Can passenger airships make a triumphantly 'green' comeback?
Large airships were too sensitive to wind gusts and too sluggish to win against aeroplanes. But today, they have a chance to make a spectacular return.
This trend brings with it the unique opportunity for the much more environmentally-friendly passenger airships to make a triumphant comeback. Much like they did 100 years ago, today's airships move with the help of propeller-type turbines powered by petrol or diesel engines. However, they emit considerably less CO2 than jet engines. On shorter distances, their speed, on average nine times lower than passenger jets, does not make that much of a difference. Especially since an airship can pick up passengers even in the centre of a metropolis.
Working on refining such a solution is the British company Hybrid Air Vehicles (HAV), founded in 2007. For the past decade, its engineers have been fine-tuning the Airlander 10 project. Standing behind the name is a 92-metres-long vehicle that combines the benefits of an aeroplane and helicopter. It can land and take off from practically any location, take 14 tons of cargo or 60 passengers on board, and then fly at a speed of 140 kilometres per hour for up to five days without having to land. In September 2019 in London, HAV representatives signed a contract with the US company Vertex Aerospace LLC, thereby opening up the possibility of supplying Airlander 10 to the US Department of Defense. Soon after that, the management of HAV announced it was launching preparations for the development of a passenger model powered by electric engines. It is indeed this type of drive unit that could ultimately tip the scales and let these huge machines, the development of which was halted by aeroplanes 100 years ago, take to the skies once more.
A balloon with an engine
The balloon designed and built by Joseph and Jacques Montgolfier never became a useful flying machine due to one fundamental drawback: the direction that it flew in was defined by the blowing wind. For several decades since the summer of 1783, when the brothers held a demonstration of their invention for King Louis XVI by sending a lamb, rooster and duck flying in the air, designers were not be able to overcome this challenge. Granted, there were designs of balloons equipped with sails or even propellers, yet the secret to success lay in a proper drive unit.
French designer Henri Jules Giffard was the first to recognize this. He managed to build a steam engine weighing a little over 100 kilograms that could be installed in the balloon's gondola. He attached his structure to a cigar-shaped balloon 44 metres in length and filled it with hydrogen. Then he loaded 150 kilograms of coke into the gondola and, on 24th September 1852, set out from Paris to Trappes. The flight proceeded in the direction chosen by Giffard, as the French inventor equipped the vehicle with a triangular sail serving the function of a rudder. Yet the flying giant proved to be helpless in the face of slightly stronger gusts of wind. And once again, the problem lay in the drive unit; to be able to squeeze additional power out of a steam engine, it had to be enlarged. That, in turn, meant that the balloon needed to be bigger to be able to lift the heavier load into the sky. But then the vessel would become even less controllable and vulnerable to the wind.
Numerous designers attempted to improve Giffard's masterpiece. An airship designed by two captains of the French Army, Charles Renard and Arthur Krebs, looked very promising. The propeller that pushed the vehicle forward was powered by an 8.5 horsepower electric engine, eight times more powerful than Giffard's steam engine. Thanks to the new drive unit, on 9th August 1884, La France was able to fly eight kilometres in 20 minutes, turn back and return to the place it started from, in spite of the wind. However, Krebs and Renard were not able to manage the issues created by lead acid batteries, as they were too heavy, inefficient and required constant recharging.
The flying count
While French inventors were walking in circles, the Germans set off to conquer the heavens. At the end of the 19th century, Germany was producing the most sophisticated combustion engines in the world. The small yet powerful 28 horsepower engines from the Daimler factory caught the attention of Count Ferdinand von Zeppelin. In 1890, with his 50th birthday on his heels, General von Zeppelin decided to end his military career and engage in the construction of flying machines, thereby fulfilling the dreams of his youth. He caught the aeronautics bug in the US during the Civil War, when he flew in a balloon high above the battle fields as the envoy of the King of Württemberg. 25 years later, he started work on the construction of an innovative airship along with engineer Theodor Kobert. They drew inspiration from the ideas of Hungarian engineer David Schwartz, who had patented the design of an aerostat based on a stiff frame covered with a cotton or aluminium shell, which in turn concealed soft balloons filled with hydrogen.
