Out of any boats used for hydrographic survey and reconnaissance, from jet boat to cataraft, this is the one that gets the most reactions when it’s sitting in the parking lot: the airboat. If a cataraft allows you to say, “Who needs a boat launch?” then the airboat enables you to ask, “Who needs water?” A loud, versatile, dangerous (powered by an airplane prop!) and unique watercraft, why in the world would you ever need it for a hydrographic survey? The answer: sand!
While performing work to obtain a longitudinal profile and other cross section data on the Platte River, we first attempted to do this using our jet boats. Bad idea that we should have heeded some warnings about! Even in deeper parts of the river there was still too much sand getting sucked up into the engine, nearly destroying it! Enter the airboat. Notice the small frame around it? That’s for those fun wires across the channel so they go up and over the people in the boat instead of through them. You can see the survey set up below with the GPS and the transducer on the back and and the laptop for the data collection at the very front.
This beast can definitely go anywhere but, of course, it struggles in stronger current and deeper areas where the torque of the prop can tip it or swamp the back of the boat. Folks in our crews that have rode on it, or driven it, will tell you about how loud it is or the fear that the airboat puts in you on your initial rides. There are no brakes and no reverse, but for a shallow, mobile, sand-bed channel, you can’t find a better option, especially for reaches that measure in tens of miles.