The Penlee lifeboat, Ivan Ellen, heading out to tow a small boat that had lost power off Lamorna. This was snapped from a boat off Mousehole, looking across Mounts Bay towards St Michael's Mount.
The current Penlee lifeboat is a Severn class - the biggest in the RNLI fleet. Measuring over 55 feet in length (17 metres) and weighing more than 40 tons the boat is powered by twin engines that put out over 3,000hp. This means the lifeboat can hit a top speed of 25 knots, but this burns through around 1,000 litres of fuel per hour.
Severn class lifeboats are completely watertight and can self-right if capsised. This isn't a feature that is often called called upon, but it gives an idea of the conditions the boats are designed to handle.
On the bow of the boat is the identification number, in this case 17-36. The 17 is the approximate length of the boat in metres and the 36 tells us the Ivan Ellen is the 36th Severn class to be built. To buy a Severn class lifeboat will set you back well over £2 million.