The fulfilment of his dream proved to be a costly venture, and after eight years of struggling, Von Zeppelin founded the Gesellschaft zur Förderung der Luftschiffahrt in Stuttgart in 1898. In July 1900, on the coast of Lake Constance, he was able to present to shareholders and onlookers his enormous flying machine, the Luftschiff Zeppelin (LZ 1). The cigar-shaped creation, which was 128 metres in length, majestically glided across the sky around 300 metres above the waters of the lake thanks to two Daimler engines. Following that success, and thanks to public fundraisers and lotteries, Von Zeppelin managed to collect 250,000 marks to build yet another airship, abbreviated the LZ 2. The count was expecting that the German army would buy it for 1.5 million marks, but the price proved to be prohibitively high. The army was initially not interested in the LZ 3 model either, although it made 45 flights safely, covering an air distance of 4000 kilometres.
A breakthrough did not come until the matter of the high-profile catastrophe of the LZ 4 airship appeared. The count had turned the LZ 4 into a near masterpiece. The 136-metre-long cigar-shaped vehicle was divided into 17 chambers filled with hydrogen, and attached beneath it was a gondola for the pilots and mechanics, as well as a second luxury passenger gondola. Even King Wilhelm II of Württemberg, who had been persuaded to try the airship out in July of 1908, had no complaints about its level of comfort. After the marketing success, Count Zeppelin announced that his vehicle would make a 24-hour flight without landing, hoping to convince the head of the German army that airships were the perfect solution for attacking the deep hinterland of the enemy. However, on 5th August 1908, a storm forced the LZ 4 pilot Hugon Eckener to land near the city of Echterdingen. There, a gust of the storm wind snapped the airship's tether and threw it to the ground; the hydrogen exploded and the machine burned to ashes.
That loss pushed Count Zeppelin's company to the brink of bankruptcy. When the news became widespread, the Germans spontaneously organized a fundraiser for the engineer, whom they were proud of. Soon, he received a sum of over six million marks. This capital allowed Zeppelin to found Luftschiffbau Zeppelin GmbH, a company that, in line with its name (Luftschiffbau means 'airship engineering'), specialized in the construction of airships. Financial aid was also promised by the Minister of War Karl von Einem, who was increasingly more interested in the combat potential of the flying machines.
Civil and bomber
The mass participation of regular Germans in the fundraiser gave Von Zeppelin the idea that his airships could compete with train travel. In November 1909, he surprised the world by founding the Deutsche Luftschiffahrts Aktiengesellschaft (DELAG) passenger airline. DELAG transported the first 20,000 passengers for free, thereby promoting the trend for air travel, and after that he offered tickets for 200 marks. The amount was equivalent to average monthly wages in Germany at the time; nonethless, its flights were becoming more and more popular. On board the 12 DELAG airships, servicing routes connecting the 10 largest cities of the German Empire, you could travel in the company of aristocrats, politicians, millionaires, generals, or even members of the Imperial Family. In 1914, the airline proudly announced that it had transported 34,000 passengers, and that not one of them died during the flights. Users of highly unreliable aeroplanes could only dream of such statistics at the time.
So when World War I broke out, as the late Walter J. Boyne wrote in his book The Influence of Air Power Upon History, "Germany was so convinced of the potential of dirigibles [...] that it allowed the Army and the Navy to develop their own airship fleets [...]." Ferdinand von Zeppelin, now nearing 80 years of age, was at the height of his fame, while his factories were working at full capacity. Right after the airships, commonly referred to as Zeppelins, appeared over the front lines in France and Great Britain, they raised alarm. In September 1914, in an attempt to anticipate any actions of the enemy, the First Lord of the Admiralty Winston Churchill planned a series of attacks of British bombers on airship bases in Cologne and Düsseldorf, and on an airship manufacturing plant in Friedrichshafen. Despite the great dedication of the airmen, the action brought little effect, as only one Zeppelin burned down on the ground when it was hit by a bomb. Yet the expected retaliation attacks did not take place right away. "At a joint meeting September 1914, representatives of the Army and Navy decided that there were as yet too few airships to bomb England, and further, that they were inhibited by Kaiser Wilhelm's reluctance to bomb the homes of many of his royal relatives," Boyne explains. It wasn't until Germany realized enormous losses on the front that the monarch changed his mind.
