HNoMS Børtind (J-394) - A requisitioned Whaler, armed as a minesweeper and served during WW2

Til_Dovre_Faller · September 1, 2024, 9:58pm

HNoMS BØRTIND (J-394)

TYPE: ex whaler/guard boat/Minesweeper
OLD NAME: Cape Royds, Merok, Myna
PREVIOUS OWNER: A/S Nordlands Fiske export, Bodø
BUILDING SITE: Cook, Welton & Gemmell Ltd, Beverley, England
LAUNCHED: January 1912
IN COMMAND: 1939 - 05.1945
WAR OPERATIONAL: 13.01.1941 In Great Britain

ARMAMENT

Spoiler

1x 3" 12pndr Fast Firing Cannon
-Caliber in metric: 76.2mm
-Barrel length in calibers: L/50
-Placement: Bow
-Mass: 12 cwt (0.6 tonnes, 510 kg)
-Length: 3.12 m
-Barrel length: 3 m
-Caliber: 7.62 cm
-Breech: single-motion screw
-Elevation: mounting dependent
-Traverse: mounting dependent
-Rate of fire: 15 rounds per minute
-Muzzle velocity: 670 m/s
-Effective firing range: 10,740 m at 40° elevation
-Feed system: Breech-loaded
1x 20mm Oerlikon Mk.II

-Barrel length in caliber: L/70
-Placement: in the aft of the ship, on a platform a litte above deck
-Total gun barrel weight: 68.04 kilograms
-Minus breech mechanism: 20.86 kg
-Overall: 2,210 mm
-Barrel length: 1,400 mm
-Shell L70: 20×110mmRB
-Rate of fireL70:
-Cyclic: 450 rounds per minute
-Practical: 250-320 rounds per minute
-Muzzle velocity L70: 820 m/s
-Effective firing range L70:
-Against low-flying aircraft (HE round): 914 m
-Maximum firing range HE round at 45°: 4,389 m
-Feed system: Cylindrical magazine holding 60 rounds, Later adjusted to be a belt fed gun
2x1 12.7x99mm Colt MG/52 Machinegun

-Cooling system: Water cooled
-Placement: Should be behind the chimney on each side
2x1 .303 Lewis Machinegun

-Placement: 1x on each brigde wing, attached picture are of these exact rifles!
-Armor: Armored shields, 3-10mm
-Mass: 13 kg
-Length: 1,283 mm
-Barrel length: 673 mm
-Width: 114 mm
-Cartridge: .303 British
-Action: Gas-operated long stroke gas piston, rotating open bolt
-Rate of fire: 500–600 rounds/min
-Muzzle velocity: 744 m/s
-Effective firing range: 805 m
-Maximum firing range: 3,200 m
-Feed system: 47- or 97-round pan magazine
-Sights: Blade and tangent leaf

Minesweep
-SA Gear Type Mk.IV
-Spring hammer Mk.I
-Towed B

TECHNICAL DATA
Displacement: 328 Gross tonnage
Length: 42.67 Meter
Width: 7.28 Meter
Depth: 3.74 Meter

MACHINERY
1x Triple expansion Nyland steam eigne
Power: 535 Indicated Horse Powers
Speed: 10 knots (18.52 Km/h)
Bunkers: 140 Metric Tons of Coal
Range : 4150n. miles at 8.5 knots (15.74 Km/h)

CREW
Estimated crew: 21 Men

HISTORY
The Norwegian Navy’s previous experience in demining was only neutralizing drift mines during and after the First World War. These were isolated cases, because no minefields had been laid out in Norwegian territory. It was not until the early thirties that it was realized that this could become relevant. It was therefore decided to equip six decommissioned Class 2 torpedo boats as combined guard boats and minesweepers. The torpedo guns of these vessels were taken ashore, and on a platform aft an arrangement was set up for Oropesa sweep. Incidentally, there is very little information about the equipment on these vessels. The Oropesa sweep was developed by the Royal Navy during the First World War and was named after the trawler Oropesa which first tried this type of sweep.

The Oropesa sweep, or O sweep as it is also called, consists of a cable or wire that the vessel releases. An otter is attached to the end of the cable, which causes the cable to pull outwards from the vessel. To mark where the otter is, there is a float on the surface, called a Paravan. Along the cable there are knives that will cut the anchoring of any mines so that they float up and can be neutralized. Another otter is attached to the inner side of the vessel, so that the sweep cable cuts into the water. The system is the same as on a trawl. The O-sweep, which is operated by one vessel, was a necessary further development of the English A-sweep. This consisted of a cable, pulled between two or more vessels. During an attack, it was very difficult to maneuver with the A-sweep in the sea. The growing threat of war and thus the danger of minelaying in Norwegian waters meant that, in addition to the rebuilding of the 2. kl. torpedo boats, it was decided to build two minesweepers. These, OTRA and RAUMA, were built at Akers mech. Workshop and were completely new and fully equipped when Great Britain announced that they had laid mines at Stad, Hustadvika and Landegode north of Bodø in April 1940. OTRA and RAUMA were in Horten and had received orders to go to Western Norway to clear the minefields, but was instead involved in the fighting at Horten harbor after the German attack on 9 April. OTRA was, following reports of foreign warships in the Oslofjord, sent out to observe and was able to 04.10 report that these vessels were German. RAUMA joined OLAV TRYGGVASON in battle with the German Raumboot R.17 and R.27 at Horten harbour. R.27 fired at RAUMA and badly damaged the vessel. The Chief, Itn. I. K. Winsnes, and one deckhand was killed and six others wounded, OTRA became the Germans’ prey at the quay at Filtvet, was named TOGO and was used as a guard boat until the navy got it back in 1947. Then OTRA was converted into a training vessel for minelaying.

It was after the rebuilding of the guard boats Bjerk, Syrian, Børtind, Nordhav II, Thorodd and Hval V that the navy got to try its hand at minesweeping duty in Great Britain. These were the vessels that made it over to Great Britain after the fighting in Norway ceased in June 1940. In addition to these, the navy took over its first vessel from the Roy Navy. It was the trawler ALCMARIA, equipped as a minesweeper and under Norwegian command from 15 October 1940 to 28 November 1944. The next minesweeper taken over from the Royal Navy was actually Norwegian. The whaleboat POLAR VI was requisitioned by the Royal Navy as early as March 1940 and transferred to the navy in February 1941. The minesweepers were first stationed in harbor towns on the east and north coast of Scotland. Later, it became most practical to gather the Norwegian minesweepers in a separate Norwegian minesweeper division, which had its station in Dundee.

After the end of service, the ship was returned to the original owners in 1946, when the ship was very worn. In 1963 the ship was sold to A/S Tromsø Trålfisk located in Tromsø, Norway and renamed TROMSØ IV. in 1966 again the ship was sold to Kyrre Bogstrand and renamed Lenviktrål. in 1975 it was sold to Lenvik Havfiskerselskap A/S and in June of the following year 1976 unfortunately sold for scrapping.

SCETCH OF THE VESSELS REBUILDING PLANS