The chance to dive two sites of historic significance was a dream come true for archaeology enthusiast Duncan Ross. So, when the opportunity came up to dive the HMS A1 submarine and the first HMS Invincible off southern England, he jumped at it. This is his report.  

I booked my place on the NAS protected wreck day late last year, and spent the interim doing a little research. I found a couple of books in a second-hand bookshop near my home in Birkenhead, near Liverpool: one about early submarines and another on 18th century ship construction. Where they will go on my overloaded maritime archaeology bookcases I have no idea.

With any British dive plan, you pray for good conditions. When the day came, we hit a heatwave.


The A1 was the British Royal Navy’s first British-designed and British-built submarine, having been built at the Vickers yard in Barrow-in-Furness, north-west England, in 1902. She also holds the dubious accolade of being the first British submarine tragedy. In fact, she wrecked twice. All hands were lost when the mail steamer SS Berwick Castle struck her conning tower in 1904 as it passed above. She was eventually raised, and the bodies of the crew buried. She was then put back into service under a young Max Kennedy Horton, future admiral and commander-in-chief of the Western Approaches during the Second World War. Her eventual loss occurred in 1911 during training while being piloted automatically, and no lives were lost.  The wreck now sits twenty minute’s boat-ride from Eastney beach, Hampshire, UK, at a depth of around 12 metres.

The A-class submarines had a chequered track record. They were the next step after the original the Holland class, and design ideas were still being tested—sometimes at the price of human lives. How men were recruited to crew them is mystifying: perhaps it was higher wages, a spirit of adventure—or simply in a time when dangerous occupations were more commonplace.

The Dive

We set out from Eastney slipway at 8.30am in the NAS’s own rigid inflatable boat (RIB) under the guidance of Mark Beattie-Edwards and A1 licensee Martin Davies. The young lad in me can’t help feeling a bit ‘James Bond’ when setting out on a RIB: the post-dive clamber back aboard, huffing and puffing, with legs flailing – not so much.

We arrived over the site with plenty of slack tide and begin kitting up. A1 can be a little tricky to locate, but after a little exploring we dropped the shot line, and Martin Davies descended to check it was close to the wreck.

Image: Mark Beattie-Edwards at the helm of the NAS Dive Club's RIB "Honor"(Duncan Ross)

A good portion of the wreck is buried under the seabed. Her bow is clear, however, and points slightly upwards, allowing a little room to swim under. The torpedo hatch and mechanism are visible, carpeted with anemones. The rectangular torpedo loading hatches are visible along the fore part of the hull, and one of the missing hatch covers can be seen on the seabed. Tompot blennies are prolific and can be seen everywhere, peering from beneath rusted and anemone-coated iron. Shimmering schools of bib circle the periphery, vanishing with the flash of a torch.

Image: The torpedo loading hatch (Duncan Ross)

The conning tower—the last of many modifications—is intact, although a large split has opened up in the rear side, and there are several holes (possibly originally viewing holes) through which a diver can spy curious sea life. The outer hatch is missing, allowing a tantalising view inside. After its fatal collision in 1904, an extra outer hatch was fitted to the A1–an addition which then became standard in future submarine design.

Image: The conning tower (Duncan Ross)

The stern portion of the hull is virtually hidden in the seabed, and a little further along a circular feature (thought to be an old buoy) sits in the sand. My dive partner and I enjoyed a 30-minute dive on this important piece of maritime history, and could easily have stayed longer. But, there was more to do: after a quick break at NAS HQ in nearby Fort Cumberland, Portsmouth, we had lunch and a presentation from Martin Davies about the history, features and future of A1. We then changed our cylinders headed to the barge Avon for the day’s second dive.

Image: Safely back at the surface after our dive (NAS)

HMS Invincible

HMS Invincible began life as the French 74-gun ship-of-the-line L’Invincible, but was captured by the British at the First Battle of Cape Finisterre. She was put into service in the Royal Navy as a third-rate ship of the line until her sinking in 1758, fully laden and bound to fight the French in modern-day Nova Scotia, Canada.

At the time of Invincible’s capture, British warship innovation was lagging behind. The Royal Navy recognised her highly advanced construction, and soon incorporated her into the fighting fleet. Indeed, she represents a crucial paradigm shift in ship construction: at the 1805 battle of Trafalgar, three-quarters of vessels were of similar design.

Thankfully there was no loss of life when HMS Invincible became stuck on the Solent’s Horse and Dean Sand. But many would have died attacking and defending her during her fighting life: if not a war grave, then she is a sunken battlefield of sorts.

