Looking back at the list of Wreck Tours, I realise that its been ages since we featured a submarine, the last one being the UC70 off Whitby (Wreck Tour 10, December 1999). So for all those submarine fanatics who have been so sadly neglected, this months tour is of HMS Umpire, a World War Two wreck in only 18m, located 15 miles off the north Norfolk coast.
     When I dived HMS Umpire the shot had caught just aft of amidships (1). The submarine lies on its starboard side, so the upper surface here is the port side. Looking forward, the keel is to the left and the deck to the right.
     This shallow, there is plenty of natural light, which serves to enhance visibility. The hull is coated in a dense carpet of hydroids, with clumps of big plumose anemones on exposed ribs.
     Heading forward, the hull is soon broken and collapsed where the main control room would have been beneath the conning tower (2). The wreck then gains more structure, with the lower part of the hull pretty solid, though the upper part is broken clear (3).
     Stacks of batteries can be seen through gaps in the internal deck, where rectangular plates have fallen clear.
     Fourteen of the 31 crew were lost when HMS Umpire was accidentally rammed by the Admiralty trawler Peter Hendriks, so this submarine should be treated as a war grave, with a look-but-do-not-disturb approach to diving.
     Having said that, what does and does not constitute venturing inside a wreck that has been blown open by commercial salvage can be a little ambiguous.
     To the forward end of the control room, an intact bulkhead separates it from the torpedo-room (4). The hatch that was closed so heroically when the torpedo-room flooded now lies open.
     Staying outside the hull, a section of bent pipe lies propped against the deck from the seabed, with cables draped over it. All are covered in anemones.
     The first feature of the bow deck is the torpedo-loading hatch (5), a sloped tube angled forward into the deck, through which torpedoes would be slid into the torpedo-room.
     The hatch-cover is open and hanging below, hinged to the starboard side of the wreck. Looking in, a green glow from the break further forward can be seen through the torpedo-room.
     Next along the deck comes the forward escape hatch (6), again open. The Peter Hendriks struck HMS Umpire near the bow, flooding the forward torpedo-room. While others escaped through the aft escape hatch, no one survived from the forward part of the wreck, so this hatch was most likely opened during subsequent salvage.
     The last item on this intact section of bow deck is a small anchor winch (7). This would normally have been enclosed by the outer hull, but the bow forward of here is just debris. Forward of the anchor winch, the wreck is cleanly broken pretty much completely across.
     Looking back inside the torpedo-room, what looks like a re-load torpedo rests on the lower side of the wreck.
     Further forward, the wreck is flat to the seabed, just a few curved plates rising above the sand, some with flanges and valves projecting (8). Its hard to tell just how much of this damage was done by the original collision and how much by subsequent salvage to recover the four torpedo tubes for their non-ferrous metal.
     A fair amount of wreckage has fallen away from the deck, so on the swim aft it is worth looping out a little, keeping the main body of the wreck in sight.
     One of the bow hydroplanes stands upright in the sand (9), just about level with the anchor winch.
     In addition to torpedo tubes, HMS Umpire was armed with a 12-pounder gun, a 3in gun and 3 x 0.303in machine guns.
     Just out from amidships, the mount for the forward 12-pounder gun lies on one side (10) with a section of hull-plate resting over the top of it. The gun itself is missing, presumably salvaged, or perhaps it is buried somewhere nearby. There are certainly no signs of it under the plate.
     Close to the base of the gun-mount, but still detached from the main body of wreckage, a curved section of metal partly buried in sand and gravel is the remains of the conning tower (11).
     The 3in gun can be found further aft, lying on one side half-submerged in the seabed and again separated from the main body of the wreck (12).
     From here our tour cuts in to the stern (13), where the rudder is an open framework angled slightly to port (up) and the diving plane angled slightly down. The port propeller-shaft projects on the upper side of the wreck (14), the prop itself being another item which would have been salvaged. The starboard shaft is buried.
     The tail section of the wreck is broken from the rest of the wreck where the engine-room has been broken open (15).
     I think the main objective of the salvors here would have been the copper from the electric motors, and the remains of what looks like the armature of an electric motor lies cleaned of its windings among the debris. It is from the engine-room escape hatch that the surviving crew swam to the surface.
     The members of the commercial salvage team certainly knew what they were doing. The wreck has been opened out completely, right where the main objects of salvage could be found: the electric motors, the control-room instruments and periscopes, and the torpedo tubes at the bow.
     The drive train of a submarine is linked in this sequence: diesel engine, electric motor/generator, gearbox, shaft, propeller. Looking back inside the tail section, the gearboxes are still attached to the propeller shafts, though as I have noted, they have been separated from the electric motors.
     Continuing forward, the wreck regains some structure (16). Beneath the internal deck are more batteries; submarines carry an enormous quantity of batteries for use when submerged, and these would be fitted the whole length of the hull beneath the internal deck, also serving as stabilising ballast.
     One of the diesel engines has fallen out of the wreck and is sheltered by a section of hull (17). The other lies partly obscured by debris within the main part of the hull. Ascending onto the port side of the hull brings our tour back to its starting point. With an 18m dive unlikely to end in decompression, the simplest ascent is back up the shotline.

