Sporting an icy mustache on her bow, CSL’s Whitefish Bay departed Duluth, MN, on the chilly morning of April 17, 2022, following an overnight delivery of salt to EnviroTech-Hallett Dock 8. On her way out of town, the Trillium-class self-unloader would give a strange salute on her Zöllner ZET-Horn 90 AC consisting of two long blasts and two short blasts. The whistle, mounted on the foremast, was sounding a little subdued on this particular day due to the cold, so the first blast may have been to “wake up” the horn. It steadily gets louder and more powerful during the rest of the salute. As usual, the Aerial Lift Bridge responded with a salute of its own to complete the exchange.
The ZET-Horn 90 AC is offered by German horn and whistle manufacturer Zöllner Signal GmbH, based in Kiel. Throughout its history, Zöllner has been a major supplier of ship horns for saltwater vessels - and more recently, Canadian newbuilds like Whitefish Bay - sailing the Great Lakes.
The ZET-Horn line is a series of electric piston horns. Each ZET-Horn model is given a designation # AC, where "#" is the approximate frequency of the horn in Hz and "AC" indicates that the electric motor uses an alternating current. The 90 AC has an approximate fundamental frequency of 90 Hz. A distinguishing feature of some of Zöllner’s large ZET-Horn models is the use of bright orange paint on the inside of the protruding bell. This can be seen at 0:30 in the video and serves as a handy feature for identifying ZET-Horns on other vessels you see.
The Whitefish Bay also carries a Zöllner Makrofon ZM 200/110b ZVE(E)(H) on her pilothouse mast.
All audio and photos are my own.
Intro video by VartanMercadanti, pixabay.com, free license.
Intro audio by kbeezy88, pixabay.com, free license.