HMSM UPSTART - Cornwall & Devon

The HMSM Upstart is one of those wrecks we keep coming back to. Sitting upright at 37 metres, she’s an easy dive on a calm day, though that depth means some current can really make it a workout. Built in 1942, this U-class submarine was scuttled in 1957, so she’s been down there a while and the sea has really claimed her. We love finning along her deck, spotting the periscope tubes and the outline of her conning tower. The bow torpedo tubes are a particular favourite – you can usually see conger eels peering out, their thick bodies disappearing back into the dark. Look closely for dogfish eggs tucked into crevices and always keep an eye out for curious seals. If you hit it right, with good visibility and slack water, it’s a genuinely atmospheric dive, a real window into naval history and the power of the ocean to reclaim what’s hers. This isn't a site for beginners; that depth and the potential for current mean you want to be comfortable with your diving.

Location
Cornwall & Devon, United Kingdom, Mediterranean & Europe
Coordinates
50.506893, -1.546573
Type
wreck
Maximum Depth
37m

Marine Protected Area: Tennyson

Best Time to Dive in Cornwall & Devon

The warmest water temperatures in Cornwall & Devon occur in January, averaging 9.6°C. The coolest conditions are in December at 9.6°C.

Monthly Water Temperatures

  • January: 9.6°C (air: 7.3°C)
  • February: 9.6°C (air: 8.4°C)
  • March: 9.6°C (air: 8.6°C)
  • April: 9.6°C (air: 10.1°C)
  • May: 9.6°C (air: 12.6°C)
  • June: 9.6°C (air: 15.2°C)
  • July: 9.6°C (air: 16.6°C)
  • August: 9.6°C (air: 17.1°C)
  • September: 9.6°C (air: 15.9°C)
  • October: 9.6°C (air: 13.5°C)
  • November: 9.6°C (air: 10.7°C)
  • December: 9.6°C (air: 8.7°C)

Nearby Dive Sites in Cornwall & Devon

Nearest Dive Centres to HMSM UPSTART

Marine Life in Cornwall & Devon

Home to 192 recorded species including 93 reef fish, 18 sharks & rays, 13 whales & dolphins, 11 crabs & lobsters, 11 other, 10 seagrass & algae.

Notable Species

Recommended Packing List for HMSM UPSTART

Based on average water temperature of 9.6°C.

  • Drysuit - water at 10°C demands a drysuit with thermal undergarments
  • Hood & Gloves (7mm+) - critical to prevent heat loss
  • Mask - essential for every dive
  • Fins
  • BCD - buoyancy compensator
  • Regulator - your most safety-critical piece of gear
  • Dive Computer - tracks depth, time, and NDL
  • Surface Marker Buoy (SMB) - essential for boat pickups
  • Dive Torch - useful for crevices and colour at depth
  • Underwater Camera - capture your diving memories

Frequently Asked Questions

What is the maximum depth divers can expect when exploring the HMSM UPSTART wreck?
The maximum depth divers can expect when exploring the HMSM UPSTART wreck is 37 meters. This depth classifies it as an intermediate dive, suitable for divers with appropriate training and experience.
What are the key features and marine life divers typically encounter on the HMSM UPSTART submarine wreck?
The HMSM UPSTART is a substantial submarine vessel, measuring 60 meters long and 4.9 meters wide. Divers can look for its distinctive features, including a 3-inch deck gun and four 21-inch torpedo tubes. Information regarding specific marine life encounters is not provided in the available data.
What diving certifications are required to dive the HMSM UPSTART, and is it considered a difficult dive?
The HMSM UPSTART is classified as an intermediate difficulty dive. While specific certification requirements are not detailed, divers should possess the necessary experience and training for dives to 37 meters on a wreck. Given its classification as a "Dangerous wreck," advanced wreck diving training is highly recommended.
When is the optimal season or time of year to dive the HMSM UPSTART for the best visibility and conditions?
The provided data does not specify the optimal season or time of year to dive the HMSM UPSTART for best visibility and conditions. For general guidance on diving conditions in the region, you might consult our When to Dive section.
What are the typical current conditions and visibility like at the HMSM UPSTART dive site?
Information regarding the typical current conditions and visibility at the HMSM UPSTART dive site is not available in the provided data. Divers should always check local dive reports and consult with experienced dive operators in Cornwall & Devon before planning their dive.
Are there any unique historical aspects or specific parts of the HMSM UPSTART wreck that divers should look out for?
The HMSM UPSTART, a submarine built in 1942 by Vickers Armstrong, was deliberately sunk on July 29, 1957, for use as a sonar target. Divers can explore its impressive 60-meter length and look for key features such as its 3-inch deck gun and four 21-inch torpedo tubes. Its history as a purpose-sunk vessel adds a unique dimension to the dive.