Thanks to James Holt, Stephen Holt, John Martin and Dave King..

During the night of 19 July, 1941 His Majestys Submarine Umpire, with a crew of 30, was cruising on the surface with a large inward-bound Allied convoy off the Norfolk coast. On the conning-tower were her commander and two lookouts. Suddenly something went wrong with her steering, and she veered sharply into the path of one of the convoys escort trawlers, writes Kendall McDonald.
     The subs captain shouted: Full astern together! It was too late. The trawler was a dark mass above her, and then her bow sliced into the subs starboard bow. The two vessels clung together for less than a minute before the Umpire heeled to port and went down. The captain and the two lookouts were left on the surface, but both lookouts sank before help reached them.
     The 180ft, 540-ton Umpire settled on the seabed with a 30Â list to starboard. Four men in her control room managed to seal the compartment. They knew from the depth gauge near the periscopes that they were at 24m, and though they had no Davis escape gear they decided to make a free ascent from the conning-tower hatch without delay.
     They made a good exit and all four reached the surface, but two had held their breath and, though picked up, died later from ruptured lungs.
     Due to the list, the bulkhead door of the engine-room would not close properly and the compartment was slowly but steadily flooding. Twenty men had taken refuge here and prepared to escape using the Davis escape trunk. Only 17 had Davis escape gear, so three of those went first, with the three without escape lungs clinging to their legs. Two of the latter didnt make it to the surface, as they were knocked unconscious after hitting gear outside the escape hatch, and let go.
     A seaman called Killan then took charge of those left in the engine-room. First he ducked under water into the trunking, went up it to make sure it was all clear, and finally returned to the engine-room. Then he sent the others up one by one. He was the last to leave and was rightly awarded the British Empire Medal for his bravery.
     Those concerned about diving Umpire for fear that she might be considered a war grave should know that she was reported as sold for scrap after the war, and most of the damage to be seen today was caused by the heavy use of explosives by the salvors.

Gun pintle

a lobster beneath the bow plates

the rudder

and batteries


GETTING THERE: Head for Cambridge or Kings Lynn, then Fakenham, then follow the B1105 to Wells-next-the-Sea and the A149 towards Blakeney. Two miles before Blakeney, turn left at Morston at the sign for Morston Marina. Watch out for the vicious speed bumps. The tender runs from the first row of old wooden jetties.
TIDES: Slack water is essential and occurs three hours after high water at Blakeney.
HOW TO FIND IT: The charted co-ordinates are 53 09.9N 001 06.1E (degrees, minutes and decimals).
DIVING AND AIR: Dive Norfolk, skipper John Martin, boat Desert Moon (01604 407611). Compressor aboard.
LAUNCHING: Slip or beach-launching close to high water at Cromer, Blakeney, Morston and Wells. After diving you will have to stay out for the rest of the tide.
ACCOMODATION: Norfolk Dive Charters and Dive Norfolk provide B&B.
QUALIFICATIONS: Only 18m deep, so this wreck is suitable for those with minimal qualifications.
FURTHER INFORMATION: Admiralty Chart 108, Approaches to the Wash. Ordnance Survey Landranger Map 132, North-west Norfolk, Kings Lynn and Fakenham. The Shipwrecks of Norfolk, by Stephen Holt.

PROS: A nicely opened up submarine provides plenty to think about.
CONS: Harbours are tidal. Visibility can be unpredictable.