NL Pontoon units were fairly common, especially in the Pacific. They were also used to construct sunken causeways on the D day beaches. So far I have found little detail of the means used to construct or operate them. I assume that sections were moved into place and allowed to fill with water, eventually forming a causeway 700 feet long. Does anyone have more details, or photos. There is a small section in the Neptune orders concerning their towing across the Channel. ' Tows consist of pontoon units, rafts, tug units and warping tugs. Certain of the tug units will be manned and in suitable weather can use their engines to assist.' This is the only mention I have seen of tug units. Any information on these would be welcome. Mike.
The portal says there have been no views of this thread. This is clearly incorrect since I have received two replies by various means and from shy members. I had some information since these pontoon units use the same basic components as the Rhino Ferry. I now know that the basic unit was a 5' X 5' X 7' welded steel box with internal bracing. It does indeed have four 2" plugged boiler flanges to which piping can be fitted for flooding or draining. Presumably for simple sunken causeways the plug can be removed to let sea water in. For the causeway strings of 15 units were fastened together with steel angles. Three strings were then fastened together with links, pins and tie rods to form a raft. Ten rafts were fastened together on site to form the causeway. There should be a ramp section at the shore end and an offshore section to provide connections with craft unloading. A tug could be formed from a raft fitted with a 115 hp outboard motor. So that is more or less the construction. Thank you. Mike PS. It says 20 views now.
