Every now and then, a dive sticks in my memory for some reason or other. Sometimes its the location, sometimes its the people, sometimes its the diving conditions and sometimes it just clicks and is hard to explain. I fondly remember the dive for years afterwards, and wonder whether I should return.
Its not always an easy decision. If the repeat dive is not as good as the remembered dive, it could end up blighting the memory. I might have been better off leaving it alone.
On the other hand, it might turn out even better.
With HMS Northcoates, it was not a tough call. Seven or eight years ago, when I last dived this World War Two armed trawler, the visibility was excellent and the wreck pretty much perfect. I have been looking for an opportunity to return ever since. Such an opportunity arrives with an invitation from Mole Valley SAC, which has adopted the Northcoates under the Nautical Archaeology Societys Adopt-a-Wreck scheme.
Mole Valleys invitation coincides with another to visit Littlehampton, from father and son team Vernon and Daniel Parker, skippers of charterboat Our Joy.
Fate smiles again with a July Saturday of mostly sunshine and a nice calm sea. Descending the shotline, visibility is a little odd. The first few metres are clear, then it becomes bitty, with lots of silt suspended in the water. My mind runs through the wisdom of returning. Could I be about to destroy a treasured memory Then, towards the bottom, most of the bits clear and HMS Northcoates spreads panoramically. I am already smiling about another memorable dive, and Ive only just started.
The shot rests on the sand just a couple of metres off the tip of the bow. First pair down, we spare a minute at 29m to drag it behind a bit of debris to make sure it stays there for the Mole Valley divers.
Looking up, the bow gun points off the starboard side above the railings, the tip of the barrel perhaps 8m above me.
I may have said it before, but its hard to beat a good armed trawler. All the engineering and armament are packed into a small, tough hull, just the right size to get round easily on a dive without excessive decompression, and no empty holds between the interesting stuff.
The next pair of divers arrive and I move on towards the stern, taking in the minesweeping gear and diesel generators, the remains of the helm and the boiler and engine, before coming to the smaller twin machine-gun platform on the quarter-deck.
A mixed shoal of pouting and poor cod parts as I drop below to the rudder and propeller. I look out into the barely noticeable current, and half a dozen big pollack look back.
Its easy to see why Mole Valley SAC selected this site; its the ideal club wreck dive. Shallow enough for nearly everyone, its also compact enough for a no-stop dive and yet has plenty to interest those wanting to make a longer dive.
Back on board, the other divers add a couple of details to my sketch - the remains of the funnel off the starboard side and the toilet inside the stern. There seems to be something about divers and toilets...
Although the Northcoates was the main objective of the weekend, we had begun the day on the wreck of the Cairndhu in equally nice surface conditions, though with dubious underwater visibility. Vernon had suggested leaving the Northcoates until low-water slack, predicting that we would have better visibility, and the two dives proved him absolutely right.
While HMS Northcoates was a casualty of WW2, the 4019 ton steamship Cairndhu was torpedoed by UB40 in April 1917 while carrying a cargo of coal from South Shields to Gibraltar.
We had descended through layers of clear, then murky, water to 29m, and a very grainy 4m or so of viz. The shot was just aft of the bow, but it had taken me the first five minutes of the dive to work that out, before following wreckage aft to the boilers and engine, then the propeller shaft to the stern.
The Cairndhu is listed in WW1 Channel Wrecks as carrying a 13lb gun, then in Dive Sussex as having a 4.7in gun bolted to the stern, with a howitzer located 10m off the stern.
I have to confess that I could find no sign of a gun or its mount on the stern, which is well broken, though I did find part of a steering engine which could easily be confused with a gun barrel. As for the howitzer, after 50 minutes on the wreck I just didnt have time to search off the stern for it.
Perhaps the gun sank into the soft silty sand, or perhaps it is buried beneath collapsed wreckage. Or maybe confused reports from years ago mean that it is 10m off the stern and the gun still on the stern is actually the steering engine. Any Cairndhu enthusiasts with the answers, let me know.
Skippers Vernon and Daniel work understandably well as a team, with a well-practised division of labour. Vernon has been running a boat out of Littlehampton for 30 years, previously My Joy, and when he wanted a new boat Daniel joined him as partner in Our Joy.
Come time to dive, Vernon is at the helm and Daniel does the deck work of throwing the shot and assisting divers. Back at Littlehampton, Daniel takes the helm to manoeuvre alongside the pontoon in the river, bringing the Offshore 105 into a tight space behind Michelle Mary, another of Littlehamptons longstanding dive boats.
I ask if this is connected with Daniels previous employment as a harbour pilot, but both father and son assure me that it just works out that way. In general, Vernon is at the helm for diving trips while Daniel is at the helm when anglers are on board.
