So, as I research and write, I am still thinking of how to provide these multimedia items that would be outtakes in a normal published book.

I am experimenting with this blog, by posting movies, and many of the backgorund research items that would normally only appear in a bibliography or index, and maybe by the time I finish the book – the answer will be obvious. At the moment, a website organized by chapters, or a DVD Set to complement the book may be in order. But, who knows what technology will spawn in the future.

BTW: The Sin Do Island, North Korea Invasion using COMINRON 3 LCVP’s to deliver Republic of Korea infantry, may be one of the only beach invasions made by minesweeping boats in Korea. The MR3 LCVP’s have their bow ramps welded shut, which made it very difficult for the ROK troops to disembark. It was a good thing that North Korean troops were inland!

Chinnampo & Sin Do Invasion

Dutch was a battleship and aircraft carrier sailor in wWII. He was a BM2 and a Boat Captain in 1950 when arriving in Sasebo. Their boats were carried by APD’s, LST’s, LSD’s, and once late in 1950, slung crossways on the stern of an ASR. As you can see on the video, his crewmembers kept track of the Russian mines they swept in Korea. MSB ONE and COMINRON THREE AMC’s maintained an 800 day seige of Wonsan North Korea throughout the entire war.

Dutch Schultz-Minesweeper Sailor

An article I wrote in 2005 while serving as the Vietnam Editor of the Minewarfare Asssociation publication The Silent Defenders is attached:

The Long Tao Sweepers

Adm Bolt told this story in a 1979 article for Air Pictorial, a British magazine: Minesweeping Wellingtons

The very next day November 23, 1939 a German Magnetic Mine was discovered in the mud flats (visible at low tide) near Shoeburyness on the Thames River. the men dispatched from H.M.S. Vernon
(the RN name shore facilities the same as ships) dismantled the mine and learned it had magnetic triggering, the first know use in WWII.

First German magnetic mine – Shoeburyness, UK 1939

The British, between WWI and WWII had a very active RN minesweeping research program, and continued to develop mines and countermeasures, and were readying their LL Sweep Gear towed by minesweepers to detonate magnetic mines far behind the minesweepers using strong magnetic fields. The danger however, was that the minesweepers had to first pass over these bottom mines without detonating them. The LL Sweeps were in development, but not yet ready to deploy. The H.M.S. Borde was hastily fitted with a large electromagnet in the bow, and worked great until exposions endered it too dangerous.

The C-in-C First Sea Lord Winston Churchill informed LCdr Bolt that Vickers had been ordered by the Admiralty to convert some Wellingtons to act as flying magnetic minesweepers, and that he had been appointed to navigate them over the minefields. It was thought the speed of the aircraft would clear it from the explosion without harm.

The development story is quite good, and the testing with the magnetic trigger from the Shoeburyness mine trigger mechanism connected to flashbulbs, confirmed no pretriggers before the bomber was overhead. It was determined that the bomber fly at 50-70ft elevation, at 150 knots to clear the explosions. The safe depths were first set at 60 ft, but later reduced to 36 ft. The first mine detonated recorded a 3.5 g “bump” at the tail, they continued lower (below 35 ft), and had more success – but the the “bumps” were now recording 10 g’s on the accellerometer!

These are quite interesting experiments, first as minesweeping progressed, these jobs were turned over to wooden minesweeping boats (and partially degaussed trawlers), when LL sweeps were designed for smaller craft. Larger minesweepers had too much draft for rivers.

Some Luftwaffe Ju 52 floatplanes were also used as minesweepers, fitted with a large degaussing ring under the airframe. These particular Junkers Ju-52-3m were used as a minesweeper, and attached to the Minensuch-Gruppe, then based in France during 1943. The large ring was an electrified metal alloy affair built in sections that were supported with bracings under the fuselage and wings. Low voltage current was fed through the ring while the aircraft was flying over the water suspected of being mined by the Allies. The electromagnetic field generated by the minesweeping ring would explode any magnetic mines encountered. Based on the French coast, the Mine sweeping squadron remained operational until late 1944.

Ed Sinclair.

Ted Sammon an All Hands writer wrote an article at the end of the Korean War on LSD’s, USN Landing Ship Dock ships utilized in a new role during Korea as mine sweeping mother ships. This concept was first developed by the German Reichsmarine in WWI, called Minenraummutterschiffe’s.They used obsolete dreadnaught battleships, (pre-1910), removed their massive guns topside, and replaced them with boat skids, where they carried 14-18 57′ motor launch-like boat minesweepers called F-Boote’s. These boats were carried to the mined areas, and launched via cranes ahead of the German fleet to clear a path to the Atlantic; The Allies (UK and America) planted the “North Sea Mine Barrage” consisting of several mine lines stretching across the Noth Sea from Scotland to Norway to bottle up the German Fleet and U-boats in the North Sea in WWI – and repeated this mining effort in WWII. The German Kriegsmarine used the same concept during WWII, using primarily modern cargo ships, Modifying a total of eight captured and two Kriegsmaring ships, designated MRS = Minenraumschiffe.

The ballasting and launching of the LCVP’s directly into Wonsan harbor described in the article was changed in mid-1952 after North Korean artillery struck the USS Cabildo during this ballasting-deballisting process. Every boat had to stay manned while the well deck was flooded, until it was drained and sailor power chained the boats down with appropriate lumber supports. Later, the Navy changed the process to launch MSB’s by the use of the LSD’s cranes. Four remaining LCVP’s containing heavy submarine batteries that powered their magnetic minesweeping cables, could not be launched by crane, because their plywood construction would not hold the weight of these batteries. Therefore, they were still launched out the stern gate of the LSD (Four Boats Only) with a partial ballasting. They would then back up to the LSD stern first to accept their 1,500 foot magnetic tails, previously flaked down in the well deck.

See two previous posts on this Blog Aug 2, 2012 and Aug 9, 2012 including the movie of the LSD ballasting down in 1952.