"The first attack took place on January 19-20, 1915, with two out of three Zeppelins – L 3 and L 4 – successfully reaching England," Boyne describes. L 3 dropped over a dozen 50-kilogram bombs on Great Yarmouth, while L 4, led by Captain Magnus von Platen-Hallermund, nearly gave the German Emperor a heart attack. Its bombs fell onto Sandringham House, where the cousin of Wilhelm II, the British King George V, happened to be staying at the time. Luckily nothing happened to him, but the public were shocked by the fact that for the first time in 800 years, since the times of William the Conqueror, an enemy from the continent had launched a direct attack on the monarchs of England.
At first, the airships operated over the island with complete impunity. Rifle bullets shot from the ground were not able to pierce the duralumin sheeting of the vessels' hulls. In addition, Zeppelins flew at higher altitudes than fighter planes and were able to climb up more quickly, in spite of their large dimensions. For the first time ever in history, Lieutenant Reginald Warneford managed to shoot down the L 37 airship, but this was only after he flew above it in a plane and dropped six bombs from the top. Therefore, the Germans used them even more boldly. "All the fears seemed to be realised on the night of October 13-14 , when five Zeppelins slashed across England, dropping almost two hundred bombs and killing seventy-one people and injuring another 128," Boyne reports.
The blind path of evolution
"Looking up the clear run of New Bridge Street and Farringdon Road I saw high in the sky a concentrated blaze of searchlights, and in its centre a ruddy glow which rapidly spread into the outline of a blazing airship. Then the search lights were turned off and the Zeppelin drifted perpendicularly in the darkened sky, a gigantic pyramid of flames, red and orange, like a ruined star falling slowly to earth," are the words reporter Michael MacDonagh noted in his journal entry dated 1st October 1916. "It was so horribly fascinating that I felt spellbound – almost suffocated with emotion, ready hysterically to laugh or cry. When at last the doomed airship vanished from sight there arose a shout the like of which I never heard in London before – a hoarse shout of mingled execration, triumph and joy; a swelling shout that appeared to be rising from all parts of the metropolis, ever increasing in force and intensity," he added. A month earlier, right after midnight on 3rd September 1916, London experienced the 'Night of the Zeppelins', when as many as 16 dark cigars hovered over the British capital, each 200-metres long and each dropping bombs to the ground. They seemed to be mighty and impregnable, yet as a result of the wartime arms race, planes and anti-aircraft artillery was being perfected at an amazing pace. A few months down the line, all you needed to take down an airship was an accurately launched machine gun series with ammunition designed to puncture the aluminium shell, or a few artillery shells. When British fighter planes shot down 17 Zeppelins in 1917, the Germans backed out of the London bombings.
The bombs dropped by the airships killed 557 British subjects and caused material damage amounting to $7.5 million. Yet the construction of 17 Zeppelins cost $8.3 million, and over 300 crew members were lost. From a military and economic perspective, the balance was disastrous. Nevertheless, in the Versailles Treaty, the triumphant superpowers prohibited the production of airships in the Weimar Republic.
Fortunately, Ferdinand von Zeppelin did not live to see that day, as he had died in 1917. His successor at Luftschiffbau Zeppelin GmbH, Hugo Eckener, initiated long-term lobbying efforts in the US that lasted until 1922, when American President Warren G. Harding stated that it would be an excellent idea for Germany to pay out part of the war reparations due in brand new airships. London and Paris did not protest to this. In the meantime, engineers had developed a new generation of machines. The first LZ 120 series airship 'Bodensee' had the shape of a 120-metre-long 'teardrop', which was able to fly at a speed of 130 kilometres per hour thanks to four Maybach engines with 245 horsepower each. An improved version of the 'Bodensee', the LZ 127 'Graf Zeppelin', was extended to 236 metres. As a result, it allowed engineers to achieve a significant increase in lift, to the point where in 1929, humanity could follow the flight of the 'Graf Zeppelin' around the world with fascination. At the time, the press was all over the topic of its comfortable cabins for 40 passengers, which were even equipped with separate toilets and showers with hot water, a luxurious restaurant and a lounge, indispensable for evening receptions.
