Jiro has dark brown hair, brown eyes, and he wears a white suit with a blue tie and white pants. He also wears black glasses and white hat.
He also has a happy and good natured personality toward Naoko and loves her very much. Jiro is also trustworthy and hardworking when it comes to his love for airplanes.
At the beginning of the film, Jiro starts out as a young boy living in a provincial town in Japan, who dreams of a day when he could design and possibly fly airplanes. However, much to his dismay, his eye-sight deteriorates rapidly, preventing Jiro from ever piloting an aircraft. His hopeless longing even leads to dreams where he would fall from an airplane he was piloting, as his eyes could not withstand the pressure of high altitudes. Desperate to find a way to overcome his weakness and follow his goal, he seeks help and guidance from Giovanni Caproni, a famous Italian aircraft designer who appears to Jiro in his dreams. Caproni encourages Jiro to become an aeronautical engineer, as he could then follow his desire to design airplanes without actually having to fly one.
Determined to become an aeronautical engineer one day, Jiro studies the principles of aviation throughout his academic years, continuously seeking guidance and encouragement from Caproni along the way. By the time he is an adult, he is able to enter the University of Tokyo to study aeronautics. Boarding a train, he makes his way to the Kanto region of Japan. During the journey, he meets Naoko, a young girl traveling with her maid, for the first time. An unprecedented, deadly earthquake suddenly hits the Kanto region, leaving the city in devastation and fire. The passengers inside the train flee from the train, as the damaged boiler threatens to explode. As Jiro starts to leave, he notices that Naoko's maid had broken her leg during the commotion caused by the earthquake. Strapping his slide-ruler to the side of her leg, Jiro leads both Naoko and her maid to safety. Jiro's actions win affection and gratefulness from Naoko and her maid, but they can not express their thankfulness to him, as Jiro leaves without telling them who he is.
Years later, Jiro works as an aircraft manufacturer and designer for a company in Nagoya, Japan. His first assignment to build a fighter with a design team ends in failure, and the company is forced to give up its contract to a rival company. Redirecting its attention to the designing of a heavy bomber, the company sends Jiro to Germany to study the technical advances of the German Junker aircraft designs. Jiro, with difficulty, succeeds in procuring the necessary designs from the grudging Germans and returns to Japan. Some years later, Jiro is reassigned to a fighter project funded by the Imperial Japanese Navy as the design team's chief designer. This project also ends in failure, causing Jiro to fall into a state of severe disappointment. The company, anxious to have their chief designer back in form, sends Jiro away to a summer resort to recover. There, he meets Naoko once again, now grown into a beautiful young woman. The two soon fall in love, sharing a passionate romance. However, when Jiro proposes to Naoko, she refuses, saying that she was inflicted with tuberculosis. She earnestly entreats Jiro to wait for their marriage until she is cured, which Jiro gently accepts.
Jiro returns to the company after his vacation time expires. He is then assigned to another fighter project sponsored by the Navy as the chief aircraft designer. In order to avoid the attention of the Japanese secret police, the company sets Jiro's lodgings at one of his supervisor's residences. With the help of his design ream, Jiro plans the construction of Japan's future naval fighter, regarding it as a revolutionary step in aeronautics.
After some months of going back to his work, Jiro continues to work on the chief design of his first successful aircraft in the home of his manager. Naoko, meanwhile, has been recuperating in an airplane sanatorium, but, cannot bare being apart from Jiro. They quickly get married through an impromptu wedding. However, they lend support to one another as Naoko's health begins to decline. On the day of the test flight, Naoko feels well enough to take a walk, which results in her leaving Jiro and her family and friends behind.
Jiro eventually completes his fighter design, building the Mitsubishi A5M. Before he leaves to spend the next few nights at the site of the test flight, he and Naoko share their last moment together. While he is at the site, Naoko leaves Nagoya, intending to go back to the sanatorium. She knows that she is going to die, and does not wish Jiro to witness the last terrible moments of her life as she succumbs to the disease.
The test flight goes well. Jiro and his superiors watch as a naval pilot flies the new aircraft to astonishing speeds of 240 knots, a groundbreaking record in flight speeds during that time. As Jiro proudly watches his creation touch down onto the ground, he feels a strong gust of wind from the distant mountains. As he stands against the wind, he senses Naoko's death, leaving him in stunned, anxious suspense.
After World War 2 is over, Jiro revisits his dreams as he did several times in his life, to meet Caproni for, possibly, the last time. Jiro expresses his regret and sorrow of the destruction and devastation his "Zero" fighter had caused during the war. Caproni comforts him, saying that "his dream was nonetheless realized" and that airplanes "were beautiful, cursed dreams". Caproni then directs Jiro's attention beyond the grassy hill they were standing on. Jiro, stunned with joy, sees Naoko coming toward him, holding a parasol in her hand. Waving to Jiro, she calls to him, "you must live, darling...you must live!" Jiro, barely able to speak, nods his head. Her last message complete, she rises with the wind sweeping the grassy landscape they are all in, vanishing from sight. Continuing his walk with Caproni, Jiro looks to the sky and the wind, taking his wife's words deeply to heart.