as fast as everybody will like. But as I say, from what I see from CASA, they are at least looking to the future, and trying to work on. I think, in terms of safety...we have basic concepts in in aerospace or aviation of redundancy. So if one of those propellers fails, they actually have more engines to keep going. But obviously, with more of them than that increases risk. And yeah, it's about how to manage that, and particularly with some of these vehicles work out, okay, how the vehicle is going to react when something goes wrong.

Neil Martin | 21:20

See you nodding in agreement there, Andrew, with some of those points?

Andrew Moore | 21:24

Absolutely. So if you look, you know, aviation is the safest form of travel today. And arguably, being on a plane over the middle of the Pacific is the safest place you can be on the planet at any given point in time. You know, so the people who are responsible for keeping us safe, will look at this very carefully. They don't want to erode our trust in aviation. And so as a consequence, they will be cautious in the way they act. Today, we have what's known as segregated airspace. And so there's an area where drones can fly, there's an area where uncontrolled aircraft can fly and there's an area where controlled aircraft can fly. To the future will be a fully integrated airspace. But of course, it will take time and effort to build a systems and prove that they are safe before, you know, that becomes widespread. So, you know, we know they're looking at it. And we know, there's a lot of activity, but proving that you have one catastrophic event in a billion flight hours, takes a lot of work. A billion is a really, really long time.

Neil Martin | 22:24

Absolutely. Now, all of that might lead me on that you've mentioned some of the environmental issues that drones might help with but I guess there's an environmental issue with aviation in general. I think the stat is that around about 3% of global carbon emissions are created by the aviation industry. Obviously, it's quite important to reduce that number to as close to zero as possible. A lot of these individual flying vehicles, I presume, will be electric in the future. And I think you mentioned with regards to those passenger planes, the airline companies and the aircraft manufacturers are talking about hydrogen. How important is it for those developments to continue in that way? And how easy will it be to get that carbon emission number down to zero?

Sonya Brown | 23:19

I don't think it's going to be easy, but it's certainly one of the key challenges that the aviation industry really do care about. So hydrogen is a great fuel, and it can run the vehicles and on a per weight basis, it's actually better. But on a per volume basis, it's a lot worse. So we can't just go put hydrogen into existing, say, commercial passenger vehicles. There's just not enough room in the fuel tanks for the hydrogen required. So it basically means we need to design for new aircraft, and that that's not a short thing, right. So we, we need these, you know, at least kind of 10 year development cycles. So it is though why it's quite encouraging that say a company like Airbus that make a large amount of our commercial vehicles do have proposals for three different hydrogen based commercial aircraft they're looking into. In the 2030s. I'm really hopeful that we get some hydrogen commercial vehicles for those domestic style distances, you know, maybe up to 200 passengers. But I would say by the 2050s, which we're talking about, we have the potential to be able to get to those international distances, but it's still going to require full new aircraft, which we just don't have right now.

Andrew Moore | 24:38

Yeah so most of the world's flights are actually below 1000 kilometres. So it works out to be I think's it 60% are about the 1000 kilometre distance. So that means that you can have a significant impact, as Sonya said, definitely long range aviation. There's a lot of great work going on, but it will take a long time. There's a lot of people pinning their hopes on sustainable aviation fuel. The challenges with that, of course, is sustainable aviation fuel, in some cases, requires feedstock that come out of food production. So the worst case scenario is it drives up food prices or encourages more palm oil plantations in the tropics. The best case scenario is they make efuels, in which case you require more energy than just making hydrogen to make a fuel. Longer term, I think hydrogen long range aviation will happen, whether it happens by 2050 is a..is a big question mark. In the near term, biofuels does a bit but I think there's that up to 1000 and I'd say 2000 kilometre range is the sweet spot for technologies like hydrogen with hydrogen fuel cells, and a bit of hydrogen combustion, and that is burning hydrogen in a conventional engine. There'll be, you know, a number of technologies on that front, but electrification offers some great opportunities to really change the way we do it and change how much it costs to do it.

Neil Martin | 26:02

But do you think for electric vehicles, they would have to be on the smaller side, because for those large planes, the battery size would just have to be too big, or you just don't get enough energy in those batteries to be able to power those planes over those distances? Is that a correct assumption?

Andrew Moore | 26:22

Look, I actually struggle a bit with pure battery aircraft. I think if your flight time is greater than 20 minutes, you're going to struggle with a pure battery aircraft, there's a number of challenges with batteries, their energy density is high, the batteries that have both good energy density and good power density, which is what you need for an aircraft. If you want to have a good life, which is what you need for low cost, then you're recharging them slowly. And so you end up in this place where you can have two of any. You can either have fast charge and low energy density or, but it's really hard to get all three. And that's what makes batteries hard. Which is why I think technologies like hydrogen with hydrogen fuel cells is better suited to today's aviation market. So that's, I guess, my brief view on those things.

