HomeLatest ThreadsGreatest ThreadsForums & GroupsMy SubscriptionsMy Posts
DU Home » Latest Threads » Forums & Groups » Main » General Discussion (Forum) » 77 Years Ago Today; US ca...

Wed Jul 10, 2019, 06:52 AM

77 Years Ago Today; US captures "Akutan Zero", nearly intact A6M Zero fighter - runs flight tests

https://en.wikipedia.org/wiki/Akutan_Zero


The Akutan Zero is inspected by US Navy personnel on Akutan Island on July 11, 1942.

The Akutan Zero, also known as Koga's Zero and the Aleutian Zero, was a type 0 model 21 Mitsubishi A6M Zero Japanese fighter aircraft that crash-landed on Akutan Island, Alaska Territory, during World War II. It was found intact by the Americans in July 1942 and became the first flyable Zero acquired by the United States during the war. It was repaired and flown by American test pilots. As a result of information gained from these tests, American tacticians were able to devise ways to defeat the Zero, which was the Imperial Japanese Navy's primary fighter plane throughout the war.

The Akutan Zero has been described as "a prize almost beyond value to the United States", and "probably one of the greatest prizes of the Pacific War". Japanese historian Masatake Okumiya stated that the acquisition of the Akutan Zero "was no less serious" than the Japanese defeat at the Battle of Midway, and that it "did much to hasten Japan's final defeat". On the other hand, John Lundstrom is among those who challenge "the contention that it took dissection of Koga's Zero to create tactics that beat the fabled airplane".

The Akutan Zero was destroyed in a training accident in 1945. Parts of it are preserved in several museums in the United States.

Mitsubishi A6M Zero fighter
The Second Sino-Japanese War began in 1937. Attacks by Chinese fighter planes on Japanese bombers led the Japanese to develop the concept of fighter escorts. The limited range of the Mitsubishi A5M "Claude" fighter used to escort the bombers caused the Japanese Navy Air staff to commission the Mitsubishi A6M Zero as a long-range land- and carrier-based fighter.

The Zero, which first flew in 1939, was exceedingly agile and lightweight, with maneuverability and range superior to any other fighter in the world at that time. The Zero was superior to any Allied fighter it encountered for the first two years of the war. To achieve this, however, Japanese engineers had traded off durability. The Zero was very lightly built; it had no armor and no self-sealing fuel tanks. According to American author Jim Rearden, "The Zero was probably the easiest fighter of any in World War II to bring down when hit ... The Japanese ... were not prepared to or weren't capable of building more advanced fighters in the numbers needed to cope with increasing numbers and quality of American fighters". The Zero was the primary Japanese Navy fighter throughout the war. During the war, the Japanese manufactured roughly 10,500 Zeros.

In 1940 Claire Lee Chennault, leader of the Flying Tigers, wrote a report on the Zero's performance. However, United States Department of War analysts rejected it as "arrant nonsense" and concluded the performance attributed to the Zero was an aerodynamic impossibility. According to American flying ace William N. Leonard, "In these early encounters and on our own we were learning the folly of dogfighting with the Zero".

Nine Zeros were shot down during the attack on Pearl Harbor. From these wrecks, the Allies learned that the Zero lacked armor and self-sealing fuel tanks, but little else about its capabilities. The Zero's flight performance characteristics—crucial to devising tactics and machinery to combat it—remained a mystery.

Prior to recovery of the Akutan Zero, technical information from three other downed Zeros was available to the Allies. One Zero (serial number 5349), piloted by Hajime Toyoshima, crashed on Melville Island in Australia following the bombing of Darwin. The Zero was heavily damaged, and Toyoshima became Australia's first Japanese prisoner of the Pacific war. Another Zero, piloted by Yoshimitsu Maeda, crashed near Cape Rodney, New Guinea. The team sent to recover the plane erred when they chopped off the wings, severing the wing spars and rendering the hulk unflyable. The third came from China, where Gerhard Neumann was able to reconstruct a working Zero. He used a partly intact Zero (serial number 3372) that had landed in Chinese territory, repaired with salvaged pieces from other downed Zeros. However, bad conditions and the long delivery time from China prevented Neumann's Zero from reaching the United States for testing until after the recovery of the Akutan Zero.

Petty Officer Koga's final mission



Tadayoshi Koga (September 10, 1922 – June 4, 1942) was the pilot of the Akutan Zero.
In June 1942, as part of the Japanese Midway operation, the Japanese attacked the Aleutian islands, off the south coast of Alaska. A Japanese task force led by Admiral Kakuji Kakuta bombed Dutch Harbor on Unalaska Island twice, once on June 3 and again the following day.

