ALTAIR - Cornwall & Devon

The Altair, or what’s left of her, lies deep off the Cornish coast. We’ve always had a soft spot for deep, historical wrecks, and this old steamship, torpedoed in 1917, delivers a proper challenge. Dropping onto her deck at 52 metres, the sheer scale of the 79-metre hull becomes apparent, even if she’s broken in places. Visibility here can be tricky, often just a few metres, so a good light and excellent buoyancy are essential. What we love about the Altair is the raw history of it all. You can trace the lines of her two boilers, still largely intact, and imagine the compound expansion engine that once drove her single shaft. The metal work is draped in dead man’s fingers and bright orange cup corals, with conger eels peering from every crevice. Our favourite approach is a slow circumnavigation, taking in the bow and stern sections, then spending some time examining the engine room remains. It’s a dive for experienced deep divers, demanding careful planning and gas management, but the rewards are tangible – a quiet, powerful connection to a moment in time. Expect to share the space with inquisitive pollock and shoals of pouting darting through the superstructure.

Location
Cornwall & Devon, United Kingdom, Mediterranean & Europe
Coordinates
50.517216, -5.284365
Type
wreck
Maximum Depth
52m

Wreck History - ALTAIR

Year Sunk
1917
Vessel Type
cargo ship
Cause
torpedo
Tonnage
2,586 GRT

The S.S. 'Altair' was a veteran of the seas, built in 1884 as the 'Hindustan' and sailing for over three decades before meeting a violent end during the height of World War I. On October 18, 1917, while steaming in ballast from Rouen, France, to Cardiff, Wales, she crossed paths with the German submarine UC-51. Without warning, a torpedo struck the unarmed steamship, sealing her fate. The 'Altair' sank quickly, becoming another casualty of the unrestricted submarine warfare that defined the era.

Today, the 'Altair' lies at 52 meters in the English Channel, placing her firmly in the realm of technical diving. The depth and strong currents demand respect, experience, and proper gas planning. For those qualified to make the descent, the wreck is a magnificent time capsule. Divers can explore the remains of the 19th-century vessel, including her two large boilers and compound expansion engine, which stand proud on the seabed. The structure is a poignant reminder of the Great War's toll on merchant shipping, now serving as a challenging and rewarding deep dive site off the English coast.

Marine Protected Area: Kelsey Head

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 ALTAIR

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 ALTAIR

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