But not too long after that, the factories of William E. Boeing in Seattle started to offer to airlines its innovative passenger aeroplane model, the B 247; it was a beautiful twin-engine machine able to fly at speeds of over 300 kilometres per hour. It provided a sound-proof cabin for 10 passengers with the possibility of controlling the temperature. But it didn't outbid the offer of luxurious airships just yet; the decisive factor in this new race was... gas. German engineers replaced the flammable hydrogen with the much safer helium. They had to buy it from the Americans though, as only they had the technology available to produce helium on an industrial level. When Hitler came to power in Germany, fears were increasingly expressed across the Atlantic that a fleet of combat airships could launch an unexpected attack on American cities and ports. To the great joy of Boeing, President Franklin D. Roosevelt introduced an embargo on the export of helium to the Third Reich. So Zeppelins would once again be filled with hydrogen. The explosion of hydrogen during a landing at the airport in Lakehurst (New Jersey) on 6th May 1937 destroyed the LZ 129 'Hindenburg'. The catastrophe, in which 35 people were burned alive, resounded to the point that potential air travel buffs lost all trust in airships. It wasn't such a great sacrifice for them though, as only a few months after the 'Hindenburg' had burned, Boeing offered them the four-engine B 307 'Stratoliner', the first passenger plane with a pressurized cabin that was able to fly at an altitude of nearly 8000m and had a range of 3800 kilometres. Airlines no longer needed the giant cigars. The army used them for third-rate patrol operations at sea and as barriers attached to cables to make it harder for bombers to attack cities.
That's how the age of the airship came to an end, but maybe not an indefinite end. According to the study concept by Hybrid Air Vehicles, the new generation vessels would be powered by electric engines supplied not only by energy from batteries, but also by energy from solar panels. That would allow the vehicle to embark on flights lasting several days continuously, not to mention neutrality for the natural environment. And that advantage can only gain importance in the very near future.
Translated from the Polish by Mark Ordon
The drive would provide enough thrust for a spacecraft to travel near the speed of light using only electricity, says physicist Jim Woodward.
- The thrust system utilizes piezoelectric crystals, which vibrate extremely rapidly when exposed to electric current.
- Early tests have yielded mixed results, but Woodward and his colleagues say a recent breakthrough related to the design of the thruster mount greatly increased thrust.
- Independent teams of scientists will likely test Woodward's design after the pandemic.
From health concerns to funding, there's no shortage of obstacles preventing humans from traveling beyond our solar system. But the main obstacle is propulsion: Our spacecraft are simply too slow and too reliant on fuel to realistically make a voyage to Alpha Centauri, the closest star to our Sun.
So, what do we need? Something like a reactionless drive — an engine that moves a spacecraft without exhausting a finite stock of propellant. So far, such a device only exists in science fiction. But for the past few decades, physicist Jim Woodward has been trying to change that.
The 79-year-old physics professor has developed a thruster design that he hopes will serve as a proof of concept for how humans can someday achieve interstellar travel. Called the Mach-effect gravitational assist (MEGA) drive, the device only requires a source of electricity to achieve thrust.
Early tests have shown mixed results. Woodward himself was only able to demonstrate miniscule amounts of thrust, while other teams reported little to no thrust when trying to replicate his experiments. Still, the design intrigued NASA enough to award Woodward $625,000 in funding between 2017 and 2018.