Tadayoshi Koga, a 19-year-old flight petty officer first class, was launched from the Japanese aircraft carrier Ryūjō as part of the June 4 raid. Koga was part of a three-plane section; his wingmen were Chief Petty Officer Makoto Endo and Petty Officer Tsuguo Shikada. Koga and his comrades attacked Dutch Harbor, shooting down an American PBY-5A Catalina flying boat piloted by Bud Mitchell and strafing its survivors in the water, killing Mitchell and all six of his crewmen. In the process, Koga's plane (serial number 4593) was damaged by small arms fire.

Tsuguo Shikada, one of Koga's wingmen, published an account in 1984 in which he claimed the damage to Koga's plane occurred while his section was making an attack against two American Catalinas anchored in the bay. This account omits any mention of shooting down Mitchell's PBY. Both American and Japanese records contradict his claims; there were no PBYs in the bay that day. However, his claims do match American records from the attack against Dutch Harbor the previous day (June 3). Rearden noted, "It seems likely that in the near half-century after the event Shikada's memory confused the raids of June 3 and June 4 ... It also seems likely that in his interview, Shikada employed selective memory in not mentioning shooting down Mitchell's PBY and then machine-gunning the crew on the water".

It is not known who fired the shot that brought down Koga's plane, though numerous individuals have claimed credit. Photographic evidence strongly suggests it was hit by ground fire. Members of the 206th Coast Artillery Regiment, which had both 3-inch anti-aircraft guns and .50 caliber machine guns in position defending Dutch Harbor, claimed credit, in addition to claims made by United States Navy ships that were present. Physical inspection of the plane revealed it was hit with small arms fire — .50 caliber bullet holes and smaller, from both above and below.

Crash
The fatal shot severed the return oil line, and Koga's plane immediately began trailing oil. Koga reduced speed to keep the engine from seizing for as long as possible.

The three Zeros flew to Akutan Island, 25 miles east of Dutch Harbor, which had been designated for emergency landings. Waiting near the island was a Japanese submarine assigned to pick up downed pilots. At Akutan, the three Zeros circled a grassy flat half a mile inland from Broad Bight. Shikada thought the ground was firm beneath the grass, but in his second pass he noticed water glistening. He suddenly realized Koga should make a belly landing. But by then Koga had lowered his landing gear and was almost down.

The plane's landing gear mired in the water and mud, causing the plane to flip upside down and skid to a stop. Although the aircraft survived the landing nearly intact, Petty Officer Koga died instantly on impact, probably from a broken neck or a blunt-force blow to his head. Koga's wingmen, circling above, had orders to destroy any Zeros that crash-landed in enemy territory, but as they did not know if Koga was still alive, they could not bring themselves to strafe his plane. They decided to leave without firing on it. The Japanese submarine stationed off Akutan Island to pick up pilots searched for Koga in vain before being driven off by the destroyer USS Williamson.


The Zero trailing oil over Dutch Harbor, moments after being hit.

Recovery


Pilot Bill Thies (left) in front of his Catalina that discovered the Akutan Zero.

The crash site, which was out of sight of standard flight lanes and not visible by ship, remained undetected and undisturbed for over a month. On July 10, 1942, an American PBY Catalina piloted by Lieutenant William "Bill" Thies spotted the wreckage. Thies's Catalina had been patrolling by dead reckoning and had become lost. On spotting the Shumagin Islands, he reoriented his plane and began to return to Dutch Harbor by the most direct course—over Akutan Island. Machinist Mate Albert Knack, who was the plane captain (note: the term "plane captain" in US Navy usage refers to an aircraft's assigned maintenance crew chief, not the pilot-in-command), spotted Koga's wreck. Thies's plane circled the crash site for several minutes, noted its position on the map, and returned to Dutch Harbor to report it. Thies persuaded his commanding officer, Paul Foley, to let him return with a salvage team. The next day (July 11), the team flew out to inspect the wreck. Navy photographer's mate Arthur W. Bauman took pictures as they worked.

Thies's team extracted Koga's body from the plane by having Knack (the smallest crew member) crawl up inside the plane and cut his safety harness with a knife. They searched it for anything with intelligence value, and buried Koga in a shallow grave near the crash site. Thies returned with his team to Dutch Harbor, where he reported the plane as salvageable. The next day (July 12), a salvage team under Lieutenant Robert Kirmse was dispatched to Akutan. This team gave Koga a Christian burial in a nearby knoll and set about recovering the plane, but the lack of heavy equipment (which they had been unable to unload after the delivery ship lost two anchors) meant their efforts failed. On July 15, a third recovery team was dispatched. This time, with proper heavy equipment, the team was able to free the Zero from the mud and hauled it overland to a nearby barge, without further damaging it. The Zero was taken to Dutch Harbor, turned right-side up, and cleaned.


