Historical Document · 2018
A CBI SIGABA Near-Miss
Hengyang airstrip evacuation, May 1944; rotors lost in the river (2 pp.) [writer A]
Historical Document · 2018
Hengyang airstrip evacuation, May 1944; rotors lost in the river (2 pp.) [writer A]
A CBI SIGABA Near-Miss October3 The Enigma machine, used by the Germans so frequently in World War II (19391945), is famous for a simple reason—it did not work, at least not to the extent that the Germans hoped it would. In contrast, the U.S. SIGABA, a contemporary of the Enigma, is still relatively unknown to this day for the opposite simple reason— it did work. The SIGABA was an advanced cipher machine jointly developed by the Army (who called it SIGABA) and the Navy, who called it Electric Cipher Machine (ECM). There is no credible evidence that it was broken by any nation during the war. Yet there were scares aplenty involving that SIGABA. Some of us are familiar with the 1945 Colmar (France) Incident, in which a truck carrying a SIGABA and related materials disappeared. The missing SIGABA and materials were all found intact later on. The CCH has elaborated on this incident in the past. CCH is now reporting another SIGABA near-miss incident—a first-heard for us actually. The incident happened in the The SIGABA machine. China-Burma-India (CBI) Theatre in May 1944. Japan had invaded China in 1937; when the Allies, i.e., the Americans and British joined with the Chinese, the area was termed the China, Burma, India Theater of War. Japanese attacks forced the Chinese government to relocate to the southwestern portion of China, bordering India and Burma. The Japanese, in an attempt to compel China into surrendering and to evict the British from Southeast Asia, invaded Burma, also separating British India and China. The Allied goal became to reconnect the two, either by road or by air. Since China tied down thousands of Japanese troops, it was imperative that China continue the fight against Japan and constant resupply from India was a necessity for this. Initially, U.S. Army Air Force planes kept up this supply by flying materiel in over the Himalayas. The theater saw savage jungle fighting and massive air operations, with ultimate Allied success. In early May 1944, the Japanese were attempting to take the Chinese city of Hengyang* and the nearby U.S. 14th Army Air Force airstrip, just across the Xiang River.** Personnel at the airstrip were alerted, prematurely it turns out, that a Japanese paradrop had already happened and that the Japanese were deploying around a nearby field. In light of this, code room personnel decided to evacuate and join up with some Chinese forces in Hengyang. In the frenzy and excitement, no one thought of destroying the SIGABA machines or other cryptographic systems. One-quick thinking team member though did grab a set of SIGTELP rotors and ran to the river with the rest of the men. Unfortunately, they crowded into a sampan river boat, which did not make it across. It capsized, drowning the man carrying the rotors. The rotors were never recovered. We remember this story because of the unsung hero who lost his life protecting cryptologic materials. For the record, CCH has never heard of a SIGTELP rotor and has been unable so far to link it to the SIGABA (no CCH reference on the SIGABA mentions a SIGTELP). The source for this story is the Office of the Theater Signal Officer, India Burma Theater. Interestingly, the Office mentions another SIGABA compromise scare but, unfortunately, does not elaborate. * The Hengyang campaign, ending in Japanese victory, was June-August 1944. ** The source says the Yellow River but that is farther north. The Xiang River is more likely. Sources: Unclassified Battle of Hengyang background materials; CCH source files (Office of the Theater Signal Officer, Colmar background materials); “The Sigaba/ECM II Cipher Machine “A Beautiful Idea,”” by Tim Mucklow (CCH Publication)