Last week, Simple Flying highlighted the advantages and disadvantages that aircraft manufacturers weigh up when selecting single-aisle or dual-aisle fuselage. The fuselage design is essential in determining the shape of the new aircraft, along with the sizing and locations of other major components.
Having to deal with trade-offs between single-aisle or dual-aisle fuselage design, manufacturers must consider airframe mass, airframe drag, and potential turnaround time for the aircraft. Once the design is selected and finalized, it is time for the fuselage development, prototype build, and mass manufacturing.
Development and Prototyping
The fuselage is the main structural component of the aircraft. With many other parts attached to it, the fuselage must withstand the weight of all components and payload, as well as aerodynamic forces during flight. Structural and control elements are simulated using computational software and tested in wind tunnels before manufacturing.
Photo: VDB Photos/Shutterstock.
Design performance is measured to ensure it is within the desired flight constraints and operating parameters. The fuselage prototype is built to establish the manufacturing process and perform tests on the design. A prototype typically goes through a series of structural strength tests before being finalized for mass manufacturing.
In the past, aluminum sheets were used to build commercial aircraft fuselages. The manufacturing processes started with flat sheets of aluminum that were rolled and chemically milled. The fuselage barrel was drilled and riveted to longitudinal and circumferential stiffening parts. Stiffening panels were riveted at various locations along the length and circumference to enhance the strength of the structure. With the advancement in material technology, design and cost issues with the aluminum design started to surface.
The recurring cost and time to build the fuselage were very high. One reason was that much of the process could not be automated. Moreover, the aluminum structure is more prone to fatigue and corrosion. As such, the time and cost of maintenance became significantly high for the operators. The heavy weight of an aluminum airframe determined the aircraft’s range and capability to carry a payload.
Over the course of the last two decades, aircraft manufacturers have been analyzing newer, more-efficient technologies for manufacturing the fuselage. Fiber-metal laminates and graphite-based composites have shown extraordinary strength and lighter weight compared to aluminum airframes. Fiber composites are much lighter, less prone to wear and corrosion, and do not have fatigue problems.
A significant advantage of composite materials is the possibility of producing large cured structures on automated machines. Complete fuselage barrels (longitudinal sections) can be manufactured with minimal time, labor, and cost. One Piece Barrel Technology uses very high automation levels to produce large quantities of fuselage barrels with stable quality and high production rates.
New technology has resulted in fewer joints, fewer pieces, fewer fasteners, and a lower overall weight. Moreover, the assembly time is significantly reduced due to the reduction in overall workflow. As a result, aircraft operators can minimize their operational (fuel per unit of payload) and maintenance (wear) costs.
What are your thoughts on fuselage development and manufacturing? Tell us in the comments section.