Loading of Akutan Zero on barge.

The Akutan Zero was loaded into the USS St. Mihiel and transported to Seattle, arriving on August 1. From there, it was transported by barge to Naval Air Station North Island near San Diego where repairs were carefully carried out. These repairs "consisted mostly of straightening the vertical stabilizer, rudder, wing tips, flaps, and canopy. The sheared-off landing struts needed more extensive work. The three-blade Sumitomo propeller was dressed and re-used." The Zero's red Hinomaru roundel was repainted with the American blue circle-white star insignia. The whole time, the plane was kept under 24-hour military police guard in order to deter would-be souvenir hunters from damaging the plane. The Zero was fit to fly again on September 20.

Analysis


Eddie Sanders taxiing the plane after its first test flight, September 20, 1942

Data from the captured Zero had been transmitted to the U.S. Navy's Bureau of Aeronautics (BuAer) and Grumman Aircraft. After careful study, Roy Grumman decided that he could match or surpass the Zero in most respects, except in range, without sacrificing pilot armor, self-sealing tanks and fuselage structure. The new F6F Hellcat would compensate for the extra weight with additional power.

On September 20, 1942, two months after the Zero's capture, Lieutenant Commander Eddie R. Sanders took the Akutan Zero up for its first test flight. He made 24 test flights between September 20 and October 15. According to Sanders' report:

These flights covered performance tests such as we do on planes undergoing Navy tests. The very first flight exposed weaknesses of the Zero which our pilots could exploit with proper tactics ... immediately apparent was the fact that the ailerons froze up at speeds above 200 knots so that rolling maneuvers at those speeds were slow and required much force on the control stick. It rolled to the left much easier than to the right. Also, its engine cut out under negative acceleration due to its float-type carburetor. We now had the answer for our pilots who were being outmaneuvered and unable to escape a pursuing Zero: Go into a vertical power dive, using negative acceleration if possible to open the range while the Zero's engine was stopped by the acceleration. At about 200 knots, roll hard right before the Zero pilot could get his sights lined up.


The Zero while temporarily at the Langley Research Center, just after its wind-tunnel tests, March 8th, 1943

In early 1943, the Zero was transferred from Naval Air Station North Island to Anacostia Naval Air Station. The Navy wished to make use of the expertise of the NACA Langley Research Center in flight instrumentation, and it was flown to Langley on March 5, 1943 for the installation of the instrumentation. While there, it underwent aerodynamic tests in the Full-Scale Wind Tunnel under conditions of strict secrecy. This work included wake surveys to determine the drag of aircraft components; tunnel scale measurements of lift, drag, control effectiveness; and sideslip tests.

After its return to the Navy, it was flight tested by Frederick M. Trapnell, the Anacostia Naval Air Station director of flight testing. He flew the Akutan Zero in performance while Sanders simultaneously flew American planes performing identical maneuvers, simulating aerial combat. Following these, USN test pilot Lieutenant Melvin C. "Boogey" Hoffman conducted more dogfighting tests between himself flying the Akutan Zero and recently commissioned USN pilots flying newer Navy aircraft.

Later in 1943, the aircraft was displayed at Washington National Airport as a war prize. In 1944, it was recalled to North Island for use as a training plane for rookie pilots being sent to the Pacific. A model 52 Zero, captured during the liberation of Guam, was later used as well.

Data and conclusions from these tests were published in Informational Intelligence Summary 59, Technical Aviation Intelligence Brief #3, Tactical and Technical Trends #5 (published prior to the first test flight), and Informational Intelligence Summary 85. These results tend to somewhat understate the Zero's capabilities.

</snip>


13 replies, 834 views

Reply to this thread

Back to top Alert abuse

Always highlight: 10 newest replies | Replies posted after I mark a forum
Replies to this discussion thread

Response to Dennis Donovan (Original post)

Wed Jul 10, 2019, 08:32 AM

1. Interesting details. Cadet Bonespurs would have known all those of course.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to Dennis Donovan (Original post)

Wed Jul 10, 2019, 09:19 AM

2. Strafed the PBY survivors in the water.

Son of a bitch in total war.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to Dennis Donovan (Original post)

Wed Jul 10, 2019, 12:09 PM

3. "In these early encounters and on our own we were learning the folly of dogfighting with the Zero".

Joe Foss, Medal of Honor recipient who shot down 26 Japanese planes in WWII, including many during the battle for Guadalcanal while flying the F4F Wildcat, was quoted as saying "If it's one Zero and one Wildcat -- run! You're outnumbered."

