Tham khảo tài liệu 'thiết kế kỹ thuật máy bay chiến đấu episode 3 part 3', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 520 THE DESIGN OF THE AEROPLANE Wo Kg Soo ÍOOO 2ooo Sooo íỉroSS We ig kfc _d i s l Kce lAAiK-t v o looolb Fig. Float weight. or supported outside them on pylons. When an engine is buried within a structure it is often more sensible to treat the weight of its mounting as structure weight rather than as powerplant weight. Thus some juggling may be necessary. This does not matter as long as we are consistent. Table 14-11 summarises some of the weight ratios of nacelles and pylons. When an engine mounting is counted as structure weight its weight must be subtracted from the powerplant weight . about to Wo must be taken away from the powerplant weight ratio. Stabiliser and tail unit We include under this heading the weight of the tailplane or a canard foreplane together with elevators fin rudder and tabs of various kinds. Typically the total weight of the stabilising control and trimming surfaces is 2 to 4 per cent of the gross weight. Further the weight of these items can be treated as a fraction of the wing weight because it is affected by similar factors. HOW BIG AND HOW HEAVY 521 Table 14-11 Nacelle Weight Estimation Nacelle. ArraageCvie -t OtAer Estinaatres SiiaaN - fairiag 0015 2 to 3 ib ft1 to to 15 K oa 1 based uf ou Surface. aria Fuel FaaK for r - - -fain-iv Wkeuc for xS alloy fuel Faak. slciw z i-jei lb is Couglaly u-u uteri aoJIy bo capac ity Ila I iA .f eria_ galloixS 2 bubseeajso Fo-ble 14-15 . Nacelle 1- eiA ine PxouiAtiiag o o I 4-lU f A I AS Kg iaa1 based of oia Surface car e_a. for i ouuiiAọ IN I lag y Io la to far Ểiagiiae. About X f oiojer aiat lol ei y la-h Fuselage fjyloia 0 005 bo fjer eia fiiae. About oxe lacxif tlae Value gix eia above. Estimations of the weight of the whole tail unit and its parts can be made from fig. and table 11-4. The first shows the tail unit weight as a ratio of the weight unit area of the tail to the weight unit area of a
