Figure 371
Fig. 371
normal (571x430, 10 KB) large (1024x772, 20 KB) EPS (2 KB)
Trend in overall efficiency of propulsion h (solid circles), computed from aircraft specific fuel consumption (SFC) data (open circles; data as in Chapter 7, adapted from Aylesworth, 1997), according to h = V(Q SFC)-1, with V as the aircraft speed (about 240 m s-1) and Q as the specific heat of combustion aviation fuels (43 MJ kg-1). The solid circles also denote the critical altitude z (right axis) above which contrails form (for 100% relative humidity in the mid-latitude standard atmosphere) for the years 1960 to 2010.