Birthday Raid

The Birthday Raid also known as the Kumamoto Raid, was the first Allied air raid launched against the Japanese Home Islands. It was executed on April 29th, Emperor Hirohito's Birthday, against the major city of Kumamoto. It was meant to demonstrate increasing Allied air dominance, boost morale while lowering that of the enemy, and test Japanese defences.

Following the successful Guangxi Campaign roughly 50% of China outside Manchuria was in Allied hands. This allowed the construction of airfields from which strategic bombers could reach the Japanese Home Islands. RAF officer Arthur Harris was designated by AFEC air commander Albert Kesselring to begin planning the raid in February 1943. The date of the Emperor's birthday was chosen for its immense propaganda value. A mixed group of British Lancaster and German He 177 bombers were to be escorted by Beaufighter and Me 410 heavy fighters to their targets in Kumamoto.

At dawn on April 29th, the "Harris Group" took off from airfields around Wenzhou and rendezvoused at a set of islands offshore before beginning their flight towards Japan. With nearly all major Imperial Navy ships engaged in combat duties elsewhere, the raiders were not spotted as they crossed the East China sea northeast. A small merchant reported seeing planes, but this was dismissed by Japanese high command as being related to the fighting south of Shanghai. After four hours of flying time, the group sighted Kyushu and assumed their combat formation.

As the planes gained altitude in a bay west of their target, Kumamoto, they were finally definitively spotted. A squadron of Oscar fighters were sent to intercept the raiders. Harris Group's fighters moved to protect the bombers as they approached the city and began to be fired on by AA batteries with two bombers being hit and going down. Thirty-one bombers released their payload in roughly the correct area, but an incorrect report of overwhelming Japanese fighters caused the rest to drop theirs early. As the group turned about to return to China it was attacked with a running aerial battle ensuing. Although far superior in maneuverability, the lightly armed and armoured Oscars were driven off repeatedly by intense defensive fire from the bombers. Allied heavy fighters struggled to catch up with the Japanese fighters, but manged to down a couple with well placed cannon shots. Five bombers were shot down by Oscars by the time they broke off and returned to Japan, having run low on fuel. On the way back to China two He 177s would develop severe engine trouble and be forced to ditch, highlighting the design's problematic performance. By the afternoon, Harris Group had returned to its airfields in China, having lost seven bombers and two fighters to enemy fighters.

In the Allied press the raid was hailed as a massive success. Indeed it had suceeded in numerous respects. It showed the weakness of Japanese air defences around the Home Islands and how spread thin the IJN had become. Tactics and the performance of aircraft had been tested, resulting in numerous improvements before the beginning of sustained Allied bombings in 1944. In terms of propaganda it was a huge win for the Allies. The course of the war was shown to be going in the Allies' favour, as now they could strike at Japan itself and avenge their own losses. There was little long term strategic effects, however, as the raid was too small and inaccurate to do much lasting damage to Kumamoto's industry. Perhaps the only lasting effect was more resources put into Home Island defence by Japan, although this would happened in any case when sustained bombing began.