enough to avoid instabilities like, divergence, aileron reversal and flutter. (III) Layout peculiarities The specific function of the airplane often decides its shape e.g. the fuselage of a cargo airplane generally has a rectangular cross section and a large cargo door. The height of fuselage floor should be appropriate for quick loading and unloading
SUKUMAR.D -AP/SOA Page 12 (IV) Manufacturing processes During the detail design stage, attention must be paid to the manufacturing processes. The cost of manufacture and quality control also must be kept in mind. (V) Cost and operational economics – Direct operating cost (DOC) and Indirect operating cost (IOC) The total operating cost of an airplane is the sum of the direct operating cost (DOC) and the indirect operating cost (IOC). The DOC relates to the cost of hourly operation of the airplane viz. cost of fuel, lubricants, maintenance, overhaul, replacement of parts for airframe and engine. IOC relates to crew cost, insurance cost, depreciation of airplane and ground equipment, hangar rental, landing charges and overheads. Thus, for a personal plane lower initial cost of the airplane may be more important whereas, for a long range passenger airplane lower cost of fuel may be the primary consideration. (VI) Interaction of various factors Some of the considerations mentioned above may lead to conflicting requirements. For example, a wing with an airfoil of relatively higher thickness ratio, has lower structural weight but, at the same time has higher drag. In such situations, optimization techniques are employed to arrive at the best compromise. Primary requirements for Civil Aircraft Passenger Aircraft High Safety level High payload carrying capacity Economy in operation Comforts Ability to fly in any Weather (All-weather flying) aerodromes Ability to use aerodromes of respective classes Cargo Aircraft High payload carrying capacity Economy in operation Ability to fly in any Weather Suitable for civil aerodromes Primary requirements for Military Aircraft Strategic Long range (over 6000 km) High load carrying capacity - (2000-4000 kg) High speed High endurance High ceiling Adequate fire protection Tactical Long range 3000-5000 km) High load carrying capacity (above 6000 kg) High speed High ceiling
SUKUMAR.D -AP/SOA Page 13 High endurance All-weather flying Ability to use field aerodromes Primary requirements for Military Aircraft – FIGHTERS-Tactical High speed (300-400 kmph- more than contemporary bomber speeds) High ceiling (2-4 km than bomber more than contemporary bomber ceilings) Maneuverability Sufficient endurance High rate of climb Ability to launch repeat- ed attacks All-weather flying Ability to use field aerodromes Ease of dismantling and assembling Primary requirements for Military Aircraft – FIGHTERS- Interceptor High rate of climb High ceiling (3-4 km contemporary ceilings) High speed (500-600 kmph more than contemporary bomber speeds High Maneuverability All-weather flying Ability to fire powerful single volley at target Ease of dismantling and assembling
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- Spring '14
- Aerodynamics, Wing design, Aircraft Design, V-n diagram, Military aircraft