In the annals of warfare mass disappearances of soldiers and their equipment are rare but are on record. In the 18th Century during the Spanish War of Succession, 4,000 were reported to have disappeared, together with their weapons and equipment (horses included). In 1885, about 600 French colonial soldiers disappeared near Saigon, French Indo-China, without a trace of them nor their equipment. On August 21, 1915 soldiers of the New Zealand Army Corps' First Field Company signed sworn statements that they say the One Fourth Norfolk Regiment disappeared in an unusually thick brown cloud which seemed to move and rose upward and vanished. There were no traces of the regiment nor their equipment. No explanation can be found in the historical records of the Imperial War Museum archives. In 1939 over 2,900 Chinese Nationalist troops were reported missing from their camp, just south of Nanking. Again, men, equipment, guns, were missing though camp fires and mess tents were undisturbed. During the pacific campaign, there have been instances where whole platoons and larger units seem to have disappeared without any sign of combat or a struggle. Men, equipment, weapons -- vanish without a trace. In all instances the disappearances occurred in tropical climate and in the heat of battle or near combat zones. Missing aircraft, pilots and crew, are of special concern to the military when no explanations fit the usual reasons outside of combat. One such incident is the disappearance of a flight of five U.S. Navy TBM-3 Avenger torpedo bombers from Naval Air Station Fort Lauderdale (Florida) on 5 December 1945. While no explanation as to why navigation instruments could have failed all at the same time, and efforts to save the 14 crewmen were unsuccessful, it is believed that Flight 19 encountered a phenomenon of celestial nature. The last known radio transmission from the instructor pilot was heard by a ham operator. "Don't come after me ... they look like they are from outer space ... I'm at 2,300 feet. Don't come after me." After one of the most intensive air-sea rescue operations in U.S. Navy history, the Naval Board of Inquiry said, "We were not able to make even a good guess as to what happened."