"The callsign of the F-22 that shot down the Chinese spy balloon was a nod to Frank Luke Jr., a legendary World War I pilot who destroyed over a dozen German balloons and several aircraft during his brief time in combat as a member of the United States Army Air Service. For his efforts in the skies above the battlefield, Luke became famous as the “Arizona Balloon Buster,” according to the US Air Force.
Frank Luke Jr. (May 19, 1897 – September 29, 1918) was an American fighter ace credited with 18 aerial victories, ranking him second among United States Army Air Service pilots after Captain Eddie Rickenbacker during World War I. Luke was the first airman to receive the Medal of Honor and first USAAS ace in a day.
Between September 12 and 29, Luke was credited with shooting down 14 German balloons and four airplanes:[5] Luke achieved these 18 victories during just 10 sorties in eight days, a feat unsurpassed by any pilot in World War I.[1]
So four aircraft and fourteen balloons. Five shootdowns to be an ace, so they must count balloons.
They had observation balloons in World War I. Could see if those counted.
googles
It looks like it.
https://www.businessinsider.com/meet-ace-wwi-pilot-famous-for-shooting-down-enemy-balloons-2023-2?op=1
"The callsign of the F-22 that shot down the Chinese spy balloon was a nod to Frank Luke Jr., a legendary World War I pilot who destroyed over a dozen German balloons and several aircraft during his brief time in combat as a member of the United States Army Air Service. For his efforts in the skies above the battlefield, Luke became famous as the “Arizona Balloon Buster,” according to the US Air Force.
https://en.wikipedia.org/wiki/Frank_Luke
So four aircraft and fourteen balloons. Five shootdowns to be an ace, so they must count balloons.