When I first observed the boat lift (as illustrated above), I was a bit confused about how it operated. I deduced that the moving portion was the entire planked deck area. The boat's keel rests directly on the deck, and the four posts constrain the boat to the very center of the deck, as well as acting to limit the amount of heel on the boat once it is raised from the water. The lowering mechanism is not seen in the view shown, but I presume it must be electrically operated.
Several aspects of this design are worth some discussion:
- having the boat supported on a fully-planked deck makes access to the boat for boarding or for working on the boat to be very easy;
- the deck planking must not be wood, as the buoyancy of the deck would become a problem once the boat was floated off, or if the decking is wood, there must be a very considerable weight in steel beams involved in the moving part of the lift;
- the keel of the boat bears the entire weight of the boat, which for a Boston Whaler Unibond hull is the best possible configuration;
- the lifting mechanism appears to be hidden below the two outer (white) beams of the lift structure, but the gear is high enough to be completely out of the water when the boat is raised; and,
- access to the lift deck is flush with the dock finger pier, making for very easy boarding; note the apparently fixed boarding step fastened to the deck on the left to aid in getting aboard the boat from the lift deck height.
The boat shown in Figure 1 is a fire-boat, with a red fire monitor pump in the bow (partially seen). It may also be used as a rescue boat. The hull is the classic OUTRAGE 25. The bow stem and forward v-hull are seen very nicely in this unusual view, demonstrating the classic Bob Dougherty hull design. This boat has a steel keel guard installed. I could not see if it continues for the entire length of the keel, but it very well could. Such a long keel guard would be appropriate for use with this lift, and it would also protect the hull if the boat were to be grounded in the shallow waters near shore in the Tampa Bay area.
One drawback to this design: it is supported by six or more large wooden [pilings], and it is thus a rather permanent installation. In my boating area, north of latitude 45-degrees, most boat lifts are removed by October to prevent damage from winter ice. A design similar to the one shown above might be possible if located in a sheltered area along the shore protected from large ice flows from the open water of Lake Michigan.