John M. Larsen & the JL-6

Background of Larsen and the JL-6

photo: Ernie, Larsen in the middle, unknown pilot

Coming here in 1892 and settling in Omaha, John M. Larsen had made a fortune manufacturing refrigeration equipment in the USA. During World War I he became intensely interested in aviation. In a narrative twist, Larsen first saw the Junkers F13, which he would later promote in the United States, in 1919 when he was in Europe promoting the Curtiss MF Seagull flying boat. Larsen, and a pilot named Carl Truman Batts, took a Curtiss to Norway to demonstrate. In the course of their demonstration, Larsen and Batts became the first to cross the sea between Norway and Denmark by flying boat. It is believed that Larsen himself was at the controls for this flight.

An article in The Edmonton Bulletin, March 24, 1921, explained that Larsen took a Curtiss to Europe

“for the purpose of showing the Danes how to fly. On arrival, he was rather surprised to find that his former compatriots were in no need of education along these lines, and discovered that they had accepted the all-metal model and were building them in Denmark.

Being struck with the good points of the machines, Mr. Larsen went to Germany to the headquarters of the building concern, and obtaining the manufacturing rights for this side of the Atlantic.”

Larsen obtained the rights to assemble and sell the F13 in North America, signing a sales cooperation agreement in 1919. He began a promotional tour within the US in May 1920 and quickly sold eight of the aircraft, designated in this market as the JL-6, to the US Post Office.

The Junkers F13 was a six seated monoplane that was entirely made out of metal. In a era when most aircraft were constructed of wood and fabric, the JL-6 was the world’s first all-metal aircraft, using corrugated Duralumin for the skin. It could accommodate four passengers and two pilots. Also, and significantly for our story, the JL-6 was equipped with the BMW IIIa engine.

Aside from its revolutionary design, the JL-6 was a remarkable aircraft, quickly setting world records for speed, altitude, economy, and endurance. The interior was remarkably comfortable, according to passengers who rode in it. Click here for a list of technical specifications.

Unfortunately, the JL-6 also had a tendency to catch fire in mid-air and by early May 1920 the US Air Mail Service lost a crew due to an engine fire. The US Air Mail Service grounded all of its JL-6 aircraft until the cause of these fires could be discovered. The Smithsonian's National Postal Museum, in Washington, DC, generally dismisses the JL-6 as a tragic mistake.

It turned out that a leak in the fuel line was to blame, the result of a modification Larsen introduced when he brought the Junkers F13 into this market. Hugo Junkers also noted that the JL-6 used a blend of gasoline and benzol rather than straight benzol as fuel, which he proposed might have contributed to the accidents. It is noteworthy that the Junkers F13 performed satisfactorily in Europe.  In fact, the F13 dominated the market in Europe: within five years of its release, the F13 was used on three-quarters of all air routes within Europe.

Some JL-6 aircraft were sold to Imperial Oil Company, of Canada, and a few were sold to various buyers. By 1922, Larsen was unable to sell any more of the Junkers aircraft.

Ernie’s documents includes a copy of a letter from Larsen’s insurance agency, The Home Insurance Company, dated October 24, 1921, in which E. Stockton Martin, Manager of the Aircraft Department, compliments Larsen “on your exceptional record of operation of JL planes.... We appreciate the fact that you have made numerous cross continental trips from New York to San Francisco and return, and others into Mexico and Canada nearing the Arctic Circle, some of which were made under very trying conditions.” Martin states that the company feels “that the right machines, properly flown are a pretty safe risk both for the public and for the insurance companies. An experience such as you have had for the past two years is a tribute not only to yourself but to aviation as a whole.”

There is an excellent book on the F13 and it spends quite a bit of time discussing the JL-6. (Andersson, L.; Endres, G.; Mulder, R.J.M.; Ott, G. 2012. Junkers F13: The World's First All-Metal Airliner. West Sussex: EAM Books EEIG). 

the problem with the JL-6 gas line


Images this page

  • all photos and documents -- EBC
  • Link to transcontinental routes opened with the JL-6
  • Link to airmail route
  • Link to Amundsen's polar expedition