HMS Niger Minesweeping Reports March

Source: ADM 199/184 Mine clearance sweep by Fifth MSF (Extracts)

From:       The Senior Officer 5^th M/S Flotilla, HMS GOSSAMER
Date:       26^th March 1940
To:        Vice Admiral Commanding, Dover

Report of Clearance Operation on Easter Sunday 24.3.40 and Monday 25.3.40.

Submitted: This clearance was delayed by thick fog until 1600 on Sunday when sweeping was commenced and continued until 1900, vessels anchoring in the vicinity for the night.

Sweep recommenced at 0900 on Monday which was the earliest that tidal conditions permitted, and was continued until 1745. No further mines were discovered, the area having been thoroughly searched the previous day.

Danlaying yacht Sargasso was of great assistance, but Grey Mist who was also detailed apparently proceeded to expend his ammunition on floating mines and returned to Ramsgate to replenish it. He did not appear at all. One sweeper had to be used for danlaying.

Sweepers: Gossamer, NIGER
Danlayers: Salamander, Sargasso

Points of interest:-

Possible Anti-Sweeping Device

On Monday 25^th Leda’s sweep was parted by an underwater explosion. The explosion was slight but definite, and was followed by a ring of bubbles on the surface, some 15 feet in diameter.

Two alternative suggestions are:

a) A mine whose main charge failed to fire.

b) An explosive cutting device.

Against a) no other mines in this field have exploded on being swept.

Against b) the position was immediately danned by Salamander who was following astern. It was re-swept at the end of the day and nothing found.

Another peculiar occurrence for which no explanation is suggested, was a parted sweep on the previous day. In this case the sweep was found, on recovery, to have 80 fathoms missing, ie it had parted in two places.

Asdic Contact

While at anchor during the night NIGER obtained a doubtful contact. One depth charge was dropped, after which it was considered the contact was definitely non-sub. I consider NIGER’s constant anti-sub vigilance, especially after a hard day’s sweeping, is most creditable. She is the only asdic vessel in the flotilla.

R Ross

Commander

SO 5^th M/S Flotilla

Source: ADM 199/184 Mine clearance sweep by Fifth MSF (Extracts)

Minesweeping Reports on Operations 29^th March to 1^st April 1940 (extracts)

From: Senior Officer, 5^th M/S Flotilla, HMS Gossamer
Date:    31^st March 1940
To:       Vice Admiral Commanding, Dover

Clearance sweep on 29^th March 1940

SCZ 125 from Centre Line to 1 ½ miles South between meridian 2° 00’ E and 2° 07’ E.

Sweepers:         Gossamer, Harrier, NIGER, Speedwell
Danlayers:        Sargasso, Comfort, Nautilas

No mines were encountered till the signal for ‘in sweeps’ was about to be hoisted in the SE corner of Area, when one was cut by second ship. German type ‘Y’ moored mine, sunk by gunfire. Cross tide sweeping was necessitated by the fact that only one danlayer was available capable of the speed of the flotilla. There were several partings but these are attributed to old wires and bad weather. There was no evidence of any anti-sweeping devices.

R Ross
Commander
S.O. 5^th M/S Flotilla