What's more, in 2019 Woodward and his collaborator and fellow physicist Hal Fearn reported a major breakthrough after redesigning the thruster's mount — a tweak that produced "more than 100 micronewtons, orders of magnitude larger than anything Woodward had ever built before," as a recent feature in Wired notes.
(To be sure, the level of thrust we're talking about is barely enough to visibly move an object across a table. But if the results are confirmed, it would suggest the technology could be scaled up.)
A heterodox view of inertia
Woodward's system is based on ideas that 19th-century physicist Ernst Mach proposed about inertia, which is an object's tendency to stay at rest unless acted upon.
In simple terms, Mach's principle argues that distant matter causes local inertial effects. So, a star in a far away galaxy has some effect on the inertia you encounter when you push a shopping cart. That's the idea, anyway. (Woodward gives a comprehensive breakdown of his views on Mach's principle in this blog post.)
In the 20th century, Albert Einstein incorporated Mach's ideas into his theory of general relativity, essentially arguing that gravity and inertia are fundamentally linked. But the broader physics community later rejected this view of inertia, largely because of a 1961 paper that showed inertia to be unrelated to the gravitational influence of distant matter.
Still, Woodward believes Einstein had it right all along, and that, under this framework of inertia, it's possible to develop propulsion systems that require only an electrical charge, not fuel. The key element of his thruster is a stack of piezoelectric crystals, which produces an alternating electric field when voltage is applied to it, as Woodward explained:
"Piezoelectric crystals are electromechanical devices, which means that when you apply the voltage, they mechanically expand & contract depending upon the sign of the voltage. So by applying a voltage, you're causing an E/c² energy fluctuation in the stack no matter what they do mechanically, and you're also producing an acceleration because of the changing dimensions of the stack due due to electromechanical effects, which also causes the acceleration required couple the device to the large gravitational field."
"The trick is timing the energy fluctuations and mechanical oscillations correctly, which requires using two frequencies — at the first and second harmonics, and it's the second harmonic that actually produces thrust."
Woodward and his colleagues have even drawn up plans for a spacecraft that would utilize the MEGA drive. Called the SSI Lambda, the craft would feature piezoelectric crystals and a small nuclear reactor to produce electricity.
"The SSI Lambda probe using MEGA drive thrusters is a truly propellantless-propulsion spacecraft," the team wrote of the design in its report to NASA. "It can travel at speeds up to the speed of light in a vacuum with only consumption of electric power. No other method for travelling to the stars and braking into the target system has been put forward to date, which also has credible physics to back it up."
After the COVID-19 pandemic settles down, other scientists and engineers hope to put Woodward's designs to the test. The results of those experiments should reveal whether he's onto something. To some experts in the field, the odds are slim. But that doesn't mean it's not worth investigating.
"I'd say there's between a 1-in-10 and 1-in-10,000,000 chance that it's real, and probably toward the higher end of that spectrum," Mike McDonald, an aerospace engineer at the Naval Research Laboratory in Maryland, told Wired. "But imagine that one chance; that would be amazing. That's why we do high-risk, high-reward work. That's why we do science."
Otto Aviation says the hourly cost of flying the new Celera 500L is about six times cheaper than conventional aircraft.
- The unusual shape of Otto Aviation's Celera 500L was designed to maximize laminar flow.
- Laminar flow is the smooth flow of air over an aircraft's wings, and optimizing laminar flow can make aircraft incredibly efficient.
- The plane can hold up to six passengers, and is expected to hit commercial markets around 2025.
An American aviation company claims to have designed an ultra-efficient plane that could someday make the cost of private flights comparable to flying commercial.
Otto Aviation says it's completed 31 successful test flights of its new Celera 500L, a.k.a the "bullet plane." According to the company, the plane features seats for six passengers, a 4,500-nautical-mile range and a top cruise speed of 460 miles per hour. That means it could fly nonstop from New York City to Los Angeles in about the same time as a conventional private aircraft.
But most notable is the low flying cost of $328 per hour. Compare that to the $1,300 to $3,000 hourly cost you and several friends would currently pay to charter a private jet.
How is the price so low?
