[Acoustics] Rigging a Rio Grande and Riverboat to deploy off the bow

[Jeffrey J Kvech]

We're looking at making up a temporary rig to use a 1200kHz Rio Grande 
with an Oceanscience Riverboat extended off the bow. I'm hoping some of 
you can give me some hints as far what to do, or not do, as the case may 
be. On this particular boat, an electric trolling motor is mounted on the 
front, and will be in use, so we'll need to extend the ADCP some distance 
(5ft? 10ft?) beyond the motor. I have two questions related to the 
electric motor...........first, how far away is far enough so that the 
prop (which, according to the plan, will stay downstream of the ADCP) 
doesn't affect the measurement, in terms of disturbing the flow? ; and, 
second, would the electric motor cause any interference that we might need 
to worry about?

Thanks for any info.

Jeff Kvech, Hydrologic Technician, U.S. Geological Survey
Maryland-Delaware-D.C.  Water Science Center
8987 Yellow Brick Rd., Baltimore, MD 21237
(office)410-238-4244;  (mobile)410-925-8581
jjkvech at usgs.gov