Marine Exchange of Alaska

The Marine Exchange has been watching the little steam launch LAURIE ELLEN making her rounds in Juneau Harbor for a couple of years, but we never had the time to get onboard. Finally on May 4, 2007, we noticed the boat at her moorings at the City of Juneau Department of Public Works below the bridge to Douglas. As Special Projects Manager for the Marine Exchange, I'd met the operator earlier at a Coast Guard seminar on small passenger vessel operations. Both of us, in previous lives, had operated much larger steam powered ships. He began describing the LAURIE ELLEN's unique little steam engine and boiler to me. The more he talked the more intrigued I became. I had to see this rig for myself.

LAURIE ELLEN's motive power comes from her wood burning single pass fire tube boiler shown here that supplies saturated steam to the engine at a pressure that varies between 80 and 140 pounds of pressure to the square inch. A feed pump driven off the main engine takes suction on a feed tank aft of the boiler to keep the boiler fully supplied with fresh water. At the beginning of the season the boiler is filled with city water, however, a feature of the boat's canopy allows rain water to be trapped and used for boiler feed as the rain water is much more pure than even the City of Juneau water. Here you can see the boiler water gage glass and try cocks that allow the operator to keep assured that he is maintaining the proper water level in the boiler. The boiler pressure gage is visible and the main steam stop valve allows steam to exit via the insulation wrapped main steam line leading to the engine.

Here is the LAURIE ELLEN's main engine. The steam enters the high pressure cylinder controlled by the wooden handled throttle valve. The piston inside of the first cylinder is double acting, that is to say that steam pressure acts on both sides of it to cause it to rotate the crankshaft. A D type slide valve controlled by an eccentric off the main crank shaft operates to control and reverse steam flow to the piston at the proper point in its stroke. Exhaust steam from the first cylinder is directed over to the second cylinder by the crossover pipe. The second piston is also double acting also controlled by a D type slide valve also operated by a valve rod coming from an eccentric on the main shaft. After the steam runs through both cylinders it is exhausted to the keel cooler outside the hull of the boat. The steam is condensed in the keel cooler and returned to the feed tank where it is cycled back to the boiler by the feed pump. The wooden coverings on the two cylinders and the crossover pipe were added after the boat had entered service and have served to conserve the heat energy in the steam and have actually reduced the amount of wood necessary to be burned. Although the engine uses saturated (wet) steam, it must be lubricated and special oils are used to reduce the friction in the moving parts of the engine. The engineer opened the throttle and ran the engine for me for a few moments. It purred like a sewing machine.

LAURIE ELLEN has been certified by the U.S. Coast Guard to accomodate 18 passengers in her roomy cabin, however, Juneau Steamboat Company limits the number of persons carried to 16 for passenger comfort. The boat makes runs from the downtown cruise ship lightering float over toward Douglas. The crew gives tourists a description of Juneau's mining history and the history of the little steam launches that operated on the Gastineau Channel between Juneau and Douglas for many years until the bridge to Douglas was constructed in the 1930's..

For more information about the LAURIE ELLEN and her new sister vessel that will start operation in Gastineau Channel this year see the Juneau Steamboat Company web site at

http://www.juneausteamboat.com/
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Tel: (907) 789 0172

Fax: (907) 789 6964