D.H. 86 "Express Air Liner" (British) : a four-engine biplane (1934)
NASA Technical Reports Server (NTRS) · leaf 10
N.A.C.A. Aircraft Oiroular No. 189 Figs. 5,6,7,8 Figure 6.-These diagrams il- lustrate the oper ation of the fin euid stabi- lizer adjustment and rudder balance.
NASA Technical Reports Server (NTRS)
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