Feb 18

The Life & Service of a World War 2 Mine Warfare Sailor. Part 7

Tuesday, February 18, 2020 12:01 AM

By

This blog begins on 10 June 1944. My grandfather, Seaman Thomas Schreck, joined his ship the USS Sway (AM-120) an Auk class minesweeper in Bizerte, Tunisia at the end of May. The ship just spent the last nine days undergoing refitting and maintenance and was now about to get underway once again to resume operations off the coast of Italy. Before returning however, they stopped in Malta to prepare the ship for the dangerous job of clearing mines.

Before getting into the ship’s operations, I want to provide some information on the USS Sway. The Sway belonged to the Auk class of fleet going minesweepers. Ninety five were built and used by both the U.S. and British navies. Of the 95 built 22 were used by the Royal Navy and designated Catherine class minesweepers. (1)

Auk Class Specifications

Type Minesweeper
Displacement 890 BRT
Length 221 feet
Complement
Armament 1 3 inch gun
2 40mm guns
8 20mm guns
Max speed 18,1 knots

The USS Sway was commissioned on 20 July 1943 and fought in the Italian campaign during Operation Shingle. By the time my grandfather came aboard, the ship was operating out of Bizerte in Tunisia.

After my grandfather joined the ship, he was ordered not to keep a journal. Though there were a few intermittent entries he never kept a daily journal again. The rest of his record that follows is pieced together from the ship’s muster roles, the ship’s war journal, and his own personal account. The entries from this point on come from the ship’s war journal unless otherwise noted. Reading the ship’s entries led me to study mine warfare at the time in more detail as well as the operations the Sway was involved in. Mine and anti-mine warfare is not an area covered in great detail by most historical accounts. It rarely involved the direct combat action that other naval vessels saw, however, without anti-mine operations, the major amphibious operations of World War II would have been far deadlier.

 

USS Sway (AM-120)

10 [June] 1345-Underway Singly from Bizerte to Malta to run Degaussing Range.

11 [June] Underway as before enroute to Malta. 0816 Moored alongside tanker Ohio on Renella Bay, Velletta Malta. 1404- Running Degaussing Range off Velletta Malta. Moored in harbor at Velletta Malta overnight.

Degausing was a technique to demagnetize the metal hull of a ship. One of the most dangerous mines used during World War II was the magnetic mine. Over time a ship’s hull would build up a natural magnetic field and when magnetic mines were dropped by ships or aircraft they would settle to the bottom in shallow areas. Once they were disturbed by a magnetic field from a passing ship they would detonate and could cause major damage to a vessel. To combat this two, main degaussing methods were developed to protect naval vessels. The first was a large degaussing coil that would be carried aboard ship and wrapped around part of the hull to demagnetize the vessel. The second mentioned in the above entry was a degaussing range. By running the range like the one pictures below it would greatly reduce the magnetic signature of a ship. (2)

German Turtle Mine

 

Degausing Range

13 [June] 0755- Anchored in Naples Harbor.0940 underway for Anzio, Italy in accordance with orders from NOIC Naples. 1758- Arrived Anzio. Commander R.C. Brown USN (COMINRON6) came aboard. 2330- underway for Civertta Vecchia Italy.

14 [June] Enroute to Cirvette Vecchia Italy, 0725- anchored in Cirvette Vecchia. 1207-Underway proceeding to Naples in accordance with verbal orders of CominRon 6. 2200-moored alongside USS Prevail in Naples Harbor.

Even though my grandfather was no longer writing regularly in his journal, he did write down impressions of places he visited. Of Naples he wrote “Just Like the States”

USS Prevail (AM-107) sister ship to the Sway

16 [June] 0701-Underway in company with USS Steady enroute to Anzio in accordance with NOIC Naples 151842 June Conducting routine sweep of channel with “O” and “A” gear on the way. Relieved USS Dextrous (AM341). COMDIV 18 came aboard and hoisted his pennant.

My Grandfather’s impressions of Anzio.