It's mainly because of the plane's unusual shape. The cylindrical fuselage is especially aerodynamic because it maximizes laminar flow. Laminar flow occurs when air flows smoothly over an aircraft's wings, which reduces drag and boosts fuel efficiency.
Otto says the Celera 500L requires about one-eighth the fuel of a conventional jet.
"The design of the Celera fuselage takes advantage of an optimum length-to-width ratio to maximize laminar flow," Otto Aviation wrote on its website, adding that the design results in a 59-percent reduction in drag compared to similarly sized aircraft. "These benefits will not scale for large jet transports and are therefore well suited for an aircraft like the Celera."
Other specs include:
- Glide range of 125 miles at 30,000 feet, which is roughly three times better than conventional aircraft.
- Fuel efficiency levels that are 30 percent better than FAA and ICAO target emissions standards for aircraft entering service after 2031.
- Liquid-cooled V12 engine, twin 6-cylinder bank, capable of independent operation with mutually independent critical engine sub-systems for each bank.
"We believe the Celera 500L is the biggest thing to happen to both the aviation and travel industries in 50 years," William Otto Sr., the Chairman and Chief Scientist of Otto Aviation, said in a statement. "Beyond using our aircraft for passenger travel, it can also be used for cargo operations and military applications. Since the results from our prototype test flights have been so promising, we're ready to bring the Celera 500L to market."
The company hopes to deliver the Celera 500L to market around 2025, pending FAA certification. If successful, manufacturers like Otto Aviation, Transcend Air, and Airbus could usher in the era of air taxis, where people hail aircraft like they do taxis or Ubers. Paris, for example, was planning to have flying taxis in time for the 2024 Olympic Games, though it's unclear whether the pandemic will affect the project.
As far as how COVID-19 has affected the launch of the bullet plane?
"We didn't anticipate Covid-19," Otto told CNN. "But there are enhanced market opportunities in being able to afford to fly with only those you choose to. Being able to avoid crowded airports and lines is another big benefit. [...] In many cases, individuals and families will be able to charter the Celera 500L at prices comparable to commercial airfares, but with the convenience of private aviation."
The Earth Return Orbiter is part of a long-term mission to search for ancient alien life on Mars.
- On July 30, NASA is set to launch the Perseverance rover toward Mars on a mission to search for biosignatures of ancient life within the planet's Jerezo Crater.
- The soil samples collected by the rover would then be launched from the Martian surface into orbit, where a European-made "cargo ship" will intercept the container.
- The cargo ship — a satellite called the Earth Return Orbiter — could return the samples to Earth for further study by 2031.
Was Mars ever home to alien life? If so, scientists believe astrobiological evidence may lie in the ancient rocks and soil of the planet's Jezero Crater, where a lake existed 3.5 billion years ago.
Over the next decade, NASA and European space agencies plan to collect samples from the Jezero Crater and return them to Earth. The mission began at 7:50 a.m. EDT on Thursday, July 30, with the launch of NASA's Perseverance rover, which will embark on a seven-month journey to Mars.
The six-wheeled rover is set to descend to the Martian surface in February 2021. It will then start collecting rock and soil samples that could contain biosignatures of ancient microorganisms — a project that the European Space agency likens to an "interplanetary treasure hunt." Perseverance, previously named the Mars 2020 rover, will store its samples in protective tubes, which it will leave behind for a smaller "fetch rover" to pick up on a future mission.
If all goes well, the fetch rover will transport the samples to a craft called the Mars Ascent Vehicle, which will launch a rocket containing the samples (protected inside of a basketball-sized container) into orbit. A satellite will then intercept the container. To do this, the satellite — an Airbus-France spacecraft dubbed Earth Return Orbiter (ERO) — must carefully position itself to catch the container at the right moment.
In 2031, the ERO will return to Earth, where it will drop the container through our atmosphere to a landing site in North America.
Jerezo Crater landing site
Photo: NASA/JPL-Caltech/USGS/University of Arizona via Wikimedia Commons
It would be the first mission to return Martian matter to Earth.
