Yokosuka MXY7 Ohka The was a purpose - built , rocket powered human - guided anti - shipping " kamikaze " attack plane employed by Japan towards the end of World War II . United States sailors gave the aircraft the nickname Baka ( Japanese for " fool " or " idiot " ) . Design and development . The MXY - 7 Navy Suicide Attacker Ohka was a manned flying bomb that was usually carried underneath a Mitsubishi G4M 2e " Betty " Model 24J bomber to within range of its target ; on release , the pilot would first glide towards the target and when close enough he would fire the " Ohka " s three solid - fuel rockets , one at a time or in unison , and fly the missile towards the ship that he intended to destroy . The design was conceived by Ensign Mitsuo Ohta of the 405th Kokutai , aided by students of the Aeronautical Research Institute at the University of Tokyo . Ohta submitted his plans to the Yokosuka research facility . The Imperial Japanese Navy decided the idea had merit and Yokosuka engineers of the Yokosuka Naval Air Technical Arsenal ( Dai - Ichi Kaigun Koku Gijitsusho , or in short " Kugisho " ) created formal blueprints for what was to be the MXY7 . The only variant which saw service was the Model 11 , and it was powered by three Type 4 Mark 1 Model 20 rockets . 155 Ohka Model 11s were built at Yokosuka , and another 600 were built at the Kasumigaura Naval Air Arsenal . The final approach was almost unstoppable because the aircraft gained high speed ( in level flight and or even in a dive ) . Later versions were designed to be launched from coastal air bases and caves , and even from submarine s equipped with aircraft catapult s , although none were actually used in this way . It appears that the operational record of " Ohkas " includes three ships sunk or damaged beyond repair and three other ships with significant damage . Seven US ships were damaged or sunk by " Ohkas " throughout the war . The USS " Mannert L . Abele " was the first Allied ship to be sunk by Ohka aircraft , near Okinawa on 12 April 1945 . The " Ohka " pilots , members of the " Jinrai Butai " ( Thunder Gods Corps ) , are honored in Japan at " Ohka " Park in Kashima City , the " Ohka " Monument in Kanoya City , the Kamakura " Ohka " Monument at Kenchō - ji Kamakura , and the Yasukuni Shrine in Tokyo . The only operational " Ohka " was the Model 11 . Essentially a 1 , 200 kg ( 2 , 646 lb ) bomb with wooden wings , powered by three Type 4 Model 1 Mark 20 solid - fuel rocket motors , the Model 11 achieved great speed , but with limited range . This was problematic , as it required the slow , heavily laden mother aircraft to approach within of the target , making them very vulnerable to defending fighter s . There was one experimental variant of the Model 11 , the Model 21 , which had thin steel wings manufactured by Nakajima . It had the engine of the Model 11 and the airframe of the Model 22 . The Ohka K - 1 was an unpowered trainer version with water ballast instead of warhead and engines , to provide pilots with handling experience . 45 were built by Dai - Ichi Kaigun Koku Gijitsusho . The Model 22 was designed to overcome the short standoff distance problem by using a Campini - type thermojet engine , the Tsu - 11 . This engine was successfully tested , and 50 Model 22 " Ohkas " were built at Yokosuka to accept this engine . The Model 22 was to be launched by the more agile Yokosuka P1Y3 " Ginga " " Frances " bomber , necessitating a shorter wing span and much smaller 600 kg ( 1 , 320 lb ) warhead . None appear to have been used operationally , and only three of the experimental Tsu - 11s engines are known to have been produced . The Model 33 was a larger version of the Model 22 powered by an Ishikawajima Ne - 20 turbojet with a 800 kg ( 1 , 760 lb ) warhead . The mothership was to be the Nakajima G8N " Renzan " . Model 33 was cancelled due to the likelihood that the " Renzan " would not be available . Other unbuilt planned variants were the Model 43A with folding wing s , to be launched from submarines , and the Model 43B , a catapult / rocket assisted version , also with folding wings so that it could be hidden in caves . A trainer version was also under development for this version , the two - seat Model 43 K - 1 Kai Wakazakura ( Young Cherry ) , fitted with a single rocket motor . In place of the warhead , a second seat was installed for the student pilot . Two of this version were built . Finally , the Model 53 would also use the Ne - 20 turbojet , but was to be towed like a glider and released near its target . Operational history . The Yokosuka MXY7 Ohka was used mostly against American ships invading Okinawa , and if launched from its mothership , could be extremely effective due to its high speed in the dive . In the first two attempts to ship the " Ohka " s to Leyte Gulf through aircraft carriers , the carriers and were sunk by the US submarines USS " Archer - Fish " and USS " Redfish " . Attacks intensified in April 1945 . On 1 April 1945 , six " Bettys " attacked the U . S . Fleet off Okinawa . At least one made a successful attack , with its " Ohka " thought to hit one of the 406 mm ( 16 in ) turrets on the battleship , causing moderate damage . Postwar analysis indicated that no hits were recorded and that a near - miss took place . The transports , , and were also hit by " kamikaze " aircraft , but it is unclear whether any of these were " Ohkas " from the other " Bettys " . None of the " Bettys " returned . The American military quickly realized the danger and concentrated on extending their " defensive rings " outward to intercept the " Betty " / Ohka combination aircraft before the suicide mission could be launched . On 12 April 1945 , nine " Bettys " attacked the U . S . Fleet off Okinawa . The destroyer was hit , broke in two , and sank , witnessed by LSMR - 189 CO James M . Stewart . destroyed an " Ohka " with AA fire 45 m ( 50 yd ) from the ship , but the resulting explosion was still powerful enough to cause extensive damage , forcing " Jeffers " to withdraw . The destroyer was attacked by two " Ohkas " . One struck just above the waterline just behind the ship ' s bow , with the charge punching completely through the other side of the hull before splashing into the sea and detonating like a depth charge , causing little damage to the ship , and the other " Ohka " narrowly missed ( likely due to the pilot being killed by anti - aircraft fire ) and crashed into the sea , knocking off the " Stanly " s ensign in the process . One Betty returned . On 14 April 1945 , seven " Bettys " attacked the U . S . Fleet off Okinawa . None returned . None of the " Ohkas " appeared to have been launched . Two days later , six " Bettys " attacked the U . S . Fleet off Okinawa . Two returned , but no " Ohkas " hit their targets . Later , on 28 April 1945 , four " Bettys " attacked the U . S . Fleet off Okinawa at night . One returned . No hits were recorded . May 1945 saw another series of attacks . On 4 May 1945 , seven " Bettys " attacked the U . S . Fleet off Okinawa . One " Ohka " hit the bridge of a minesweeper , , causing extensive damage and casualties . was also damaged by a near - miss by an " Ohka " . One " Betty " returned . On 11 May 1945 , four " Bettys " attacked the U . S . Fleet off Okinawa . The destroyer was hit and suffered extensive damage and flooding . The vessel was judged beyond repair . On 25 May 1945 , 11 " Bettys " attacked the US Fleet off Okinawa . Bad weather forced most of the aircraft to turn back , and none of the others scored hits . On 22 June 1945 , six " Bettys " attacked the U . S . Fleet off Okinawa . Two returned , but no hits were scored . Postwar analysis concluded that the Ohka ' s impact was negligible with no US Navy capital ships actually hit during their attacks due to an extremely effective set of defensive tactics that were employed . Surviving examples . Some 852 were built , mostly Model 11 . Surviving Ohkas include :