Image: HMS Invincible as drawn by John Charnock between 1747 and 1748 (

The wreck of HMS Invincible was discovered in 1979 in the eastern Solent waterway between Hampshire and the Isle of Wight in the southern UK, when local fishermen snagged it with their nets. Since then several phases of excavation have taken place, initially by John Bingeman (Licensee 1980 – 2010) and more recently by current licensee Dan Pascoe, sponsored by MAST and Bournemouth University. In recent years, shifting sands have prompted a phase of emergency excavation.

The Dive

Descending the shot line to a very accessible 8-metre depth, my buddy and I were immediately amongst the wooden wreckage and an underwater excavation in progress – the first I had ever seen. Scaffolding grids, tools and sandbags surrounded us, and in our periphery commercial divers went about their tasks. One of the first things noticeable was the surprising depth of some of the excavation trenches. Finning up and over the scaffolding grid I dropped down at least a metre into part of the hull and could see structural features. Invincible was constructed using 200 wood-clad iron knees, possibly due to wood shortages in Europe.

Image: A wood-encased iron knee on the wreck of HMS Invincible: the nails on the panelling look as if a French boatyard worker had driven them in only yesterday (Duncan Ross)

Although guidelines ran throughout the site, we quickly became disoriented. But there was so much to see that this did not lessen the experience: every direction yielded new features. The day before the dive, I had taken a tour around HMS Victory in Portsmouth to gain an impression of a warship from the age of sail. To think that the wreck of Invincible is of a similar size is mind-blowing. Dan Pascoe said the site is around 50 metres in length.

Image: Some of HMS Invincible’s remarkably preserved decking lies tilted at around 45 degrees (Duncan Ross)


The sheer amount and preservation of artefacts and ships timbers is astounding. Just days before we arrived, the team had uncovered the shot locker with a horde of cannonballs and several small concreted swivel guns. This was my favourite area: like a scene from the Alien films, dark orbs littered the seabed, some broken free by the archaeology team and others still concreted together.

Image: Cannon balls on HMS Invincible (Martin Davies)

“Feel free to pick some up,” we were told during our pre-dive briefing—so long as we put them right back. The cricket-ball-sized ones were tricky enough to lift, not to mention the bowling-ball-sized ones, and to think sailors had to carry these up to the gundeck. The thought of one being fired at the speed of sound toward another ship is unimaginable. The firepower needed to propel projectiles of this size and weight was colossal. A full broadside would have been quite a thing.

Amongst the concreted mass of cannonballs were two remaining swivel guns—the others having been excavated already. One was partially excavated, with the first reinforce and cascabel clearly showing. The other had only the chase and muzzle visible beneath a solid layer of light grey concretion. Historical documents state that all the guns were salvaged from Invincible as she foundered on the sands in 1758, so this was a great surprise. Dan explained that these deck guns would have been stowed away until needed.

Image: This excavated swivel gun from HMS Invincible will need four years of conservation to stabilise it (Duncan Ross)

Other artefacts from the wreck, including bottles and a square wooden meal plate, can be viewed in the Museum of the Royal Navy in Portsmouth Historic Dockyard. The excavation team also hold periodic open days where a range of other finds can be viewed: the next is scheduled for 22 September in Poole, Dorset, UK. Current funding for the HMS Invincible project has open up the excavation experience to war veterans: we briefly spoke to two former military divers who were clearly enjoying the work. Long may the funding continue!

There may have been abundant sea life amongst the wreckage of Invincible, but I was so engrossed that, if there was, I sadly missed it. My only encounter was when I reached out to touch what I thought was seaweed waving in the current: as my fingers connected with the fluttering object, a cuttlefish shot away, startling me.

A one-hour bottom time flew by, and I could have stayed much longer on what was one of the most unique dives I have experienced. What a day. And all for £40, if I remember rightly. Travelling down from my home in Liverpool obviously incurs extra cost, but it was worth every penny. I will certainly sign up again next year if possible.

Image: Happy divers aboard Avon (NAS)

Further Reading

John Swinfield’s book Sea Devils, Pioneer Submariners details the fates of many of the A-class submarines, including A1.


The following link gives an excellent interactive 3D view of the wreck of the A1, plus lots of information,

pictures and video


The following link is an excellent source of information on HMS Invincible, using state-of-the-art technology to

virtually take you amongst the wreck


Edited by John Cooper

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