27th March 1918
Western Front
Germans advance on both side of Somme in night attack, reaching Sailly le Sec (12 miles from Amiens), but lose ground in British counter-attacks. Germans afterwards fail in attacks from Bucquoy to Rosieres and are checked near Lassigny and Noyon, but take Montdidier after rapid advance.
Naval
Royal Navy destroyer
HMS Kale accidentally hits a British mine, causing it to sink with 41 lives.
Aviation
Ship Losses:
Allendale (United Kingdom) The cargo ship was torpedoed and sunk in the Atlantic Ocean 52 nautical miles (96 km) south by west of The Lizard, Cornwall (49°50′N 5°50′W) by
SM U-101 ( Kaiserliche Marine with the loss of a crew member.
Beira (Portugal) The sailing vessel was sunk in the Atlantic Ocean (34°10′N 14°35′W) by
SM U-154 ( Kaiserliche Marine). Her crew survived.
Carlo P. (Italy) The sailing vessel was sunk in the Mediterranean Sea 30 nautical miles (56 km) north of the Galite Islands, Tunisia by
SM UC-54 ( Kaiserliche Marine).
Castrenzo Coppola (Italy) The sailing vessel was sunk in the Tyrrhenian Sea off Naples by
SM UC-53 ( Kaiserliche Marine).
HMS Kale (Royal Navy) The E-class destroyer struck a naval mine and sank in the North Sea.
Watauga (United Kingdom) The schooner was shelled and sunk in the Atlantic Ocean 450 nautical miles (830 km) west by north of Lisbon, Portugal (38°54′N 18°24′W) by
SM U-155 ( Kaiserliche Marine) with the loss of five crew.