Documentary Around the World by Zeppelin is a film by Dutch director Ditteke Mensink made first aired on BBC Four in 2010.

This was one of the most interesting and quality films I've watched lately. The story is about Graf Zeppelin flight around the world in 1929. The route is following  New York - Friedrichshafen - Moscow (didn't stop here) - Tokyo - Los Angeles - New York.

The story is told through the letters and diaries of Lady Grace Drummond-Hay

In 1929, for the first time in history, a Graf Zeppelin circumnavigated the globe. Beneath the enormous airship hung a gondola to accommodate the lucky passengers and crew for the duration of the 21-day voyage, among them the young journalist Lady Grace Drummond-Hay, reporting for the Hearst media empire. Based upon her letters and diaries and told exclusively through archival and newsreel film from the time, this film relives the incredible voyage.

As a crew of forty kept the zeppelin in the air, Lady Grace feasted her eyes on the world's major cities, white alpine peaks, oceans, and swamps, and fell in love with a married man. The rare archival footage gives glimpses of day-to-day life in a zeppelin gondola, Grace listening to one of her fellow passengers playing the accordion, the repair of a tear in the cloth shell during the flight, the sleeping cabins and lounge, and the splendid views from the windows. The film offers a fascinating look into the world of the roaring twenties which would soon be gone forever.

For me, it was interesting to learn more about the crew, as Lady Grace mentions some Soviet professor Karklin. As Karklin sounds Latvian to me, I  decided to learn more. Unfortunately, there is little information about this Soviet guy, just a brief mention that he was a representative of the Soviet government. As in the film, Karklin is referenced just as a professor, we don't have a clue what is his full name. By doing a quick Google search I did find some information, and probably, just probably the Karklin from the film is Karklin Jan Janovich (Карклин Ян Янович (Иван Иванович)) born in 1895 Courland governate (modern-day Latvia)

From the article Карклин Ян Янович + 02.10.1938 we can learn that Karklins was repressed and sentenced to death by Stalin's order in 1938 (The Great Purge), but following paragraphs from Karklins biography leads me to think that he could be the Soviet professor on Graff Zeppelin in 1929 (Rough Google Translate)

In 1924 he graduated from the VAK at the Military Academy of the Red Army. In October of that year he was sent to study at the Higher School of Pilots and Pilot-Observers, which he graduated in 1925, having been appointed to the post of chief of staff of the 6th separate reconnaissance squadron. Since December 1925 - Chief of Staff of the 8th separate reconnaissance air squadron. Then (until October 1927) he worked as the chief of staff of the 30th Air Squadron. From October 1927 he was the commander of the 40th air squadron. Member of the fighting on the Chinese - Eastern Railway  in 1929

Now, from the following Passengers and Crew of Graf Zeppelin’s Round the World Flight of 1929 records, we can learn that professor Karklin actually left the ship in Tokyo in August 1929. Anyhow, more investigation is needed this time.

About Lady Grace

Grace Marguerite, Lady Hay Drummond-Hay (née Lethbridge, 12 September 1895 – 12 February 1946) was a British journalist, who was the first woman to travel around the world by air (in a zeppelin). Although she was not an aviator herself at first, she contributed to the glamour of aviation and general knowledge of it, by writing articles about her aerial adventures for US newspapers in the late 1920s and early 1930s.