The Dogfight where a USAAF B-17 Flying Fortress bomber shot down a Japanese Kawanishi H6K 'Mavis' flying boat

Imperial Japanese Navy H6K Mavis pilot tells the story of when his Flying Boat was Attacked and nearly Shot Down by B-17 Bombers

By Dario Leone
Apr 24 2022
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‘The only chance we had was the relatively small turning radius of our slow plane compared to that of the fast B-17,’ Lt. Hitsuji, H6K ‘Mavis’ flying boat pilot.

The Flying Fortress is one of the most famous airplanes ever built. The B-17 prototype first flew on Jul. 28, 1935.

The first B-17s saw combat in 1941, when the British Royal Air Force took delivery of several B-17s for high-altitude missions. As World War II intensified, the bombers needed additional armament and armor.

The B-17E, the first mass-produced model of the Flying Fortress, carried nine machine guns and a 4,000-pound bomb load. It was several tons heavier than the prototypes and bristled with armament. It was the first Boeing airplane with the distinctive — and enormous — tail for improved control and stability during high-altitude bombing. Each version was more heavily armed.

As we have already explained, in the Pacific, the planes earned a deadly reputation with the Japanese, who dubbed them “four-engine fighters, a claim confirmed by Imperial Japanese Navy (IJN) Lt. Hitsuji, Kōkūtai (851 Air Group), who was commanding a Kawanishi H6K ‘Mavis’ flying boat in November 1942 when he was attacked by a B-17.

The following is a translation from his memoir “Saigo no Hikotei (The Last Flying boat)” (Asahi Sonorama, ISBN4-257-17286-X) and available on

‘”Enemy plane! Close! Starboard and to the rear!” the tail gunner reported.

‘”All men on air to air battle station!” I yelled as I put the plane in a full speed dive to sealevel.

‘It was 0700 November 21, 1942, 150 nautical miles south of Guadalcanal. We were in midst of a very bloody battle, losing flying boats almost every day to unidentified enemy activities. Our boats would have just enough time to radio a consecutive “hi” signal (consecutive signaling of the Japanese Morse code signal for the character “hi”, the initial for “hikoki” or airplane) before the shoot-out followed by silence. Very few survived air combat. If a boat is able to make detailed reports about the enemy, that boat was sure to make it back.

‘Our commanding officer was in distress about the mounting losses, and just a few days ago, I had assured him that this will not go on for long. So far 16 of our boats were lost. I was not about to be number 17. It wasn’t a patrol plane’s duty to engage in air battles, but now I had no choice.

Imperial Japanese Navy H6K Mavis pilot tells the story of when his Flying Boat was Attacked and nearly Shot Down by B-17 Bombers
Kawanishi H6K in flight.

‘I figured that the fight must be decided quickly. The B-17 positioned itself above and to the starboard rear of our plane and followed us with ease. It must be radioing it’s base about our position. One of them was bad enough. If there were two or even fighter planes we did not have a chance. I made a tight turn to the port and headed towards the enemy. The only chance we had was the relatively small turning radius of our slow plane compared to that of the fast B-17.

‘The enemy was obviously surprised at our sudden turn. As we passed each other, our tail cannon fire hit the B-17 and its port inside engine started smoking. The enemy fled, trailing a long streamer of black smoke. The enemy was surprisingly impersistent. We continued our search mission, but I had a feeling that it wasn’t over yet.

‘”Eat your breakfast now before they come back” I ordered and went to the commander’s seat to open my lunchbox. Pretty soon the co-pilot silently pointed his finger forward and to the port. I took a hard look, and there he was. Another big-tailed B-17 heading straight toward us. The one we damaged must have called for help. We were all ready to fight, and I stood up from my seat. I sealed the tank chamber and pulled the fire extinguisher lever. This fills the tank chamber with CO2. All gunners manned their stations. I could see the front gunner grinning in his turret.

‘”Okay we’re ready” someone said.

‘At altitude 30 meters and speed 150 knots, we headed towards squally skied in the direction of our base. The enemy didn’t start his attack immediately. It flew alongside us and passed us. I figured that he was avoiding our tail cannon. It would probably be making a frontal attack. The shoot-out was about to begin.

‘”Here it comes!” someone shouted, and at the same time, the enemy’s front guns and all four of our starboard machine-guns started firing. As we passed each other, I could see the enemy’s tail gun fire, but tracers were way behind us. No hits on either side. We didn’t change our course and headed toward the squall.

‘The faster enemy caught up quickly and crisscrossed our path, attacking as it passed us.

