212 G. J. Wennagel 
STRAIGHT LINE 
ELEMENTS 
ELLIPTICAL NOSE 
T, 
0.035c— 
pl et oye set | 3 
TAIL FOIL SECTION 
ALL INTERSECTIONS OF STRAIGHT LINE ELEMENTS ARE ROUNDED 
0.032 aa 
LOCATION C IN. 
ROOT 13.00 T=0.0375C 
OUTBOARD TIP 3.66 T,=0.0254C 
PARABOLA 
TAIL STRUT SECTION 
Fig. 6. Cross sections of the tail strut and hydrofoil 
insertion from the upper side of each diagonal and with tapped holes in each cruise foil 
element. These intersections are thus maintained hydrodynamically clean without resort to 
bodies of revolution. Diagonal to upper strut connection on each forward foil assembly 
involves one fitting and connecting bolts. Each of the two lower struts extends up into an 
adjoining, hollow, upper strut; attaching bolts connect the mating segments. This design 
enables easy replacement or modification of any of the four, separate components which 
make up each forward hydrofoil assembly. 
The propeller pod is split along a horizontal plane so as to form an upper half and a 
lower half. Suitable machining allows for the insertion of a one-piece tail foil between the 
upper and lower halves of the pod. Attaching bolts, which are externally flush, connect 
these three structural elements. Thus, emphasis has been placed on obtaining a design 
which allows easy replacement or modification of the tail hydrofoil. 
A welded connection is employed between the upper half of the pod and the tail strut. 
This welding extends around the entire perimeter of the strut cross section and has been 
hand polished to obtain a smooth finish. Rigid and fixed connection between these two 
elements was a design requirement so as to allow subsequent, internal machining of both 
strut and pod in a manner that could guarantee proper alignment of transmission components. 
An upper tail strut, of hollow construction, attaches to the top of the lower strut, and 
provides support at its upper end for a right-angle gear box. Gear box and lower strut 
attachment is by bolts to allow easy disassembly and inspection of internal transmission 
components. 
