Empennage Area versus Wing Area
Once the wing area is established along with fuselage length and matched engine size, the empennage areas (i. e., H-tail, SH, and V-tail, SV) can be estimated from the static stability requirements. Section 3.22 discusses the empennage tail-volume coefficients to determine empennage areas.
Figure 4.10 shows growth for H-tail and V-tail surface areas with the MTOM. The variants in the families do not show change in empennage areas to maintain component commonality.
Figure 4.11. Wing span versus wing-loading and aspect ratio 4.5.7 Wing Loading versus Aircraft Span
Figure 4.11 substantiates Equation 3.43 in Section 3.20.1, which states that the growth of the wing span is associated with the growth in wing loading.
With steady improvements in new-material properties, miniaturization of equipment, and better fuel economy, wing span is increasing with the introduction of bigger aircraft (e. g., Airbus 380). Growth in size results in a wing root thickness large enough to encompass the fuselage depth when a BWB configuration becomes an attractive proposition for large-capacity aircraft. Although technically feasible, it awaits market readiness, especially from the ground-handling perspective at airports.
The aspect ratio shows a scattering trend. In the same wing-span class, the aspect ratio could be increased with advanced technology but it is restricted by the increase in wing load. Current technology provides for an aspect ratio from 8 to 14.