Able was planned to take surveys of the landing beaches with X20, commanded by Lt KR Hudspeth, spending four days off the French coast. Periscope reconnaissance of the shoreline and echo-soundings were performed during daytime. Each night, X20 would approach the beach and 2 divers would swim ashore. Soil samples were collected in condoms. The divers went ashore on two nights to survey the beaches at Vierville-sur-Mer, Moulins St Laurent and Colleville-sur-Mer in what became the American Omaha Beach. On the third night, they were due to go ashore off the Orne Estuary (Sword Beach), but by this stage fatigue (the crew and divers had been living on little more than benzedrine tablets) and the worsening weather caused Hudspeth to shorten the operation, returning to Dolphin on 21 January 1944. Hudspeth received a bar to his DSC. X20 and X23, each with a crew of five, acted as navigational beacons to help the D-Day invasion fleet land on the correct beaches (Operation Gambit), as part of the Combined Operations Pilotage Parties (COPP). The craft were also equipped with a radio beacon and echo sounder to help direct Canadian and British ships to the suitable positions on Sword and Juno beaches. Oxygen bottles on both craft enabled the crews to remain submerged for extended periods during this operation, 64 hours of the 76 total hours at sea. Legacy The only remaining intact example of an X-Craft, X24, was transferred from HMS Dolphin, where she had been on display since 1981, to the Royal Navy Submarine Museum nearby in 1987. Operations continued in the Far East with the revised XE class submarines. X-craft and crews X3 – unofficially named Piker 1, was lost on 4 November 1942 in Loch Striven due to a leaking engine valve. All crew escaped by utilizing their Davis Submerged Escape Apparatus. X5 – unofficially named Platypus, commanded by Lt. Henty-Creer RNVR (also the operation's commander), crew S-Lt. Nelson, Midshipman Malcolm, and ERA Mortiboys; passage crew Lt Terry-Lloyd (commanding), L/S Element, Stoker Garrity. Henty-Creer, Nelson, Malcolm, and Mortiboys were killed in the attack, though X5's exact fate is unknown. X6 – named Piker II, commanded by Lt. Donald Cameron, crew Lt. J. T. Lorimer, S-Lt. R. Kendall, and ERA Goddard; passage crew Lt Wilson (commanding), Leading Seaman McGregor, Stoker Oxley. Cameron earned a VC, Lorimer and Kendall DSOs, Goddard a Conspicuous Gallantry Medal. X7 – unofficially named Pdinichthys,