A few notes on the firebombing of Okayama: As became the standard pattern, on this bombing run, the 21st Bomber Command set out to destroy four Japanese cities simultaneously. https://twitter.com/jacremes/status/1277285634063859714

Including Okayama, the B-29s taking off from the Mariana Islands brought destruction and death to Sasebo, Moji, and Nobeoka. Here’s a map - from the Command’s Tactical Mission Report 234-7 - showing routes to and from the targets.

This was the 3rd of 16 bombing runs that destroyed most of Japan’s smaller cities between mid-June and the penultimate day of the war. Here’s a map showing the results of burning 63% of Okayama’s built-up area (2.13 square miles).

Even with the “success” of the incendiary bombing of Japan’s large cities that began in earnest in March ‘45, the AAF continued to fine tune how to best incinerate urban Japan.

Mission 234 to Okayama stands out in this regard, when 138 planes dropped 980 tons of incendiaries on the city. Okayama was the first set afire with a new type of incendiary bomb, deemed superior “for use against typical Japanese structures” than the standard M-69 incendiary.

Also, ensuing B-29s met so much turbulence/smoke due to fires raging below that they had difficulty releasing their own incendiaries. The Command made note and changed bombing altitude for subsequent cities to be destroyed. Here’s a (poorly digitized) photo of Okayama aflame.

The Tactical Mission Report from which I got this info, along with the TMRs for every other firebombing raid that the 21st Bomber Command carried out against urban Japan, is at http://japanairraids.org , the digital archive that @dfedman and I maintain.