ALTHOUGH OFTEN REFERRED TO as an armed trawler, the wreck of the Admiralty trawler Benton Castle does not show any of the guns or depth charges normally associated with this type of vessel.
Her main role was to patrol the approaches to the harbour at Dartmouth and to keep them clear of mines, until , that is, she struck one herself. The wreck now rests leaning to port on the silty 40m seabed, in a 3m-deep scour, a few miles almost straight out of Dartmouth.
When I dived the Benton Castle, the shotline was hooked across the trawl gallows frame on the starboard side (1) just behind the forecastle, so that is where our tour begins, meeting the highest point of the wreck at 33m.
The main deck must have been supported by wooden beams, because no sign of it remains. However, the forecastle (2) rises above the main deck and has a steel deck to provide strength for the various deck fittings.
Railings are still in place at the back of the forecastle and to either side, covered with a particularly dense coating of plumose anemones.
Towards the front of the forecastle, a small anchor-winch (3) spans most of the width of the deck, with small pairs of bollards to either side.
Chains stretch from the anchor winch through the hawse pipes. Just over the bow, both port and starboard anchors remain in place, held in tight by the chains (4).
A heavy hawser (5) is draped over the port side of the bow, leading out a little way before disappearing into the silt.
This will not have been part of the fittings of the original Benton Castle, as rope of that age will have rotted away.
More likely, this is the result of a more recent trawler snagging its gear on the wreck.
Aft of the forecastle, the hull is just a shell with various deck-fittings fallen to the bottom of the hull. Between the trawl gallows, a small winch supported by a triangular trestle (6) has fallen backwards. Above this, a steel beam with a keyhole at the end would have been attached to the wooden mast.
To the starboard side, a big hole in the hull (7) shows where the Benton Castle fatally struck a mine. Across to the port side, the hull is all there, but split outwards (8) as the keel twisted with the explosion and subsequent impact with the seabed. Just aft of the split, a small horizontal capstan of the type used to haul lines of pots is located against the side of the hull (9).
Further aft, the central area of the deck and lower parts of the superstructure were of steel, so are more intact. The frames on which this was supported have decayed, the whole aft area of deck dropping into the hull.
A big trawl-winch (10) spans the deck. Behind it, the wheelhouse base rises slightly, though the wheelhouse, being wooden, has long gone. Mounted centrally, the helm (11) remains in place, although, as with the railings, you have to look carefully to make out any details beneath the masses of anemones.
The level of the deck drops again behind the wheelhouse. An oval hole above the boiler marks where the funnel would have fitted (12). The funnel itself rests just off the port side, partially buried in the silt (13).
Back on the main body of the wreck, another arched gallows (14) protects the superstructure from the trawlers own cables. A small hatch in the deck (15) leads down to the boiler and engine, though on a seabed this silty I wouldnt risk trying to get inside.
The deckhouse above the engine rises further to give some headroom. To the top of this, the usual skylight (16) with open hatches provided ventilation for the engineers and stokers.
We are now above the stern, with a simple tiller-bar steering (17) at the top of the rudder-post. The end of the tiller-bar would have been connected to chains or cables running either side of the trawler to connect to the helm (11).
Dropping beneath the stern, the 3m scour drops low enough to expose the propeller and rudder (18). The rudder is hard to port, corresponding to the position of the tiller-bar above deck.
Rising on the starboard side of the stern (19), small pairs of bollards are located to either side of the steering.
A little further forward, the starboard trawl gallows (20) provides a convenient location to pop a DSMB for a drifting ascent and decompression.

Thanks to Steve Mackay, Andy Micklewright and Rick Parker.

GETTING THERE: From the M5 and then A38, turn left on the A380 and A3022 for Torquay.
HOW TO FIND IT: The GPS co-ordinates are 50 18.537 N, 003 31.720 W (degrees, minutes and decimals). The Benton Castle lies in a scour 3-4m deep in a silty seabed. The bow points to the north-west.
TIDES: Slack is three hours after high water Dartmouth or two hours before high water Dartmouth, with the best visibility being after high water.
DIVING: Jennifer Ann, 01803 607704, www.deepsea.co.uk/boats/jenniferann
AIR: Riviera Diving & Watersports, Torquay, 01803 607135.
ACCOMMODATION: Tor Dean Hotel, Torquay, 01803 294669.
QUALIFICATIONS: An advanced air dive suitable for anyone with PADI Dive Master/BSAC Dive Leader qualifications with advanced nitrox and decompression procedures.
LAUNCHING: Slips at Paignton, Brixham and Dartmouth.
FURTHER INFORMATION: Admiralty Chart 3315, Berry Head to Bill of Portland. Ordnance Survey Map 202, Torbay & South Dartmoor Area. World War One Channel Wrecks, by Neil Maw. Dive South Devon, by Kendall McDonald.
PROS: Compact enough that it can be seen all on one dive without getting too far into decompression.
CONS: Visibility can be low, especially after heavy rainfall.

One of the anchors, still in place.

The small anchor-winch.

Engine-room ventilator hatches, silted inside.

Trawl winch.

Spar from the trawl gear.

Steering binnacle and helm.


-20m width=100%

THE BENTON CASTLE, trawler/minesweeper. BUILT 1914, SUNK 1916

THE GERMAN MINE-LAYING SUBMARINES of World War One never abandoned Dartmouth. Month after month, year after year, these UC-class boats let the mines fall from their chutes in places just off the port where they reckoned they would catch inward and outward traffic, writes Kendall McDonald.
They were very successful, so much so that, even early in the war, the Navy laid deep minefields off Dartmouth.
It hoped to catch U-boats lying in wait to replace the mines that had claimed victims in shallower and smaller fields laid earlier by other UC-type minelayers.
Many of the victims of these U-boat-laid minefields were the smaller ships that made up a great deal of the Dartmouth traffic.
Typical of these were the fishing trawlers hired by the Admiralty, armed and turned into patrol mine-sweepers. An early victim was the Benton Castle, a 283-ton trawler that had been built in Middlesbrough in 1914.
She was 130ft long with a beam of 22ft and a draught of 13ft. Her engine was an 85hp, three-cylinder triple-expansion unit with a single boiler.
She was first registered as a trawler at Swansea, owned by Castle Steam Trawlers Ltd, from which the Admiralty hired her in 1915. She became HMS Benton Castle, Patrol Sweeper No 1972.
She was on patrol off Dartmouth on 10 November, 1916, when she ran into a cluster of German mines laid the night before by one of the small early UC-boats, fitted with six chutes for carrying a dozen mines.
The mine explosion blew a gaping hole in the Benton Castles bow on the port side. She sank so swiftly that all 10 of her crew were lost.