Average Diameter, Dave
For a noncircular cross-section, this is the average of the fuselage height and width at the constant cross-section barrel part (Dave = (H + W)/2). Sometimes this is defined as Deffective = V(H*W); another suitable definition is Dequivalent = perimeter/2^. This book uses the first definition.
3.23.12 Cabin Height, Hcab
This is the internal cabin height from the floor, as shown in Figure 3.50.
3.23.13 Cabin Width, Wcab
This is a the internal cabin width, as shown in Figure 3.50.
3.23.14 Pilot Cockpit/Flight Deck
This is a term used for the enclosed space for the flight crew in the front fuselage. Chapter 15 describes the flight deck in more detail.
A military aircraft fuselage is very different because it does not have passengers to carry and is more densely packed. Various types of fuselage cross-sections are shown in Figure 4.7 (see Web site). Their associated fineness ratios and other statistical data on fuselage parameters are provided in Section 4.7.