HMS Umpire was sunk in a collision in the Second World War. The wreck lies on its starboard side in only 18 metres, located 15 miles off the north Norfolk coast.
This shallow there is plenty of natural light which serves to enhance visibility. The hull is completely coated in a dense carpet of hydroids, with clumps of big plumose anemones on exposed ribs.
The hull is broken and collapsed where the main control room would have been beneath the conning tower. The wreck then gains more structure, with the lower part of the hull pretty solid, though the upper part is broken clear. Stacks of batteries can be seen through gaps in the internal deck where rectangular plates have fallen clear.
14 of the 31 crew were lost when HMS Umpire was accidentally rammed by the Admiralty trawler Peter Hendriks, so HMS Umpire should be treated as a war grave with a look but do not disturb approach to diving. Having said that, deciding just what does and does not constitute venturing inside a wreck that has been blown open by commercial salvage is a little ambiguous.
To the forward end of the control room an intact bulkhead separates it from the torpedo room. The hatch that was closed so heroically when the torpedo room flooded now lies open.
The first feature of the bow deck is the torpedo loading hatch, 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, again open. The Peter Hendriks struck HMS Umpire near the bow, flooding the forward torpedo room. Whilst 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. 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. 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.
There is a fair amount of wreckage 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 site. One of the bow hydroplanes stands upright in the sand, just about level with the anchor winch.
In addition to torpedo tubes, HMS Umpire was also armed with a 12-pounder gun, a 3 inch gun and 3x 0.303 inch machine guns.
Just out from amidships, the mount for the forward 12-pounder gun lies on one side 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.
The 3 inch 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.
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.
The tail section of the wreck is broken from the rest of the wreck where the engine room has been broken open. I think the main objective of the salvors here would have been the copper from the electric motors, the remains of what looks like the armature of an electric motor lies cleaned of its windings amongst the debris. It is from the engine room escape hatch that the surviving crew swam to the surface.
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 the 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 they have been separated from the electric motors.
One of the diesel engines has fallen out of the wreck and is sheltered by a section of hull. The other lies partly obscured by debris within the main part of the hull.
The rudder is an open framework angled slightly to port and the diving plane is angled slightly down. The port propeller shaft projects on the upper side of the wreck, the propeller itself being another item which would have been salvaged. The starboard shaft is buried.