Sonya Brown | 27:09

Yeah I just wanted to, I guess, add, yeah, I think a combination of hydrogen and battery is very likely in those smaller distances, like Andrew has said, but I wanted to write some additional comments on the sustainable aviation fuels or biofuels. So why these are...I consider them a stopgap solution. Rather than a long term, 'this is what we expect to be doing' because they are sustainable in that they are recreatable, they're not coming from a non renewable resource. It's a renewable resource, right, we grow things, but they still have an emission. So what we really want to get to is practically zero emissions. So while they're sustainable, we're not using non renewable resources, they still have very similar kind of emissions. And at least currently, we're mixing in sustainable aviation fuels with the existing fuels to make sure we've got the power density. So while we may be able to increase the power density of the sustainable aviation fuels, it doesn't solve our emissions problem. So the long term, and when we're talking about 2050s, we really don't want those emissions still. So while we could create our fuels in a renewable sense, we want to cut the emissions as well, which is why, as an overall, we would prefer to lead towards things like hydrogen, which really cut the emissions, as well.

Neil Martin | 28:33

So I wanted to ask a question, and I hope you don't think it's inappropriate. But maybe when people hear hydrogen in a flying vehicle, their mind might go to Hindenburg, which was obviously a long time ago, but it is etched in people's memories and that famous video and the pictures of this airship burning up, because I believe some leaking hydrogen ignited and caused a big fire. What would you say to people who might then automatically think, 'oh hydrogen in a plane doesn't sound like the safest kind of fuel to progress with'?

Andrew Moore | 29:11

Yeah look, so I certainly get this question a lot. And so, you know, if you look at the Hindenburg disaster, you know, tragedy that it was...hydrogen is very, very like gas and it escapes very quickly. And so, you know, there was a hydrogen sort of fireball that essentially was completed within the first few seconds. Half the people who died in that accident died jumping from that particular airship, and the other half died from the paint. The paint was a bituminous paint, and it falling on them and suffering from burns from that. And so, so nobody died from a hydrogen burn. Now, that doesn't mean that hydrogen wasn't a contributor to that particular accident. Certainly, you know, the world has moved on quite a lot from then. Hydrogen as an industrial gas is one of the biggest trade commodities in the world. We use it in lots of things. It's used a lot in fertilisers and funnily enough in fossil fuel production in removing sulphur out of fossil fuels, but it's also been used extensively in cars, buses and trucks. And so there's been a lot of work to ensure that any fuel can be carried safely. Now, I've been in the aviation industry for a while. And aviation fuels are toxic stuff, you know, 20 years ago, there were all of these poor maintainers, who've been working in fuel tanks for a large part of their career

Sonya Brown | 30:31

in the F1-11s.

Andrew Moore | 30:32

Yeah, having horrendous diseases as a consequence of working with aircraft fuel systems. And look, some aircraft, some piston aircraft today use fuel which has lead in it so...so the question shouldn't be is hydrogen safe? The question should be are fossil fuel safe?

Neil Martin | 30:50

I was just going to pick up on your point there, Andrew, which I think is massively valid that, you know, Hindenburg was 1937. We're almost 90 years down the track. Now, the safety and the development of these fuel systems is obviously improved massively, Sonya, and you would echo Andrew sentiments, I guess, in terms of the safety.

Sonya Brown | 31:13

Yeah, so obviously, hydrogen is flammable as we need it to be to be able to be used in combustion. But as is, I guess, every other fuel we currently use, and particularly obviously, when mixed with air. So, effectively, design of systems with hydrogen does have to be a bit different, because it is flammable. So there's a lot of design now around the storage of hydrogen and how to store that safely, how to transfer that safely around the vehicle, and ignition source management. So yes, it's flammable. Yes, we have to be careful what we just need to design to that. And we have been designing systems with very similar parameters in how we use jet fuels at the moment.

Neil Martin | 31:55

You mentioned before that the entire design of planes might need to be amended with potential new hydrogen fuel systems in place. I think I asked you before about whether or not more comfort might be on the cards in 2050. Do those design aspects change anything in terms of the experience that people might expect on board an aircraft in 2050? ,

