Back in 2021, the Department of Transportation set in motion a plan for the US aviation sector to achieve net-zero emissions by 2050. NASA, the government’s go to for civilian aviation research, discussed its advancements, challenges, and predictions on hybrid/electric aircraft at EAA Oshkosh this week.
NASA is playing the role as early researcher in the DoT’s goal, looking at various ways to increase aircraft efficiencies. One well know area are sustainable aviation fuel (SAF). SAFs hope to play a big role in early drops in emissions as it can be mixed in with regular kerosine based fuel.
However, SAFs won’t get us all the way there, pushing what is possible in the core of the engine might just be the next step in lowering emissions from the largest emitters in the world.
So from a sustainability standpoint, it’s not can we reduce [emissions] from where we are today, it’s where we’re gonna be projected in flying in 2035. So you have to start doing hard stuff today.
Mark Turner – Senior Technologies, Aeropropulsion Propulsion Division, NASA
NASA’s Hybrid Thermally Efficient Core (HyTEC) is one of those programs you probably won’t ever hear about unless you sho up at a trade show. The work is not something that will likely make is way down to the general aviation sector but stay with large, commercial airliner jets that need every percent they can get of fuel efficiency.
Touching several hot points inside the engines used by Boeing and Airbus aircraft, the program would like to see a 5 to 10% efficiency in fuel burn over current engines. The program could also create smaller engines, a gateway to hybrid engines, and increased power extraction.
They’re doing this by looking into the core of the engine, primarily the high and low pressure turbines and shafts that turn them. Being able to develop new materials that withstand higher heats can be key to making the engines smaller, which can bring efficiencies.
One exciting idea is to experiment with added some sort of hybrid battery technology that stores energy from the turning shafts inside the engine. This would mean two things, having the power for later stages of flight or transferring power between high and low turbine shafts.
While hybrid and fully electric aircraft might be a ways away, HyTEC can be seen as a early step in making the 2050 net-zero emissions goal a reality.
Push back from EAA attendees
It wasn’t all sunshine and roses when discussing the projects during a public forum. Many thought the relatively low efficiency boosts weren’t worth it or that the aviation sector has already peaked with how much more efficient the engines can get.
However, at scale, even just a 5% boost would mean hundreds of thousands of gallons of fuel not burned, which means less carbon emissions released into the atmosphere. As mentioned before, HyTEC is working on changes to engines used on the large Boeing or Airbus aircraft we fly across the country in, not small general aviation aircraft like Cirrus or Cessna.
Actually, during the forum at Oshkosh, NASA researchers mentioned that smaller general aviation aircrafts might be a better fit for moving directly into hybrid electric power systems than what HyTEC is working on.
There are also other plans in place to secure more efficiencies else where. New wings, further engine designs, battery technology, and of course fuels, will all play a role in lowering emissions over the next few decades.