"This is not just twice as difficult as any typical Mars mission; it's twice squared — when you think about the complexity involved," Dr. David Parker, the director of human and robotic exploration at the European Space Agency (ESA), told BBC News.
"And this satellite that Airbus will build - I like to call it 'the first interplanetary cargo ship', because that's what it will be doing. It's designed to carry cargo between Mars and Earth."
ESA's Earth Return Orbiter
Finding signs of alien life isn't the rover's only function. The 2,300-pound Perseverance will be equipped with the Ingenuity Mars Helicopter, a small 4-pound drone designed to help scientists learn more about the feasibility of achieving flight on Mars, a planet with an atmosphere that's 99 percent less dense than Earth's.
Perseverance will also carry technology designed to analyze the chemical composition of the Martian surface, study weather, take images of the Martian subsurface, and produce oxygen from Martian atmospheric carbon dioxide — a proof-of-concept method that could someday allow astronauts to produce oxygen for rocket propellant or breathing.
Illustration of the Mars Ascent Vehicle
But Perseverance's main mission is to find signs of alien life. If it does, that would suggest that life may be relatively common throughout the universe, as Kenneth Farley, the project scientist for Perseverance and a professor at the California Institute of Technology, told The Verge:
"The central question of 'Is there life on other planets?' — it really comes down to: is the origination of life some kind of magic spark that happens only incredibly rarely, or alternatively, is it the kind of thing that is inevitable?" Farley said. "What we can do is we can go to such place in our own solar system on Mars and ask the question, 'Is life ubiquitous?'"
You can watch the Perseverance launch on NASA's YouTube channel at 7:50 a.m. EDT on Thursday, July 30.
We need electric planes, sustainable aviation fuels, and hybrid propulsion now, not later.
In the year when the Swedish word "flygskam" (flight-shaming) hit the news in Europe, public concern about carbon emissions from aviation is endangering the sector's social license to operate.
Aviation is a critical sector that connects travelers and businesses across the globe, fosters economic growth and supports humanitarian missions. It is therefore important for the sector, in collaboration with all those who depend on it, to continue to do all it can to lead the way towards sustainable operations. With demand for flights projected to double over the next 15-20 years, 2019 could be the year that the industry, or at least the most progressive actors within it, define a pathway towards net-zero flying.
Over the last decade, the aviation sector has made progress in improving fuel efficiency through improved aircraft design and operations. The International Civil Aviation Organization (ICAO) achieved an important milestone to limit emissions growth with the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA), a globally agreed market-based measure to achieve carbon-neutral growth for international aviation from 2020.
Alongside these achievements, more options exist when it comes to managing aviation's carbon footprint. While electric planes – which could run at half the cost and noise of conventional aircraft – are a very real medium-term possibility for smaller aircraft on short routes, they're likely not an option for widespread adoption on larger or long-haul flights due to low energy density of current battery technology.
Hybrid propulsion, whereby electric motors would provide initial thrust on take-off and landing for example, could on the other hand reduce emissions in medium- and long-haul flying, but this also will take years to make a substantial impact. This leaves sustainable aviation fuels, or SAF, as the most realistic option today for greener flying. SAF could come in various types of sustainable bio-fuels (derived from waste and not in competition with any food crops) that are in use already today. Synthetic fuels are another potential source, capturing CO2 during their production phase. SAF – which can reduce the carbon footprint of aviation fuel by up to 80% over their full life cycle – started testing on commercial-sized aircraft systems in 2008. As well as being cleaner than kerosene, another benefit of SAF is that they can be blended with conventional jet fuel, allowing for a gradual introduction into supply chains without the need for any expensive engine adaptation.
Air travel is centered around hubs.The fact that the 20 busiest airports in the world handle nearly one-fifth of all air passenger traffic should make it a lot easier for SAF to be adopted en masse by airlines. Yet, seven years after their introduction to commercial flights, they still account for less than 0.1% of total aviation fuel consumption, with airlines struggling to break away from fossil fuels.