“Anzio- Nothing Plus”

USS Steady (AM-118) sister ship to the Sway

 

USS Dextrous AM-341 sister ship to the Sway

17-26 [June] At Anzio- Able patrol conducting routine mine sweeping operations with “M” “O” and “A” gear in company with USS Steady (AM118). Acting SOPA at Anzio and charged with defense of the harbor and sweeping operations. Relieved by USS Dextrous (AM341) on 26 June- Proceeded to Naples.

The “M”, “O” and “A” gear mentioned above refers to three types of mine sweeping gear used by the sway: magnetic, oropesa, and acoustic.

A magnetic sweep utilizes a magnetic field to simulate the field created by a passing ship. A magnetic field can be produced via an electrical current passing between two non-insulated cables. This resulting field will induce magnetic mines to detonate.

Under the Geneva convention underwater mines should be designed to be rendered inert if released to the surface, so in theory using the O sweep would do so. Sweeping for contact mines was by the Orepesa or Double O sweep. This comprises a serrated wire cable where one strand was twisted in the opposite direction to the others to give a rough cutting surface. At the tail was an otter, a metal device to make the sweep wire run out horizontally at an angle. This was suspended from a paravane float by a pendant to ensure the otter ran at a fixed depth. At the end nearest the ship was a kite This worked like a child’s toy only opposite by going down rather than up. This depressed the leading end of the sweep so it all ran at a constant depth. This collection of heavy metal work extended up to 500 yards astern and up to 200 yards to the side. At best a speed of 10 kts could be achieved.

An example of an A gear, or acoustic gear, would be Influence sweeps. These used equipment that was often towed and emulated a particular ship’s signature, thereby causing a mine to detonate. The most common such sweeps are magnetic and acoustic generators.

The use of O gear for cutting a mine to bring to the surface.

27 [June] Underway from Anzio to Naples on Route “W” accompanied by U.S.S. Steady escorting convoy of Liberty ships in accordance with visual orders from BNLO Anzio. 0712-Anchored in Naples. 1229- Underway enroute from Naples to Salerno, in accordance with orders from NOIC Naples. 1525- Arrived Salerno – Moored alongside U.S.S. Planter. 2230- Underway from Salerno en route to Palermo Accompanied by YMS 43 and 83 escorting LST 77,178, 211, 263 in accordance with orders from AATB Salerno 271835B.

29 [June] At Palermo taking aboard fresh provisions for Escort Sweeper ships. 1600- Underway from Palermo to Salerno Accompanied by YMS 83 in accordance with orders Commandant NOB Palermo.

My Grandfathers impressions of Salerno and Palermo.
Salerno- Not so bad
Palermo- Pretty good

30 [June] Underway as before. 1044- Anchored -Salerno 1055- commenced practice assault sweeping and landing operations with Group 2 of Task Force 81. Commander R.C Brown USN directing sweeping operations. Commander E.A. Ruth J.R., ComDiv 18 aboard. Sway acting as Flagship and guide for practice operation. 1739- Secured from practice operations. Anchored in Salerno.

The copy of the Sway’s war diary I found did not include the month of July. Records indicate the Sway spent July shuttling back and forth between Italy and Tunisia. The next blog will pick up in August with the Sway preparing for Operation Dragoon.

Enjoy the author’s earlier posts here:

https://www.navalhistory.org/2019/08/14/the-life-service-of-a-world-war-2-mine-warfare-sailor-part-1

https://www.navalhistory.org/2019/09/19/the-life-service-of-a-world-war-2-mine-warfare-sailor-part-2

https://www.navalhistory.org/2019/10/15/the-life-service-of-a-world-war-2-mine-warfare-sailor-part-3

https://www.navalhistory.org/2019/11/21/the-life-service-of-a-world-war-2-mine-warfare-sailor-part-4

https://www.navalhistory.org/2019/12/17/21-the-life-service-of-a-world-war-2-mine-warfare-sailor-part-5

https://www.navalhistory.org/2020/01/16/the-life-service-of-a-world-war-2-mine-warfare-sailor-part-6-sea-stories-part-1

Sources:

https://www.uboat.net/allies/warships/class/226.html

https://eeuwen.home.xs4all.nl/Degaussing.htm?fbclid=IwAR115Vg6GRgen_qOEVmOrAMU-fm1AqefJj_NW2-gg3Ks6c21pQrjNssPQEU займ онлайн