Yesterday I wrote about Easyjet’s plans to reach zero carbon by 2050, a plan that pegs its hopes to hydrogen aircraft to deliver zero emission flight. While I was critical of Easyjet’s PR approach, there is reason to believe that hydrogen aircraft will be in the air by 2050. Exhibit A in the argument for hydrogen airliners is that it’s already been done.
In fact, it was done in the 1980s.
After the 1970s oil crisis, businesses and governments alike started to think about a future beyond fossil fuels. Smaller and more efficient cars were developed. Solar power and other forms of renewable energy made new strides. Among these various initiatives, the Soviet government directed its engineers to look into post-oil aviation. The task fell to the Tupolev Design Bureau, a pioneering company founded by Andrei Tupolev in 1922.
Tupolev was a genius of aeronautical engineering who would be a household name if he were American. He oversaw the design of over 100 different planes throughout his career, working on both military and civilian planes. He developed his own and also reverse engineered the best designs from other countries on behalf of the Soviet regime. His designs claimed over 70 world records, including the biggest plane in the air in the 1930s. At one point in the 1950s his Tu-104 was the only jet airliner in the world, since its only competitor (the better known De Havilland Comet) was grounded because of safety concerns.
By the 1970s the Tupolev Design Bureau was being run by his son, Alexey Tupolev. He was pretty notable himself as the designer of the Tu-144, which was the first supersonic airliner. It beat the more famous Concorde to supersonic flight by two months – as instructed by the authorities. Unfortunately the nationalist rush to get the record meant the plane was never quite reliable, and it was forced from the skies by high oil prices and a reputation for crashes.
More successful was the Tupolev 154, workhorse of the Soviet civilian fleet, and the plane that used to fly my family to Madagascar in the 90s. It was this reliable mule of a plane that served as a platform for a whole new kind of flight technology – cryogenic aviation.
The back end of the plane was fitted out with a cryogenic pressurised tank that held hydrogen at minus 250C. A plane featured a whole host of innovations to run the experimental engines on hydrogen, including ground operations and filling techniques, not to mention the safety measures needed to fly with pressurised freezing gas on board. But fly it did, making its maiden flight in 1988.
There were two major benefits to hydrogen at the time. The first was that it was an alternative to jet fuel at a time when prices were volatile and supply seemed limited. It could be made from gas, which Russia had in abundance. The second was that it was clean burning. Both were of interest to Soviet engineers, who imagined a pollution-free and ecologically benign form of jet travel.
The experimental Tu-155 made a series of flights on hydrogen, and then it was tweaked to fly on LPG gas, which had only one of the two big benefits. It was cheaper than oil, but sadly not pollution free.
The groundbreaking project led to several other experimental liquid hydrogen and gas planes, including military and space applications. There were a number of breakthroughs in cryogenics, although ultimately the oil price and the environment were not enough to sustain interest in the technology. Plans for a hydrogen airliner and cargo variant, the Tu-156, were dropped. The experimental plane languished in a field and fell apart, before being renovated and displayed at the Gromov Flight Research Institute.
You’d have to ask someone more expert than me to find out how much learning from this project will find its way into a new generation of hydrogen planes. All I know is that has been done. And like renewable energy and electric cars, it was done much earlier than we might expect. If fossil fuels did not have such a grip on our energy system in recent decades, we might have had hydrogen planes in use right now.
The Earthbound Report 