Editing Biplane (section)

=== Bays ===
The space enclosed by a set of [[interplane strut]]s is called a ''bay'' (much as [[Bay (architecture)|the architectural form]] is used), hence a biplane or [[triplane]] with one set of such struts connecting the wings on each side of the aircraft is a ''single-bay biplane''. This provided sufficient strength for smaller aircraft such as the [[First World War]]-era [[Fokker D.VII]] fighter and the [[Second World War]] [[de Havilland Tiger Moth]] basic trainer.<ref name = "jackson 3 4">Jackson 1966, pp. 3–4.</ref>

The larger two-seat [[Curtiss JN-4]] Jenny is a ''two bay biplane'', the extra bay being necessary as overlong bays are prone to flexing and can fail. The [[SPAD S.XIII]] fighter, while appearing to be a two bay biplane, has only one bay, but has the midpoints of the rigging braced with additional struts; however, these are not structurally contiguous from top to bottom wing.<ref name="profile p6-7">Andrews 1965, pp. 6–7.</ref> The [[Sopwith 1½ Strutter]] has a W shape cabane, however as it does not connect the wings to each other, it does not add to the number of bays.<ref name="bomber-40">Lake 2002, p. 40.</ref>

Large transport and [[Bomber|bombing]] biplanes often needed still more bays to provide sufficient strength. These are often referred to as ''multi-bay biplanes''. A small number of biplanes, such as the [[Zeppelin-Lindau D.I]] have no interplane struts and are referred to as being ''strutless''.<ref name=G0>Grosz 1998, p. 0.</ref>
<gallery>
File:Zeppelin-Lindau (Do) D.I.jpg|[[Zeppelin-Lindau D.I]] strutless biplane
File:Nieuport 23 C.1 (colour).jpg|[[Nieuport 23]] single-bay sesquiplane
File:SPAD S.XIII Front.jpg|[[SPAD S.XIII]] single-bay biplane with auxiliary struts
File:Fearless Freddie, stuntman cph.3b18313.jpg|[[Curtiss JN-4]] two-bay biplane
File:Handley Page V-1500.jpg|[[Handley Page V/1500]] four-bay or multi-bay biplane
</gallery>