Reducing aircraft fuel costs & emissions

The level of drag experienced by commercial transport aircraft directly impacts performance, cost and the environment.

Increasing fuel efficiency is essential to cutting airline operating costs and reducing CO2 emissions to uphold agreed global aviation targets.

Currently, one third of airline operating costs are spent on fuel and whilst the aviation sector is committed to reducing its global aviation emissions to 50% of 2005 levels by 2050, current forecasts suggest that they may in fact grow by 300-700%.

IATA Airline Operation Cost Task Force

Proportions are approximate

0 Others Pax Service Distribution Charges Maintenance A/C Ownership Cost of Operations Fuel 5 10 15 20 25 30 35 40 %

Emissions Statistics

Illustration of aircraft emitting cloud of CO2 behind it
359m tonnes CO2 emitted by Worldwide flights in 2017: a similar amount as the UK’s total net emissions.
Illustration of cloud with Co2 written in it
2% of all human induced CO2 emissions are produced by the global aviation industry.
Illustration of 2050 with arrow below
50% reduction in global aviation net carbon emissions from what they were in 2005.

Source: Air Transport Action Group (ATAG) – 2017 UK Greenhouse Gas Emissions Provisional Figures

Whilst the adoption of the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) aims to stabilise emissions with carbon offsetting, improving fuel efficiency is crucial to achieving the 2050 goal.

Approaching Drag

Developments of the jet engine have predominantly driven aircraft efficiency, but aerodynamic innovation is needed if we are to continue to reduce fuel costs and emissions.

Skin friction drag accounts for approximately 50% total drag of a typical long-range aircraft at cruise conditions.

A 1% drag reduction accounts for 1.6 tons on the operating empty weight or 10 passengers*.

The increase or decrease of drag centres around the ability to delay the transition of laminar airflow to turbulent airflow as it flows over the aircraft surface.

Under the same condition, a laminar boundary layer across the aircraft surface could reduce skin friction to 20% that of a turbulent boundary layer. This also produces an equivalent reduction in overall drag and corresponding fuel consumption.

*Overview on drag reduction technologies for civil transport aircraft (Reneaux, J. 2004, p.2)

Turbulent Flow v Laminar Flow

Free moving air Surface Edge of boundary layer
Free moving air Surface Edge of boundary layer 0.02in

Its elimination would reduce the power required to propel an aircraft, decreasing fuel consumption, cutting costs and reducing emissions to address CO2 targets. It could also increase an aircraft’s capable load and allow it to travel further.

CAV’s Hybrid Laminar Flow Control Technology

Traditionally, laminar flow has been enhanced by optimising the design of airfoils and fuselage geometry.

CAV’s development of hybrid laminar flow control (HLFC) technology µLASE actively delays the transition of laminar to turbulent flow. Using a perforated skin applied to the first part of the aircraft chord, µLASE pulls turbulent air away from the boundary layer, reducing drag and significantly enhancing fuel efficiency.