or air search radar at the war's outset in September 1939. Not until January 1941, when a Japanese naval technical mission arrived in Germany, did the IJN learn that European nations were using pulsed radar for combat purposes. In August that same year, the Navy Ministry initiated a crash plan to speed up radar development, resulting in (among others) the Type 21 and Type 13 air search radars. Prior to completion in 1944, Taihō was fitted with two Type 21 air search radars, one mounted atop the island on the anti-aircraft control platform and one on the lower bridge deck at the aft end of the island. She also had one Type 13 air search set installed with an antenna mounted on the signal mast above the bridge. The Type 21 had a maximum effective range of while the Type 13 had a range of Aircraft Taihōs planned air complement varied considerably throughout her design and construction. Initially, it was envisioned she would carry 126 aircraft (with 30 of these in reserve). Later, this was pared down to 64, raised again to 78 and finally reduced to 53. One reason for the discrepancy in numbers was (in sharp contrast to the United States) the Imperial Japanese Navy's lack of insistence that its carrier planes have the smallest possible folded wingspan (many designs' folded only near the tips, while the wings of the Yokosuka D4Y Suisei dive-bomber did not fold at all). Her aircraft capacity was also changed based on previous wartime experience and the fact that Taihō was expected to carry larger newer-model carrier planes still under development at the time of her construction: 24 Mitsubishi A7M2 Reppu "Sam" fighters, 25 Aichi B7A2 Ryusei "Grace" torpedo-dive bombers and four Nakajima C6N1 Saiun "Myrt" reconnaissance planes. As none of these types were available at the time of her commissioning, Taihō went to sea with older-model aircraft. Prior to 13 June 1944, Taihō carried 65 aircraft: 22 Mitsubishi A6M5 Reisen (Zero) fighters, 22 Yokosuka D4Y1 Suisei "Judy" dive bombers (of which four were the D4Y1-C reconnaissance types), three Aichi D3A2 "Val" dive bombers and 18 Nakajima B6N2 Tenzan "Jill" torpedo bombers. By 19 June 1944, however, the day the Battle of the Philippine Sea took place, she had already lost nine aircraft due to various causes and had just 56 planes remaining for actual combat. Service history Battle of the Philippine Sea