JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD B.Tech IV FLIGHT VECHICLE DESIGN Previous Question Paper (September - 2021 - R16)

To minimize manufacturing costs for a light trainer aircraft, the design should prioritize simplicity and the use of readily available materials. The primary structure should utilize aluminum alloy (2024-T3) or composite sandwich panels with flat-wrap surfaces to reduce complex curvature tooling. A constant-chord, unswept wing design eliminates the need for expensive tapered spar manufacturing and complex jigging. Utilizing off-the-shelf components for avionics, landing gear, and engine mounts significantly reduces R&D and fabrication overhead. Furthermore, implementing a riveted sheet metal construction allows for labor-intensive tasks to be performed by semi-skilled workers, keeping the overall production cost low.

Low maintenance costs are achieved through high accessibility and component reliability. The design should feature large, easily removable cowlings and inspection panels to provide rapid access to the engine, flight control linkages, and electrical systems. A fixed-gear, non-retractable landing gear configuration eliminates the failure-prone hydraulic or electric retraction mechanisms. The use of a certified, air-cooled piston engine with a well-established service network ensures parts availability and simplifies routine inspections. Additionally, employing corrosion-resistant materials and modular avionics racks allows for 'line-replaceable unit' (LRU) maintenance, significantly reducing downtime and labor hours per flight hour.