Cover photo: Captain Okuyama and Giretsu Airborne unit depart on their mission to Okinawa, 24 May 1945.

“The long-awaited day has finally arrived. You may not know just how much I’ve been waiting for this day.
Once a flower blooms, it must eventually scatter. I will proudly bloom this flower for you to see.“
— Sergeant Kei Ito, Giretsu Kuteitai Unit.

The Giretsu Kuteitai (literally meaning “heroic paratroopers”) was an airborne special forces unit of the Imperial Japanese Army Air Force. It was formed in November 1944 in a desperate attempt to counter the strategic bombing of Japan’s mainland territories.

From the Teishin Shudan special forces unit (regimental level), the 1st Raiding Regiment was formed under Captain Michiro Okuyama. He, with 126 men (the 4th Company), formed the Giretsu team. Initially organized into five platoons and one independent team, along with 8 agents. The British historian Mark Felton, praised Okuyama, the commander of the Giretsu Airborne Unit, as “an incredibly brave and talented soldier“.

Plans for destroying B-29 bombers included the use of armor-piercing bombs, two-kilogram bombs with handles, and belt explosives. However, it was not easy to install explosives on the upper edge of the large B-29, which was 4.5 meters above the ground. Nevertheless, the highly skilled airborne troops gradually mastered the techniques through rigorous daily training.

In April 1945, during Showa 20 in the Japanese calendar, the Allies launched an invasion of Okinawa, signaling the start of the Battle of Okinawa. By May, multiple aircraft from the USAF and Marine Corps had taken control of several airfields across Okinawa, initially built by the Japanese but later captured by the Americans. This presented a major challenge to Japanese air operations in the Okinawa area, which heavily depended on kamikaze tactics.

The Imperial Headquarters made the decision to focus the remaining Japanese air power on aiding the retreat of the 32nd Army to southern Okinawa and executing special attack missions. This included deploying the Giretsu Airborne Unit to conduct airborne special operations (Operation Gigo) targeting the airfields of Okinawa Island. The Giretsu Airborne Unit was transferred from Nishi-Tsukuba to Kengun, Kumamoto Prefecture, and placed under the authority of the 6th Air Army.

The lack of a withdrawal plan for the force, combined with the rejection of tradition in Japanese military doctrine at that time, meant that Giretsu operations were essentially suicide attacks. Okuyama’s final words before departing for the mission were: “I depart on my final sortie as the commander of the regiment, the long-awaited day of the warriors has finally come. Training and enthusiasm for the encounter with the American enemy herald our ultimate purpose. Today then.”

Operation Gigo, along with the subsequent night bombings, represented the most extensive nighttime assaults on American airfields in Okinawa up to that point. To enhance the impact of the bombings, timed bombs were fitted onto the bombers prior to their missions. Vice Admiral Matome Ugaki, Commander of the Fifth Air Fleet, decided to deploy 17 Type 1 land-based attack aircraft, 13 Ginga bombers, and 12 night fighters as escorts to support Operation Gigo.

On the night of May 24, 1945, 12 Ki-21-IIb aircraft each carrying 12 commandos departed for the Yomitan and Kadena bases. The airborne troops were equipped with various firearms, including the rare Type 100 submachine gun and Type 89 grenade discharger, which were in short supply within the Japanese military.

Additionally, each soldier carried 10-15 hand grenades in bandoliers or sacks, along with demolition equipment such as armor-piercing grenades and two-kilogram bombs with handles. Each transport plane carried 2-3 flight squadron members and 11-12 airborne troops onboard. Following a forced landing, the airborne troops were trained to operate in teams of three, with each team comprising three individuals, a principle emphasized by the unit’s leader, Okuyama, who often reiterated, “Three men, three comrades for life.”

Four aircraft aborted the mission due to engine trouble, and three others were shot down, but five managed to reach Yontan Airfield, with only one landing successfully. The only successful forced landing at Yontan Airfield was executed by Lieutenant Nobufumi Harada, a graduate of the Nakano School Futamata Branch, who led the No. 4 aircraft. Alongside Commander Harada, the No. 4 aircraft accommodated ten members of the Giretsu Airborne Unit. Yet, it was enough.

The approximately 10 surviving raiders, armed with submachine guns and explosives, spread chaos. The members of the Giretsu Airborne Unit moved with precision and speed, executing their actions without any wasted effort. They navigated swiftly between parked aircraft, adhering to their training protocols by placing bombs on larger planes and hurling grenades at smaller ones, methodically dismantling the aircraft one by one. Meanwhile, the American forces stationed at Yontan Airfield were caught off guard.

With few ground troops present during the infiltration, inexperienced fighter pilots, maintenance personnel, and Marine Corps anti-aircraft gunners found themselves thrust into combat against the Giretsu Airborne Unit. While some Marines maintained composure in the face of the unexpected assault, many others succumbed to panic, mistakenly believing that only a handful of Japanese soldiers had infiltrated, resulting in indiscriminate firing of weapons, including anti-aircraft guns, in all directions.

Witnessing the intense battle firsthand, Marine Corps aviation officer Colonel Ronald D. Salomon remarked, “It was truly terrifying… one of the most exhilarating nights I’ve ever seen in all the wars I’ve witnessed,” expressing his fear. An accompanying American war correspondent described the situation at Yontan Airfield as “a hellish confusion,” illustrating the chaotic nature of the combat.

The few Japanese raiders burned 70,000 gallons of fuel, destroyed or heavily damaged 38 aircraft, and killed or wounded 37 American soldiers. Among the American aircraft 3 Vought F4U Corsair fighters, 4 C-47 transports, and 2 PB4Y-2 Privateer bombers were completely destroyed, while significant damage was inflicted on 29 others (2 PB4Y-2 bombers, 3 F6F fighters, 22 F4U fighters, 2 C-47 transports). The airport remained non-operational until 08:00-10:00 the next day.

An hour after the battle began, reinforcements arrived from Marines, clearing surviving paratroopers at Yi Rong, and the confusion at the airfield gradually subsided. By 13:00, all resistance had ceased. A member of the raiding party survived and managed to cross the battlefield, reaching the headquarters of the 32nd Army in Okinawa on June 12th.

Sources:

U.S.Army, “Okinawa: The Last Battle”, publ. University Press of the Pacific, 2005.

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