Littlehamptons charter boats used to be based in the marina to the west of the river. Now most have moved to a new charter pontoon on the town side of the river below the Nelson Hotel, and a waterfront with a convenient selection of cafés and takeaways. What used to be a scruffy, part-derelict industrial harbourside has been developed into a promenade backed by des-res houses and apartments with a view of the river.
With Sundays start an hour later for the tide, I have time for an early morning stroll. I bump into Harbourmaster Colin Hitchcock, who shows me round the new harbour offices, complete with conference rooms which are available to dive clubs and schools for training.
Looking for something a bit different, the mornings wreck is the Ramsgarth, an unarmed steamship of 1559 tons that in November 1916 was boarded and scuttled by the crew of UB39. Vernon checks his notebook and it is an unbelievable nine years since he had last put divers on this wreck.
Its conveniently close to Littlehampton, so I have to ask: Is there something wrong with it He replies that divers simply dont request it that often.
On the way out, the sea is oily calm, though the sky has greyed over and there is a light drizzle. A black squall arrives just as I finish kitting up. Down at 29m again, the conditions are a little better than Saturdays high-water slack. Visibility is 6 or 7m but still very grainy.
The Ramsgarth turns out to be a very enjoyable little wreck. The stern is reasonably intact, with the port side uppermost. From the stern the propshaft leads forward, breaking for a few metres just aft of the engine. The forward part of the wreck has collapsed, with the boilers rolled out onto the seabed.
Then theres another small split before the bow, which is again reasonably intact, the port side uppermost and both anchors tight into the hawse pipes.
Back on Our Joy, the squall has passed and the sun is creeping out, though the wind is picking up from the south-west. An advantage of a wreck this close is that there is plenty of time to head back into Littlehampton for fills and to lunch on the waterfront. The mouth of the river Arun is inhabited by hordes of swans and I now learn why they like it here - its the endless supply of fish and chips, sandwiches and ice-cream.
After such nice conditions on Saturdays low-water slack, we opt to repeat a winning formula by selecting a wreck close to the Northcoates to finish the weekend. Next to it in Dive Sussex and about a mile away geographically, our choice is the Dutch steamship Zaanstroom.
The sea is picking up, and Our Joy slams as Vernon takes us cautiously west. I ask whether he would prefer a closer site but he is philosophical. Were tied to diving at slack water and have to wait for the tide to rise before we can re-enter the harbour, so we may as well dive the Zaanstroom as any other wreck.
The magic number all weekend has been 29m and it is no longer a surprise that the shot rests on pale sand at just that depth off the starboard side of the Zaanstroom.
This 900 ton ship foundered in December 1911, when water leaked into the cargo of china clay she was carrying from Fowey to Amsterdam.
Plenty of this can still be found in the holds, and as white streaks on the sand alongside.
Resting upright, the sides of the hull are rotted through in many places and the main deck has mostly collapsed. Unusual features are the fallen bodies of cargo-handling cranes located along either side of the holds, as opposed to the more common mast, winch and derricks that would have been positioned along the centreline of the ship.
At the stern, I get the impression that changing a propeller was treated as casually as changing a wheel on a car. There is a spare propeller and section of shaft, together with a ladder ready to drop over the side - and an enormous ring spanner.
With choppy surface conditions, slack water and little decompression to worry about, I take care to come back up the line. Daniel throws me a grabline and pulls me onto the diver lift at the stern. A ladder would have been manageable, but diver lifts just make life so easy.
In fact, the whole weekend has been nice and easy. Amid the general trend to dive more technically on deeper wrecks, I needed that reminding there are still so many good wrecks shallower than30m.

By the propeller of the Zaanstroom
a lobster guards its home in a pipe by the boilers of the Cairndhu
Poor cod and pouting by the Cairndhus propeller shaft
the base of the cargo-handling crane on the Zaanstroom
The gun at the bow of the Northcoates
Vernon & Daniel Parker aboard Our Joy


GETTING THERE: See the map on the Our Joy website, www.ourjoy.co.uk. Boats are berthed on the pontoon where the riverside road meets the seafront road, by the Nelson Hotel.
DIVING: Our Joy, 01243 553977 / 07850 312068. Other Littlehampton boats include Michelle Mary, 01903 739010; Defiant, 01903 739090; Voyager, 02087 867821; Copperhead, 01243 8411477; and Happy Hooker, 01903 771661.
AIR: Arun Nautique (air) 01903 730558. Ocean View Diving Services (air, nitrox & trimix) 01243 601000.
ACCOMMODATION: B&B at the Nelson Hotel by the charterboat pontoon, 01903 713358, www.nelsonhotel.co.uk.
FURTHER INFORMATION: Harbourmaster 01903 721215. Admiralty Chart 1652, Selsey Bill to Beachy Head. Ordnance Survey Map 197, Chichester and the South Downs, Bognor Regis and Arundel. Dive Sussex, by Kendall McDonald. World War One Channel Wrecks by Neil Maw. Mole Valley SAC, www.mvsac.org.uk.