Smilin' Jack Sunday strip (1956) by Mosley

April 8, 1956. Chicago Tribune-Daily News Syndicate, Inc. (also known as Chicago Tribune-New York News Syndicate and Tribune-New York (Daily) News Syndicate, now called Tribune Content Agency).

Smilin' Jack is a nice addition to the aviation strips. I like the test pilot humor, Jack's G-force contorted face, and the aircraft--F-80 Shooting Star and supersonic test plane--that complement the Korean War fighter jet pages and 1935 Skyroads sub-sonic plane.

The supersonic prototype looks like the Bell X-1 that Chuck Yeager flew to break the sound barrier for the first time in 1947. Yeager also was a test pilot for the F-80, an early military jet that saw service in the Korean War. It took a backseat later in the war to the superior swept-wing Sabre and Russian MiG jets.

Smilin' Jack was the longest running airplane strip, appearing in newspapers for 40 years (1933-1973). Its creator was aviation enthusiast Zack Mosely, who previously worked on Buck Rogers and Skyroads.

The strip and hero started as On the Wing and Mack Martin, respectively. The Chicago Tribune editor didn't like those names so the comic strip became The Adventures of Smilin' Jack and the hero was renamed Jack Martin after the creator's nickname "Smilin' Zack." In later years the strip was simply known as Smilin' Jack. 

Black dots on the original art are register marks to help screen printers line up each color layer accurately on the press, preventing misalignment and color shifts. You occasionally see them on strips.

(Sources: GCD, "What is a Registration Mark and How to Set It Up?" by Erik Draven, March 20, 2025 (https://support.solutionsforscreenprinters.com), Wikipedia)