Andrew Moore | 32:21

Yeah look, so we designed and built an aircraft which had sufficient volume for hydrogen in a way that didn't have an impact on performance. And it uses a configuration known as the box wing, which is really an evolution of Lawrence Hargraves box kite, if you can use your apply your imagination appropriately. But look, certainly, you know, there things that will be done in other aircraft designs as well, that will accommodate those types of fuels. From a ride-comfort perspective, well, once you've got an aircraft that doesn't produce noxious gases and exhaust, then maybe you can all load and unload from inside a building. Some of the smaller aircraft, people still wear headsets, I'd say, a lot of the small aircraft will remove the need for headsets with electrification. So that's, you know, on hearing protection, so that will be nice. The noise around airfields should reduce with some-some of the opportunities that electrification brings. So that will be nice for people around the aircraft. All of our modelling today shows that when our aircraft over flies, then it will be near an audible, so the ground noise will mask it completely. And so that will have some interesting impacts on the surrounding community. Now, when we start looking at automation, automation will open up some opportunities to do what's known as gust alleviation and that is, you know, in the sky, sometimes it's bumpy. And that's typically by you know, turbulent air. As we get more automated with our flight control systems, we can have gust alleviation which essentially makes the flight much, much smoother for the passenger, but also has benefits to the airframe life so it can make it lower cost as well.

Neil Martin | 34:00

Sonya, do you see any major changes to the experience of people onboard the plane. Andrew makes a good point that hopefully, people living in and around airports should get some benefit.

Sonya Brown | 34:14

On-board you know, the commercial airliners, I guess from what I see, I don't really see a massive change in the on-board experience because in terms of, you know, passenger spacing and those kinds of things for these, these hydrogen commercial level vehicles, you know, we still expect those similar passenger spacings for economy or business and the like. They may, for the same size of aircraft, in terms of, like if I consider an aircraft length, they're going to carry less people, most likely because of that, you know, extra hydrogen storage that is required. But what we know is all engines sound different. So I do think that that is going to have impact because we know the engines and the fuel changes the noise. We already see that with our electric cars, that we have those noise changes. Obviously, as a different angle, though, we're also talking about adding more aircraft to our skies, which does have some noise impacts. But again, there's research ongoing in how do we reduce noise from propellers, for example, to try and reduce that, to a minimum and make sure that there's limited impact. So there's basically various areas of development going into these vehicles such that it would be acceptable to have these smaller vehicles flying in larger numbers above our cities.

Neil Martin | 35:40

I'm just trying to imagine the sound of 1,000 buzzing drones in a small space. You've suddenly sparked my imagination in that regard, Sonya.

Sonya Brown | 35:52

Trying to minimise it before it's that many.

Andrew Moore | 35:54

Fortunately, it will never sound like 1000 buzzing drones. It's more at a low hum than an annoying buzz.

Neil Martin | 36:00

Thank you for for clarifying, Andrew. We talked about new fuels there with regards to hydrogen and more electrification. I wanted to ask about other new innovations, maybe new materials that are being developed for the manufacture of aircraft. I read something about shape memory alloys, but I was struggling to understand what that was specifically, but maybe you could inform me and talk about some of the other material science developments that are happening in this space.

Sonya Brown | 36:32

So a shape memory alloy is effectively one of a larger class of materials that we would consider morphing materials. So shape memory alloys are typically a metallic type that will effectively change its position based on temperature. So at one temperature, it will be effectively in one position. And when it reaches a threshold, it will deform to then be and stand in another position. So you'll have a biometallic strip, which if a certain temperature is reached, it's going to separate, which helps you alert that there might be a fire and you can set off an extinguisher in that aircraft engine remotely. So, on the base level, it's not really new technology, but we can use such materials and shape memory alloys metallics are one. So what this could potentially do, what we'd like it to do is, you know, you could instead of having a traditional control surface, which is let's say off the back of your wing, you could have that all integrated in the wing structure, and you can just send effectively electrical signal and the material will do the deformation for you that would be really ideal, it would reduce things like drag and make our aircraft more effective. So you can do things like that in the morphing space. There's also a lot of other materials being mentioned, as Andrew mentioned earlier, we're looking at a lot of structural energy storage. So this is trying to integrate both battery energy or super capacitor energy into our materials. So if we can make structures that have other functions, and they can help basically run your aircraft or as a super capacitor, just provide power for a particularly high instance, you can then reduce the overall system weight, making you either take less fuel or go further or carry more. There's also a lot of work. Again, we've spoken a little bit about fire today. So we can also integrate some of those materials into composites to improve their fire resistance, improve their fire retardancy to help if there is an instance of fire to help it basically die down quicker, or improve the reaction of the structure to something like lightning strike.

Neil Martin | 38:46

And Andrew, I see you nodding there. As Sonya said, these new materials are going to change the potential weight, the potential efficiency, does that also then lead into some new design elements? Can people expect planes to look quite different in 2050? Or do you think that they will generally look the same?

Andrew Moore | 39:10

So I think I've previously mentioned, our aircraft is a bit unconventional in the way it looks, being able to do little things.

Neil Martin | 39:17

And can you explain that in an audio way? Unfortunately, we probably don't have visuals.

