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Any successful people Towing a Metal Detector out there looking for Aircraft Aluminum? I have been using a Fisher Pulse 10 on a sled.

Working in Fresh Water small Lakes. Can detect beer cans and silver dollars if on a solid surface.


3 Answers

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What has been your experience underwataer? How big is the search coil?


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The Dish measures 18" in Diameter. I have been searching for a T-33A Jet Trainer 52-9639A with two crewmen still in the craft. The Aluminum makeup of this single engine aircraft is: (NACA 65 (1) 213 Airfoil.) Its considered exotic metal and has a poor return on the Fisher Dish which I have used since 1991. The aircraft crashed Dec 8 1956 around midnight. Last Radio Goshen, IN. at 23:46. I gave up on the Torpedo with Altimeter early while using the Dish. I built a sled out of PVC Plastic and placed down rigger wings on it. Using a down rigger with the sled it really hugs the bottom very effectively. It has been a real learning lesson for me. I have a 20' boat with Tow frame and two (2) Down looking Lowrance SONARS. I will help or answer any questions asked. MC
Have you actually tested the detection capability of the 18" coil with a similar T33A Jet trainer?

If the aircraft is buried then you may need to use a larger coil such one with a 1 meter diameter for greater depth. You need to consistently keep the coil about 1 foot off of the bottom all the time, at least enough to reject random small metallic junk. Weight the sled so that it is always on the bottom when towing it. Of course, keeping a tight and precise grid is very important. If you are doing all of the above then I expect that you may be searching in the wrong location. You also might consider towing a drop camera and record with GPS data embedded on the screen to provide a larger area of detection. If you are operating in 75 ft or water or less, buy or borrow a Hummingbird side scan sonar. Any deeper than that and you will need a towed side scan such as a DeepVision DE-340. Hope this helps. Jim –  JimKennard  Jul 4th, 2013 at 9:41 PM
Thanks for the feedback. We have used 3 different sidescan SONARS. Started with LORAN then DGPS now GPS. Familiar with the Hummingbird, the Lake of most search is 62' deep. Looked into Sub-Bottom Profiler from Imagenex. $22,000.00 There are 100 Lakes in the county of concern. Also, Swamp, Bog, Fen etc. Could you fill me in on your experience while using a Towable Metal Detector. What has been some of your finds, as well as problems encountered and resolved. Thanks again look forward to hearing from you. Mike Carpenter –  mc2dive  Jul 4th, 2013 at 10:12 PM
My experience with UW metal detecting is in shallow water. The references to search coil and towing come from suggestions obtained from other successful UW TH'ers. What side scan sonars did you use? If you could not find the aircraft with side scan sonar and assuming it is not buried or has been previously removed, then you might not be in the right location. –  JimKennard  Jul 5th, 2013 at 12:10 AM


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I have used a Fisher towable metal detector. Unless you run directly over a large metal object and the detector is within 5 feet we did not get any response. I used a length of 4 inch plastic tube filled with concrete to keep the detector down. It was about as successful as dragging a grapple hook. I did have better luck dragging a video camera but unless you have very clear water you will cover a very small area of view. I purchased one of the new humminbird D. image sounders and it looks like it shows promise. If you cannot afford a side scan you might want to think about a magnetometer. Good luck and keep on searching.

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