composite mass in 20% of structural mass A320 A340 A310/300 10% A300/600 A A concorde300310 vautour 6% (3.3 tons) 1970 1980 1990 Figure 7.2 Evolution of Mass of Composites in Aircraft composite in of aerodynamic 767 surface 30% 747 757 0 20% 737 10% 727 0 707 0 1960 1970 1980 1990 Figure 7.3 Use of Composite in Boeing Aircraft How to evaluate the gains: In theory:For example,a study was made by Lockheed Company (USA)for the design of a large carrier having the following principal characteristics:payload 68 tons,range 8300 km.This study gives the following significant results: for an aircraft made using conventional metallic construction: total mass at take-off:363 tons mass of the structure:175 tons ■for an aircraft made using“maximum”composite construction: total mass at take-off:245 tons mass of the structure:96 tons. Such a difference can be explained by the cascading consequences that can be illustrated as in Figure 7.4. In practice:In reality,introduction of composites in the aircrafts is limited to certain parts of the structures.It is done case by case and in a progressive manner during the life of the aircraft (re-evaluation operation).One is then led to consider the different notions: 2003 by CRC Press LLCHow to evaluate the gains: In theory: For example, a study was made by Lockheed Company (USA) for the design of a large carrier having the following principal characteristics: payload 68 tons, range 8300 km. This study gives the following significant results:
for an aircraft made using conventional metallic construction: total mass at take-off: 363 tons mass of the structure: 175 tons
for an aircraft made using “maximum” composite construction: total mass at take-off: 245 tons mass of the structure: 96 tons. Such a difference can be explained by the cascading consequences that can be illustrated as in Figure 7.4. In practice: In reality, introduction of composites in the aircrafts is limited to certain parts of the structures. It is done case by case and in a progressive manner during the life of the aircraft (re-evaluation operation). One is then led to consider the different notions: Figure 7.2 Evolution of Mass of Composites in Aircraft Figure 7.3 Use of Composite in Boeing Aircraft TX846_Frame_C07 Page 140 Monday, November 18, 2002 12:17 PM © 2003 by CRC Press LLC