because climate matters
Airliner’s fuel efficiency varies with age and usage
The fuel efficiency of airliners depends on the age of the airliner, the length of routes flown and the number of seats occupied.. Continue reading “Airplane fuel efficiency varies greatly and lacks further improvement”
Aircraft wings and the battle for efficiency
1. Wing defines aircraft
Sturdy, short and swept for speed or delicate, long and straight for efficiency? During the past 70 years, the airliner’s wing geometry hasn’t changed much. Advanced materials allow nowadays light-weighted and delicate designs and all current airliners are optimised for high subsonic speeds, e.g. 900 km/h / M 0.85. Why is this so? Continue reading “The Wing”
Aircrafts look the same then 70 years ago
1. Airliner’s fuselages didn’t change for 70 years 
All current aircraft are Tube & Wing designs. A wing, which generates lift, a tube-like fuselage, which holds the load, and a balancing tail. Only small improvements were made to noses, cockpit windows, wing-root fairings and tail-cones. However, these can not improve much further. Continue reading “The Fuselage”
Jet airliner’s engines slow evolution towards fuel efficiency
1. Early jet engines
Above formula shows thrust depending on the mass of air passing through the engine and on the (excess) speed at which this air leaves the engine’s nozzle. Early jet airliners used engines which ejected all air with a very high velocity thought their nozzles. These engines were most effective at speeds close to the speed of sound, e.g. Mach (M) 0,85. Continue reading “The Jet-Engine”
Low prices for fuel and CO2 emissions make airlines focus on fuel-thirsty speeds
1. Airlines always get what they want
Aircrafts are designed around an airline’s business plan. Designers optimise an aircraft’s fuselage, it’s wings and engines to fly with a specific speed to gain an airline the highest profits. The higher it’s speed, the more fuel an aircraft consumes, but the lower are it’s other costs. Continue reading “The price for kerosene defines the airliners that are built”
Aviation needs revolutionary technologies quickly to curb CO2 emissions. However, these get delayed by cheap kerosene
1. International Air Transport Association (IATA), the association of the world’s airlines, sees an urgent need for revolutionary new aircraft designs
„Each new generation of aircraft yields a typical 15% fuel efficiency improvement compared to the generation it replaces. This replacement occurs on average every 20 years, although smaller serial improvements and retrofits occur in the intervening period.”
IATA Technology Roadmap for Environmental Improvement Fact Sheet Continue reading “Revolutionary aircraft technologies are delayed”