5 of 16
Fin Mounting:
The High Aspect Ratio Fin uses a custom non-symmetrical hydrofoil section. This fin has
a top and a bottom as defined in
Figure 2
which shows an end profile of the fin’s cross
section. The top of the fin can be identified by its completely convex shape, while the
bottom is partially concave.
FIG 2
When properly assembled, the fin mounts to the Exo-Skeletal Frame with the fin’s leading
edge and top facing pointed back end of the fairing top and the bottom of the fin against
the suspension straps as shown in
Figure 3
. An improperly mounted fin will severely
decrease fin performance.
Suspension Straps:
The Suspension Straps are made of an elastomer & nylon composite material configured to
give the fin suspension a non-linear response. To achieve this characteristic, the nylon
laminations are offset from the centerline of the Suspension Strap. This offset is visible by
looking at the side edge of a Suspension Strap. To properly mount the Suspension Straps
to the Orca Bracket, the nylon laminations should be offset away from the Mounting Tabs
on the bracket and close to the fin as depicted in
Figure 3
. Mounting the Suspension
Straps upside-down will affect the fin’s angle-of-attack control and thus affect the overall
performance of the DOL-Fin.
6 of 16
Hardware:
Eight screws (of which 4 come pre-assembled) fasten a sandwich of components together
to form the DOL-Fin’s hydrofoil suspension system. Do not over tighten these screws.
Over tightening will compress the suspension straps and can cause misalignment of the
trim plates or can damage the PE Twin Screw Washer Plates. These screw/nut sets should
be tightened lightly. The proper assembly of the suspension system components set up
mounted through the forward mounting holes in the Orca bracket can be seen in
Figure 3
.
FIG 3