‘We were at very low altitude, and the sea behind us whitened with machine-gun fire. As the shooting went on, this started moving closer and closer. I could not hear anything other than the roar of the machine-guns and the engine noise. I couldn’t keep my eyes off the enemy for a moment. The enemy made its fourth pass, and as it crossed our path, a 50-caliber shell jumped into the cockpit.

‘I heard someone yell “Damn!” and smelled smoke at the same time. I turned around and two men were down on the floor. Our main radio man PO2 Watanabe’s left arm was hanging limp from his shoulder, and blood was shooting up to the ceiling. Flight engineer Leading Mechanic Nakano was down on the floor, holding his left arm, and shouting “Gasoline, gasoline!”

‘He was yelling to the radioman because the spark from the telegram key could set the vaporized gasoline on fire. But the injured radio man continued to send the message that we were combating an enemy bomber. The enemy started making yet another pass.

‘I took off my muffler and threw it to Lt. (jg) Ide who was shooting away, and yelled “Stop his bleeding!” I could see from the tank chamber window that gas was gushing out of a hit tank. It was a miracle that it wasn’t on fire. The floor was soon covered with gas. I injected additional CO2 gas, and I could see the white gas filling the tank chamber. The injured mechanic was still yelling “Gasoline!”. I could only yell back “It’s okay! You worry about yourself!”

‘We were able to stop the radioman’s bleeding, but the enemy still kept attacking. Amid the exchange of machine gun roar, I could hear bullets tearing into our plane. The plane shook under the impact. All four engines were driving at full power.

‘On their sixth pass, the moment I saw their tailgun fire, there was an enormous banging noise up front gunner PO1 Takahashi pointed to the floor beneath the pilot’s seat and I noted a big hole about 30cm, on the keel of our bow. I could see waves from the hole.

‘By this time, I was sure that this enemy has shot down more than one flying boat. “It wasn’t fighters. It was this guy. Another patrol plane! I’m going to get him. He is not going to have any more kill marks!” As I came to this realization, there was a new determination in my mind. If we can’t down him with our guns, we will ram him. I drew and loaded my pistol.

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‘”If worse comes to worst we’ll ram him, okay?” I patted the main pilot Ensign Kobayashi’s shoulder with my pistol. He nodded lightly. “Okay, we’re ready then”. My mind was set. I was going to shoot myself at the moment of the ramming so I would die before the crew.

‘I noted that the side panel of the commander’s seat was burning hot. I was shocked to find the bullet that hit the crew crewmen perched in the panel. Had I not been standing, this bullet would have hit my back! (This bullet is still in my possession).

‘I noticed that the enemy’s fire was getting considerably weaker. Either some of their gunners were knocked out, or they were out of ammo. I was getting the feeling that we may be able to make it when the co-pilot suddenly put the plane in a dive. The sea was right in front of us.

‘”Not yet!” I yelled, thinking that he was about to ram the B-17, but soon realized that our co-pilot PO1 Kira evaded a collision with the enemy who came in from the side. The enemy passed about 30meters behind us. The tail gunner poured an entire drum of 20mm cannon shells into the B-17.

‘The shells all hit the enemy’s fuselage. The enemy passed us from the right, then banked left and started closing into our plane. I could see the enemy pilot’s face. I couldn’t help but fire my pistol at the enemy.

‘Maybe the enemy was trying to ram us too. I noticed all his guns were pointing random directions. He must have been out of ammo. He flew alongside us banking and yawing for a while, but eventually disappeared into the rain towards Guadalcanal, trailing gasoline. “We won!” we said to each other, but we could no longer fight.’

According to, Lt. Hitsuji’s H6K made it back to Shortland, but taxing was something of a small adventure. After splashdown, as soon as the bow came down, water started gushing in from the hole in the bow. Since they did not have material to close the big hole in the bow, they stuffed their life jackets into the hole. This obviously wasn’t holding up, and six men piled up on the life jacket-stuffed hole to stop the water. By the time they were beached, these men had their head barely above water. Everyone was covered with water, oil, and blood.

Their plane #36 (could have been O-36 or 851-36 or 51-36) had endured ninety-three 50 caliber bullets.

Photo credit: Jack Fellows illustration via Weapons and Warfare

Imperial Japanese Navy H6K Mavis pilot tells the story of when his Flying Boat was Attacked and nearly Shot Down by B-17 Bombers
An H6K with a burning wing.

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Dario Leone

Dario Leone

Dario Leone is an aviation, defense and military writer. He is the Founder and Editor of “The Aviation Geek Club” one of the world’s most read military aviation blogs. His writing has appeared in The National Interest and other news media. He has reported from Europe and flown Super Puma and Cougar helicopters with the Swiss Air Force.
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