Reply to this post

Back to top Alert abuse Link here Permalink


Response to Dennis Donovan (Original post)

Wed Jul 10, 2019, 12:59 PM

4. Interesting! Side topic, and it's just one line in there, but until now

I’d never heard of the raid on Darwin, and I had no idea how often (or at all) that mainland Australia was bombed...

Reply to this post

Back to top Alert abuse Link here Permalink


Response to petronius (Reply #4)

Wed Jul 10, 2019, 02:38 PM

5. Wikipeda article about the bombing of Darwin:

https://en.wikipedia.org/wiki/Bombing_of_Darwin


The explosion of a ship, filled with TNT and ammunition, hit during the first Japanese air raid on Australia's mainland, at Darwin on 19 February 1942. In the foreground is HMAS Deloraine, which escaped damage

The Bombing of Darwin, also known as the Battle of Darwin, on 19 February 1942 was the largest single attack ever mounted by a foreign power on Australia. On that day, 242 Japanese aircraft, in two separate raids, attacked the town, ships in Darwin's harbour and the town's two airfields in an attempt to prevent the Allies from using them as bases to contest the invasion of Timor and Java during World War II.

Darwin was lightly defended relative to the size of the attack, and the Japanese inflicted heavy losses upon Allied forces at little cost to themselves. The urban areas of Darwin also suffered some damage from the raids and there were a number of civilian casualties. More than half of Darwin's civilian population left the area permanently, before or immediately after the attack.

The two Japanese air raids were the first, and largest, of more than 100 air raids against Australia during 1942–43.

</snip>


Not to be confused with "The Bombing of Darwood", which took place on every other episode of Bewitched and was always started by Endora.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to Dennis Donovan (Original post)

Wed Jul 10, 2019, 02:52 PM

6. The folly of bias in war...

In 1940 Claire Lee Chennault, leader of the Flying Tigers, wrote a report on the Zero's performance. However, United States Department of War analysts rejected it as "arrant nonsense" and concluded the performance attributed to the Zero was an aerodynamic impossibility. According to American flying ace William N. Leonard, "In these early encounters and on our own we were learning the folly of dogfighting with the Zero".


Chennault was in China, shooting down Zeroes with obsolete P40s long before the US entered the war. He knew what he was talking about, and devised tactics that took advantage of the P40's superior armor to defeat Zeroes. And no, he didn't "dogfight" with them. The heavier P40s could dive faster and recover from a steeper dive because of its beefier airframe. So basically, his pilots would ambush the Zeroes from above and continue the dive in ways which the Zeroes couldn't keep up. The Flying Tigers had a pretty impressive kill rate considering what they were flying.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to Wounded Bear (Reply #6)

Wed Jul 10, 2019, 02:55 PM

7. The War Department, from the 20's thru the early 40's was a classic example of...

...donkeys leading lions.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to Dennis Donovan (Reply #7)

Wed Jul 10, 2019, 02:58 PM

8. OTOH, they did develop the aircraft carriers...

which ended up being a deciding factor in the war.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to Wounded Bear (Reply #8)

Wed Jul 10, 2019, 04:12 PM

11. This was the same group

that ran Billy Mitchell into the ground despite Mitchell's forward thinking

Reply to this post

Back to top Alert abuse Link here Permalink


Response to Dennis Donovan (Original post)

Wed Jul 10, 2019, 03:04 PM

9. And the World just keeps sliding along.

I love my 1984 Montero.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to snort (Reply #9)

Wed Jul 10, 2019, 03:09 PM

10. I love 70's and 80's Japanese cars...

...somewhere down the road, I want an early 80's Datsun 280ZX.



*drool* (and I've owned a Porsche 928 S4; I still love the 280ZX! )

Reply to this post

Back to top Alert abuse Link here Permalink


Response to Dennis Donovan (Reply #10)

Wed Jul 10, 2019, 04:21 PM

12. Drove a 260z to Vegas to get hitched back in '85.

Fun car but I wish I still had my '67 MGB GT today, though I admit I would re-power it if I did. The right one comes along and I'll buy it.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to Dennis Donovan (Original post)

Wed Jul 10, 2019, 06:09 PM

13. My World War II Army Air grandpa never talked about any of this shit.

He visited Alaska during the war and caught a few fish. He may have caught a few fish in Europe too.

After the war he was an aerospace engineer who worked on the Apollo Project. He was always happy to talk about that.

The world was a huge place then.

A Japanese Zero was an alien artifact.

Reply to this post

Back to top Alert abuse Link here Permalink

Reply to this thread