Aircraft

Airbus Helicopters flight tests kerosene-fueled lightweight V8 piston engine

Airbus Helicopters flight test...
The new engine made its first flight in an H120 helicopter
The new engine made its first flight in an H120 helicopter
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The new engine made its first flight in an H120 helicopter
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The new engine made its first flight in an H120 helicopter
The new engine made its first flight in an H120 helicopter
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The new engine made its first flight in an H120 helicopter

Most piston-driven helicopters use aviation-grade gasoline or avgas, but as part of the European Clean Sky initiative, Airbus Helicopters has begun flight testing of a new high-compression engine that burns widely-available kerosene aviation fuel. Installed in an H120 demonstrator aircraft, the advanced lightweight V8 piston engine promises to be a more efficient, cleaner alternative to turbine powerplants in high-performance rotorcraft.

According to Airbus Helicopters, the new 4.6-liter, V8 high-compression piston engine demonstrates a wide variety of advanced features and technologies. With one turbocharger per cylinder bank, the engine achieves pressures of 1800 bar and has common-rail direct injection. It has fully-machined aluminum blocks, titanium connecting rods, steel pistons and liners, and for the motor oil it uses liquid-cooling and a dry sump management system similar to that used on aerobatic aircraft and race cars.

The engine has been under development since 2011 and ground tests of the H120-equipped helicopter were conducted in February and March 2015. Its maiden flight took place on November 6 at about 3 pm at Marignane Airport, France. Airbus Helicopters says that future tests will work on determining the optimum power-to-weight ratios, confirming the engine's emission standards, and making it competitive with turbine power plants.

"The first result of the 30 minutes flight confirms the advantages of new-technology high-compression piston engines for rotorcraft in offering reduced emissions; up to 50 percent lower fuel consumption depending on duty cycle, nearly doubled range and enhanced operations in hot and high conditions," says Tomasz Krysinski, Head of Research and Innovation at Airbus Helicopters.

The kerosene-burning engine is being developed by Airbus Helicopter as part of the European Clean Sky initiative's Green Rotorcraft Integrated Technology Demonstrator (ITD) program which aims to produce greener, quieter, more efficient aircraft engines. The goal is to eventually cut down fuel consumption by 30 percent, CO2 emissions by 40 percent, and NOx by 53 percent.

Source: Airbus Helicopters

7 comments
Sonofdawn
Pity they didn't opt to use a Wankel motor, they're ideal in aeronautical applications.
mhpr262
50% lower fuel consumption? wow. That is a weighty argument in favour of that new engine.
Wombat56
" the engine achieves pressures of 1800 bar and has common-rail direct injection.".

Yeah, I suspect that figure applies just to the pressure in the common rail fuel injection part, not in the engine proper.

If they've designed a piston engine to run with cylinder pressure of nearly 1800 atmospheres or around 25,000 PSI that really WOULD be impressive, but the Airbus article itself is a little unclear.
Expanded Viewpoint
Well good luck on bringing those NOx numbers down with such a high compression ratio, unless EGR is used, which can cut engine efficiency down. So that then means more fuel will need to be burned. What the heck does the engine oil have to do with liquid cooling, unless the oil is being run through a radiator to get rid of the heat from friction and combustion?
Randy
Martin Hone
"and for the motor oil it uses liquid-cooling and a dry sump management system similar to that used on aerobatic aircraft and race cars." ????
And the name for aviation kerosene is Avtur.....
MQ
So this engine must have a 2 stage heat exchanger, oil to (water based) coolant and then coolant to air heat exchanger (if the liquid cooling is correct.
The reason the oil is mentioned is probably that in piston engine aircraft typically oil is circulated as the coolant, and engine temp is measured by the oil temp.
Piston engines, while historically much less energy dense than turbines, are generally much more fuel efficient at partial "throttle" settings, Maybe: times, they are a-changing?