§ Norman BakerTo ask the Secretary of State for Transport what guidance his Department has issued to airlines in respect of flight paths that take commercial aircraft above 30,000 feet. [148589]
§ Mr. McNultyThe Department has not issued any guidance. When designing air traffic services routes, airspace planners are bound by the provisions of guidance material contained in the ICAO Air Traffic Services Planning Manual—Doc. 9426. In addition, the operational approval and aircraft certification given by the Civil Aviation Authority to aircraft operators covers the operation of aircraft at all phases of flight at any level.
§ Norman BakerTo ask the Secretary of State for Transport what environmental assessment has been made of the(a) benefits and (b) disbenefits of commercial aircraft flying at (i) 20,000, (ii) 25,000, (iii) 30,000 and (iv) 35,000 feet. [148590]
§ Mr. McNultyNo specific assessment has been made of the benefits and disbenefits of flight al these altitudes. However, research jointly undertaken by DLR (the German aerospace agency) and Manchester Metropolitan University within the European research project, TRADEOFF, looked at the hypothetical impact of reducing cruise altitudes on contrail coverage and its radiative forcing (a measure of the climate impact), as well as the effect of increased fuel consumption (and hence CO2 emissions). The research concluded that flying at lower cruise altitudes reduced contrail formation but increased fuel consumption.
Any detailed assessment would have to explore these trade-offs further. The research was not intended to suggest changes in operating practices, which would need full international agreement.