Working towards the ideal laminar flow structure

Airlines and aircraft manufacturers are forecasting significant incerases in passenger traffic over the next 20 years (1), (2) but it is becoming increasingly apparent that, given a future scenario of increasing fuel costs and environmental controls, this is unlikely to be sustainable unless aircraft become more efficient and environmentally friendly than those in service today.Hybrid Laminar Flow (HLF) offers a significant contribution towards any overall efficiency improvement but requires relatively complex structures and systems leading to increases in weight, cost and maintenance. Since HLF has never been applied on a production basis, no mature manufacturing solution has evolved for the associated structure or systems. This paper reviews the requirements for HLF strutures and the progress made towards production solutions. It also recognises that the optimum structure may be influenced by the relative importance of fuel saving (or emissions reduction) compared with operating cost reductions.