The remains of a U.S. Army Air Force pilot who disappeared during a World War II reconnaissance mission have been identified more than 80 years after his aircraft vanished over Southeast Asia, ending a decadeslong effort by military investigators and independent researchers to determine his fate.

The Defense POW/MIA Accounting Agency (DPAA) announced July 1 that 1st Lt. Franklin H. McKinney, 21, was officially accounted for on May 15 after forensic analysis confirmed his identity.

McKinney disappeared on Nov. 5, 1944, while flying an F-5E-2-LO Lightning aircraft on a photo reconnaissance mission from Yunnanyi, China, to targets in Thailand and Burma as a member of the 35th Photo Reconnaissance Squadron, 14th Air Force.

McKinney failed to return from the mission, and personnel with the American Graves Registration Service searched along his planned flight path toward the Chinese-Thai border but found no evidence of a crash. His remains were never recovered after the war, and he was declared dead in March 1946.

The breakthrough came after a renewed investigation that began in 2010, when then-U.S. Air Force Academy cadet Daniel Jackson researched McKinney's case. Jackson partnered with Royal Thai Air Force Museum official Sakpinit Promthep and American researcher Richard Hakanson, whose fieldwork helped uncover new evidence pointing to a possible crash site in Thailand.

Researchers located a wartime report from the Royal Thai Air Force Museum describing an aircraft that reportedly had been struck by lightning before crashing in what is now Thailand's Lampang Province. They also identified a witness who helped narrow the search area.

In 2017, 94-year-old Fong Inma told researchers she had witnessed the aircraft crash into what had since become a rice field near Mae Kua village. Her account helped persuade U.S. officials to investigate the site.

DPAA investigators surveyed the site in 2019 and again in 2021 before launching a full excavation in 2022. Recovery teams uncovered aircraft wreckage and possible human remains, which were transported to a DPAA laboratory for examination using modern forensic techniques. Those analyses ultimately confirmed the remains belonged to McKinney.

McKinney was honored during a repatriation ceremony at the U.S. Embassy in Thailand before his return to the United States. He will be buried with full military honors, and a bronze rosette will be placed beside his name on the Tablets of the Missing at the Manila American Cemetery, signifying that he has been accounted for.

"After almost 82 years, Frank McKinney is home again. America has kept its promise," Jackson wrote in his book chronicling the 16-year search.

The 35th Photo Reconnaissance Squadron, known as the "Redhawks," conducted dangerous unarmed intelligence missions deep over Japanese-held territory, gathering aerial photographs that helped Allied commanders track troop movements and plan military operations in China, Burma, and Thailand.

Military historians have credited the squadron's reconnaissance work with providing intelligence that contributed to the Allied campaign in China.

The DPAA continues efforts around the world to recover and identify missing U.S. service members using archival research, archaeological excavations, DNA testing and other forensic methods. According to the agency, more than 81,000 Americans from World War II remain unaccounted for.