Andrew Moore | 39:22

Yeah, for sure. If people can picture a box wing, which is a front wing and a rear wing with the two wing tips are connected. Now, if you then spread those out horizontally so that you've got a wing at the front of a fuselage and the wing at the rear of a fuselage. The one at the front is down low, the one at the rear is up high. And then a pod-like structure, the wingtips and then a fin that joins everything together. And so it's a continuous wing as you go around. So it's an example of an aircraft that has a different look to a conventional aircraft. Now incorporating things into your aircraft structures that have electrical function is a great way of, you know, being tightly integrated and saving weight. And so an example of that with greater electrification, you need to transmit power from where your energy storage is to where it's being used. And so there's lots of these attributes, which will make it easier to electrify aviation and solve the problems that that many electric aviation companies will find.

Neil Martin | 40:25

So I started this podcast with the question about speed, which I think most people are interested in. I might loop back and think that another thing that people are, are interested in is cost. When we take in all of these things that we've spoken about, the new materials, the new fuels, the speed, the efficiency...do you expect the cost of a plane ticket to be reduced massively in 2050, or the same, or all of these things gonna have to be paid for by the passengers?

Andrew Moore | 40:58

I was gonna say, I think with this one, there's a few things that depends. So if, if our large airliners and our large manufacturers do nothing, then the cost will go up. And that's because governments will be forced to put large taxes on it to stop people from flying. If our technology and what we're trying to do come to fruition, then you will see a rapid reduction in the cost of flying. And as you know, the combination of automation and electric flight using renewable green hydrogen has the opportunity to drive operating costs, and therefore ticket costs, to levels where it's we're talking train ticket prices to get between Sydney and Melbourne as opposed to current airline ticket prices, which are quite exorbitant compared to historical norms.

Neil Martin | 41:44

Do you agree Sonya?

Sonya Brown | 41:46

I'm not a business person. So I, you know, obviously, fuel is a large cost. So if we can get cheaper fuel that will have an impact for commercial flight, we, we are still going to see the crews. So that's another cost. So it has potential to reduce the cost definitely on a fuel basis. I can agree with that. But overall cost, and then you add in inflation, can I say a ticket in 2015 is going to be cheaper than today. A bit too economical for me.

Neil Martin | 42:14

And it's all relative, I guess, who's to say that it won't be more expensive, but you know, on paper, also cheaper, if that makes sense, relative to cost of living and all of that kind of thing.

Sonya Brown | 42:26

That's kind of what I was trying to get at.

Neil Martin | 42:30

Look, you've mentioned a lot of things there. And there's obviously a lot of different areas that are being developed. And I wanted to ask you both, if you were a 16 or 17 year old today, thinking of going into the aviation industry as a career, what would you be most excited about?

Andrew Moore | 42:48

If I was a 16 and 17 year old, I'd be really excited about the opportunity for personalised transport and where that will take us to, and I'd be excited about where does door to door and Vitol transport end, because I think there's a great range of opportunities for that part of technology to really drive us into the some--I'd say almost jetpack like experience, I suppose. So I'd be excited by that.

Neil Martin | 43:14

And for you, Sonya.

Sonya Brown | 43:16

So I guess I come from a place where I can't understand why any 16 or 17 year old wouldn't be excited about the future of flight because in reality flight is super cool. As humans, we weren't, you know, made to fly, that was the birds, but we're doing it anyway. But in terms of the opportunities in the future for that generation, from an engineering perspective, all the stuff that we've talked about here is, you know, these kinds of vehicles and the light that could be developed in the future. And aerospace is a really dynamic field. It's not like you're going in and you're looking at one thing and look at you know, what, what our skies might look like and how we can improve travel into the future. So I just think there's so many exciting opportunities, not like you're just getting into one thing, right? There's such a range of options to help flight towards 2050.

Neil Martin | 44:09

I absolutely agree. Sonya, and there's so many aspects to this. And I'm really grateful for both of you for explaining a lot of those developments that are going to happen. And it sounds like a really exciting thing, not just for young people but for everyone. It's been an absolute fascinating discussion, Dr. Sonya Brown, many thanks for making the time to join us.

Sonya Brown | 44:30

Thanks, Neil.

Neil Martin | 44:31

And thanks also to Andrew Moore. It's been a pleasure to chat to you.

Andrew Moore | 44:35

Thank you very much, Neil.

Neil Martin | 44:37

Unfortunately, we're now in the departure lounge. And that's all we've got time for. Thank you for listening. I've been Neil Martin and I hope you'll join me again soon for the next episode in our Engineering the Future series.

Voiceover | 44:53

You've been listening to the UNSW Engineering the Future podcast. Don't forget to subscribe to our series to stay updated on upcoming episodes, check out our show notes for details on in-person events, panel discussions and more fascinating insights into the future of engineering.