Meteorological spy mission

When Peter Schrewe, commander of the freshly minted German U-

boat 537, ordered his vessel’s lines cast off at Kiel in the early morning hours of Sept. 18, 1943, both he and his youthful crew were still in the dark concerning their first mission.

The crew had arrived back at their boat after shore leave to find strange metal canisters stowed where there should have been torpedoes for use in attacking Allied shipping. And there were two mysterious passengers aboard, too, an almost unheard of occurrence on a U-boat on wartime patrol. The senior passenger didn’t look much like a spy; he had the air of a genial university professor. The strangers were scientist Dr. Kurt Sommermeyer and his technical assistant.

After reaching the open Atlantic, Schrewe opened his sealed his orders, read them and announced U-537’s mission to his crew: to avoid contact with the enemy and erect an automated weather-recording and -transmitting station on North American soil, in northern Labrador.

Knowing what the weather was doing in the waters around Newfoundland was an essential bit of intelligence for any prudent northern navigator, but the Germans wanted accurate weather data that would help them more effectively direct their U-boat operations by predicting the timing and routes that outbound Halifax convoys would follow. The automated station carried by U-537 was designed by the Siemens Company and designated Wetterfunkgerandauml;t-Land #26, or WFL #26 (Automated Land Weather Station #26), code-named Kurt.

U-537’s journey toward Labrador was fraught with dangers from Allied air and sea forces and also by the turbulent Atlantic itself. At one point, the sub was forced to surface in hurricane conditions to recharge her batteries, an action that resulted in her large anti-aircraft gun being ripped from her hull by mountainous seas.

The submarine entered Martin Bay, Labrador, on Oct. 22, and under Sommermeyer’s direction, the canisters and masts making up WFL #26 were carefully manhandled to the deck. Each of the canisters weighed approximately 220 lbs, making for awkward transportation to shore in rubber dinghies across the choppy water of the bay. Once ashore, the station components had to be muscled up to a small plateau 170 feet above the water. There, Sommermeyer directed the assembly of the weather station. One of the canisters was labeled with the words Canadian Weather Services (no such organization then existed) to satisfy the curiosity of anyone who might happen upon the installation.

WFL #26 consisted of measurement modules for wind speed, direction, temperature and barometric pressure, as well as advanced and massive long-life nickel-cadmium batteries to power a 150-watt radio transmitter for broadcasting collected data to German forces. The system was ingeniously designed so that the heavy batteries acted as anchors for the radio and instrument masts during high winds. A cylinder with conducting pins in one module formed Morse-code letters when it rotated, to identify the station to German receivers and to identify each measurement character. The Lorenz radio transmitter was set to broadcast on a frequency of 3.94 MHz at intervals during the day. To save power, the design required the transmitter to be on for only three minutes during each broadcast.

Finally, after successfully testing the operation of the automatic station, and after 30 tense hours of having his vessel exposed on the surface in enemy waters, Schrewe ordered U-537 underway on a course for the south coast of Newfoundland.

U-537 met her end a year later on Nov. 9, 1944, while on Far East patrol. She was attacked and sunk with all hands by the submarine USS Flounder, almost halfway around the world from where she had delivered the Third Reich’s only automated North American weather station. Dr. Sommermeyer and one of the crew survived the war. The crewmember, Werner Bendler, left U-537 when it returned to base. By a stroke of good luck, he was sent for officer training and so missed U-537’s doomed voyage to the Pacific.

WFL #26 remained a well-kept secret until found by crew of a Canadian Coast Guard ship in the summer of 1980. It now resides in the Canadian War Museum in Ottawa.

J. Gregory Dill

By Ocean Navigator