SAF will only be in a position to compete effectively with petroleum-based fuels when they can be produced in sufficient quantities. Overcoming this impasse requires a new form of collaboration between different stakeholders across the industry – including airlines, airport operators, aircraft manufacturers, energy companies, financial institutions, government, civil society groups and customers. We believe this is now beginning to change. As it does, there are three instruments that can help drive the process.
1. The "Paris Buyers Club"
One of the most chronic challenges facing sustainability efforts in almost any industry is reaching a consensus among the key players on who bears the inevitable costs. This is usually characterized by a "chicken and egg" scenario whereby producers and consumers are both either unwilling or unable to make the initial investment for new technologies to reach a scale where they are competitive with existing fossil fuel-derived options.
One idea that was discussed at a workshop organized by the World Economic Forum on the side-lines of this year's Paris Air Show suggests this impasse could soon be overcome. Bringing together all the key stakeholders, the suggestion was made that if significant number of large businesses that rely on air travel clubbed together, their collective demand for carbon-neutral travel could catalyse the ramping up of production of SAF. For example, the annual carbon offset budget of one international professional services firm alone could fund up to two new plants for production of SAF. In essence, this would provide in-sector offsets versus out-of-sector offsets such as planting trees, and still earn participating organizations the relevant carbon credits. This idea is not new. Several programmes for redirecting such climate investments currently exist, but there is potential now for forming a larger coalition of corporate actors who want to demonstrate their commitment to climate change and ensure their staff can continue flying at a relatively low cost.
The KLM airplane which runs on biokerose, a type of biofuel.
Lex Lieshout/AFP/Getty Images
2. Finance takes to the skies
Such funding from corporate actors, or a collection of willing enterprises, could also be accumulated in a new type of investment fund, not unlike the Oil and Gas Climate Initiative. Through co-investment, the high risks associated with new refineries and related infrastructure can be lowered, and there can be greater confidence the SAF will be used once produced (referred to as "off-take agreements" in the industry). The more plants that are built, the cheaper the production process and fuel product becomes. The resulting SAF from new refineries may only be used several years after the initial investment, but the capital pooled in the investment fund could provide the initial push necessary to get the industry to 2% (or even higher) use of SAF by 2025. As was shown in the case of solar energy, this would be an important benchmark that raises the prospect for reaching price parity with conventional fuel and achieving a complete energy transition of the industry over the longer term.
Financial institutions could play a direct role themselves. The World Economic Forum's community of CEO Climate Leaders has made great strides in reducing the carbon footprints of their businesses in order to help meet the Paris Climate Goals. Some of the CEOs represent banks that have taken active steps towards ceasing to provide funding for coal-fired power stations and other heavily polluting assets. More recently, stakeholders in the shipping industry have launched the Poseidon Principles, which sees 11 major banks commit to lending portfolios and practices that incentivise the transition to a decarbonised shipping industry. A similar approach in the airline industry could result in beneficial financing terms for operators that commit to progressive adoption of SAF.
If buyers' clubs have the potential to provide significant momentum through a demand-led approach, opportunities exist for supply-led stimulation as well. One option is for airport operators, in collaboration with their carriers, to make landing rights and lowered associated fees an incentive for driving sustainability. Airports faced with the need to expand in order to accommodate growing demand are under huge pressure to limit their environmental footprint or undertake net-zero growth. The beauty of blended biofuels means that airports could gradually ramp up the percentage of SAF provided to airlines, raising it slowly as global supply increases. That percentage could increase to double digits by the 2030s.
In addition, smart regulatory choices designed to make production and sale of SAF more attractive could help level the playing field with traditional petroleum-based fuels. In emerging economies, like India and Brazil, where there is an abundance of appropriate feed stocks, inexpensive solar and wind resources or land available for refineries, such incentives could serve to encourage investment into new supply chains and scale SAF production in the near to medium term.
The well-sequenced combination of nuanced demand- and supply-led innovations, alongside the emergence of new or improved technologies, presents the aviation industry with a much-needed opportunity to protect its social license to operate and grow in an age of increased awareness around carbon emissions. There is no time to lose.