Fast Motor Boat Wreck, 21-HE-560, Lake Minnetonka
Underwater Archaeology, Maritime Heritage Minnesota, Not For Profit
The Fast Motor Boat Wreck, 21-HE-560, burned to the waterline just above the splashrail in the stern and at the turn of the bilge forward, with the exception of the transom and the stempost. From the stempost to the transom, the wreck is 30.40 feet long, she is 6.00 feet in the beam, and has a 5.80-foot wide transom. The stempost survives in its entirety, with a metal strip and small bow casting attached to the wooden post with slot-head woodscrews. The casting is triangular with one rounded side, and a metal strap and loop is attached to the inner stempost below it. MHM contends the loop might have been part of a forward internal truss system to prevent hogging. On both the port and starboard side of the stempost, small sections of slat strakes survive with white caulking between them. The stempost rises out of the bottom silt, and the bottom hull section in front of the engine is covered - it does survive, however. Amidships, the port hull just at the turn of the bilge can be discerned, but moving aft, both sides of hull have surviving strakes, frames, and floors. The topmost sections of the strakes and frames show thorough burning and checking on both port and starboard quarters; the starboard side shows less burning than the port side. On both quarters, a substantial splashrail survives and extends around to the transom on both sides; this splashrail type has not been seen on any known Minnesota wreck identified to date. The transom is nearly intact, with just the amidships gunwale and port side upper strakes damaged; it is comprised of 3 large planks, with the widest example in the center. The 4-cylinder engine is amidships, attached to a large 'H' or 'ladder'-shaped mount that is secured to the wreck's bottom. The engine is very corroded, but several attributes are identifiable including the cylinder head, flywheel, driveshaft, clutch, clutch lever, cooling water manifold, cooling water intake and discharge pipes, an unattached carburetor, starter motor, battery cable, crankshaft sprocket and chain, electric starter, manual crank starter bracket, drive shaft, oil pump, and a capless distributor. To port, the steering mechanism is attached to the hull bottom stringers and the steering column extends aft into the water column. A partial steering wheel survives, and the remains indicate that the wheel is the 'aviator' type, a style sometimes used on early race boats. The engine mount - reminiscent of a set of stringers - extends nearly to the stern, stopping at the remains of an athwartships bulwark that signals the beginning of the rear deck area. Between the engine mount 'stringers', the propellor shaft is seen running from the rear end of the engine - with couplings visible; it disappears into the silt and into a conduit through the bottom of the vessel. To port, a metal battery platform survives but the battery did not. Behind surviving athwartships bulwark remnant toward the stern, the metal stern gear of the Fast Motor Boat Wreck survives, including a long muffler lying athwartships. Two exhaust pipes leave the muffler on both ends that are guided through the inner transom by 2 round flanged plates that act as stabilizers. Another 2 round flanged plates on the outer transom serve the same purpose. Above the starboard side flanged plate, a round metal screen is affixed over the round hole in the transom, allowing for air flow; the port side example is missing along with the wood that held it in place. Between the muffler and the transom, the rudder post protrudes through the bottom of the hull, ending in a cable drum that would have had the steering cables wrapped around it, controlled by the steering wheel further forward. Behind the rudder post, an amidships wooden knee is affixed to the inner transom and the hull bottom. Even with a fragmented nature of the wreck, it can be determined that the hull had significant tumblehome from the quarters to the transom.
MHM has determined 21-HE-560 was constructed around 1905 due to the probable design of the vessel, and the presence of a hand crank apparatus attached to the forward end of the engine. At some point during the working life of the Fast Motor Boat Wreck, she was converted from manual crank to an electric start. MHM contends the Fast Motor Boat Wreck's gas tank, located at the bow, exploded and blew the much of the bow compartment apart, while the hull amidships and aft caught fire. From the burning pattern, it is apparent that the forward section of the hull - after bearing the brunt of the explosion - burned to the waterline. Amidships, the hull burned to the waterline and aft, the hull stopped burning above the splashrail, and the transom is nearly intact - while the aft deck and the top of the transom burned. MHM asserts that transom, that is significantly scorched on its inner surface, survived nearly intact because it is thicker than other strakes and it was the first portion of the vessel to sink. The stern area had the weight of the muffler and rudder gear, along with the amidships weight of the engine and its associated equipment. The wreck sank stern first and the water extinguished the fire on both quarters, allowing more strakes and the splashrail to survive. The area fore of the engine was above the water longer, and therefore burned to the waterline and even slightly below the waterline at the bow. The thickness of the stempost and its metal sheath, combined with the bow strakes attached on both sides created a thick mass that did not burn before the wreck sank. MHM has located a number of historical references to watercraft explosions on Lake Minnetonka in the early 20th Century. To date, none of these reports have sufficient details for MHM to determine that they are referring to the Fast Motor Boat Wreck. MHM is confident the wreck sank between 1920 and 1935 based on the age of the vessel, assuming construction around 1905, and the amount of silt in the hull bottom. Water flows through the wreck site quickly and most of the silt in the water column remains in suspension, not being deposited on the wreck. Other nearby sites of a similar age (Ramaley Family Motor Boat Wreck [21-HE-490], Wooden Trunk Cabin Cruiser Wreck [21-HE-446]) are in similar conditions with little silt build-up.