The Bulgarian balloon observers also took part in the war. They were most active on the Dobrudzha Front, where aircraft activities were scarce (a German bomber squadron, flying missions against Bucharest and Constanţa: "Gotha" bombers accounted for the most flights). Near the Bulgarian city of Yambol an airship hangar was constructed to house German airships. The airship Schütte-Lanz SL 10 was the first to use it. According to documents of the time it was assigned to the Bulgarian Army, but was actually under German control. It was lost during a flight over the Black Sea in July 1916. In August 1916 the LZ 101 replaced it. After performing raids on targets in Romania and Greece it returned to Germany in August 1917. In November 1917 the naval airship L 59 arrived. That airship flew a series of remarkable missions, such as an attempted resupply of the garrison in the colony German East Africa and the bombing of Naples and Port Said. During a mission against the British naval base in Malta, a lightning strike over the Mediterranean Sea set it alight and completely destroyed it. All hands were lost.