My understanding is that the US unit, the 509th Composite Group, did various training runs to practise for the A-bomb drops.
Did the Japanese ever notice the training runs? Speculate what they were doing? Try to intercept them?
IIRC there was in an article about the first atomic bombing that the Japanese ignored the aircraft because it was a single plane, very high up, so they assumed it was just doing photoreconnaissance. Their problem at the time was a huge swarm of bombers low enough to hit places accurately or carpet bomb an area.
By mid-1945, the Japanese had all but lost control of their airspace, especially for high-altitude pursuit of bombers. Which, as md2000 notes, were assumed to be recon, not attack planes.
Cool story, bro:
Many years ago, I worked for Mitsubishi in Japan. One day, we had to go to the main headquarters of our division, so we piled into a car for the ride. On arrival, I made note of how long-and wide-the driveway up to the building was, at which point everyone got quiet. After a few seconds, my boss explained in a halting manner that it was originally a landing strip where, prior to the US entry into WWII, pilots would practice " flying very low over a nearby lake."
I turned to the guys in the back in time to see them attempting to suppress their shit-eating grins.
//CSB
The US had been flying sorties over Japan for weeks before the actual nuclear bombings. Some were just weather and photo recon missions. Others were actual test bomb drops. So by the time actual missions took place, the Japanese were not paying attention.
The actual missions consisted of four aircraft: a weather scout aircraft that preceded the main group by an hour, and the bomber, a photo recon aircraft and a a blast instrumentation aircraft.
If observers in Japan had been super-alert, they might have wondered why planes dropping the test bombs were then peeling off at extreme angles and speed to get the hell away as fast as possible.
Given the effects of carpet-bombing of Tokyo and other cities, it’s not surprising that Japanese leaders had other preoccupations.
This is something I recall wondering about from when I was kid reading of the atomic bombings, mainly unarmed (tail gun only) unescorted small number of B-29’s, seemed risky.
However as mentioned F-13 photo recon B-29’s had operated over Japan regularly since November 1944 and proved hard for Japanese fighters to intercept, flying higher than bomber formations and able to go to full speed to escape, unlike formations.
And by August 1945 the Japanese were no longer always intercepting even daylight bomber formations. The 20th AF flew a series of different daylight raids on Jun 22 and again Jul 24 with no direct support from 7th Fighter Command a/c on Iwo Jima, which went after their own separate targets, and even when weather prevented scheduled escorts like on Jun 15, negligible losses resulted from the B-29’s proceeding alone. Most B-29 bombing in the period was still at night but it was reaching the point where the main advantage of flying at night was reducing flak effectiveness as day fighter interception dwindled. The Japanese were saving remaining fuel, a/c and pilots for the expected invasion.
OTOH John Toland’s ‘The Rising Sun’ contained a first hand account of rumors in Hiroshima of an atomic bomb attack before the raid (though it’s not clear if they were limited to Hiroshima). It doesn’t seem inconceivable the Japanese could have gained more specific forewarning, though in the actual case Japanese intelligence about US moves after the start of the war wasn’t generally good (they had a very good idea of US order of battle in various places at the start of the war, but much less so as the war progressed, and nothing to compare to the advantage the US gained with code breaking).
Was that actually done anywhere within observation range of the Japanese? I thought it was done over the ocean and isolated (if not uninhabited) islands and atolls. Given how weak the Japanese were in the islands at that time, not sure how the intel would make it back to them.
Even if it did… what sense would it make?
What’s funny is that Tibbets and the other pilots actually wore out a whole squadron of B-29s practicing the maneuvers - wore out to “no further flight status” in some cases, IIRC. Enola Gay and Bock’s Car were brand new craft.
Bizz, I’m not getting this. What did the guys in back think was funny?
Dennis
Same question here.
Practicing for Pearl Harbor?
FWIW, here’s some info about the combat uses of the pumpkin bombs (Fatman simulations) over Japan.
The Japanese gave up entirely on sending fighter missions against small groups of US bombers towards the end of war, and barely did anything against large groups. They were conserving their fighters for the expected invasion.
So LeMay had some of the guns taken out of the bombers to conserve weight.
The stories from Hiroshima survivors is that the air raid sirens went off when the Enola Gay, et al., group showed up but then the all clear sirens rang indicating to real raid was expected due to the small size of the group. Ordinary people thought it was just s weather survey which were common.
The dive and turn in the practice runs doesn’t seem to have attracted any attention. No info about the Hiroshima raid: number of planes, incoming altitude, etc., seems to have gotten thru to anybody to make any effect on the air defense folks at Nagasaki (where there were multiple bomb runs due to clouds).
My guess was practicing for kamikaze missions.
Before the US entered the War?
I’m pretty sure the anecdote is a reference to Pearl Harbor.
Did the 509th ever do this over Japan prior to the 6th of August? From memory, the discussions of the trajectory were still being kicked about by Tibbets and Serber hours before the final takeoff. Which isn’t quite to suggest that the manoeuvre hadn’t been done over Japan. But one would like some specific evidence.
No, dropping torpedoes for Pearl Harbor.
The Japanese may not have noticed the training runs, but they may have noticed some of their cities not getting carpet bombed. I recall reading that Hiroshima and others were purposely avoided to “save” them for the big show. Not just for the maximum psychological shock of a city destroyed by a single explosion, but also to measure the results without any noise from other bombardments.
Sorry, forgot the link from my previous post. Here it is: combat usage of the pumpkin bombs.
This.
Richard Rhodes tells the story very well in Making of the Atomic Bomb, but in short - Mitsubishi was tasked with building torpedo bombs that would work in the shallowness of Pearl Harbor. The standard design dived as deep as 50-60 feet before coming back to the surface and beginning the powered attack run. Pearl was too shallow for that, so they had to be redesigned for less water penetration, and some of that was pilot training. I’d never heard of the test facility described above, but it makes sense.
Mitsubishi barely finished the design and engineering in time to produce the bombs and get them to the fleet for the sortie to Hawaii.
The factory is in Nagasaki.
The practice for dropping Type 91 Mod 2 (w/ wooden tail fin extension) torpedoes in shallow water in preparation for the Hawaii operation was done in Kagoshima Bay. That’s at the southern tip of Kyushu, Nagasaki is on the western end basically. I don’t know how that relates to the anecdote but that’s pretty well documented. It’s true the main Japanese aerial torpedo factory before and during the war was Nagasaki Arsenal, which was barely a target prior to the atomic bombing (some B-24, B-25 and A-26 raids from Okinawa bombed industrial targets and shipping at Nagasaki during July 1945, and there was one night B-29 raid against the area from China in August 1944). This is another factor in (lack of) Japanese defensive reaction to the atomic bombings: they were against secondary areas from both Japanese and prior US POV. Japanese fighters intercepted Allied a/c in the Tokyo Bay area in some cases right to the end, even after the end (like B-32’s on recon intercepted by Japanese Navy fighters on Aug 18).