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Hans Gunter Möller (1912-1979).

He was born in the then village of Großensee, east of Hamburg in the Schleswig-Holstein region, situated between the lower Elbe, Stör, Bille, and middle Trave rivers, which is called Stormarn - part of the name or even the given name of many Möller designs.
After his engineering studies at the Hindenburg Polytechnic in Oldenburg (1930 to 1934), Möller went to Focke-Wulf in Bremen, first as a detail designer, then as a project engineer. In the autumn of 1938, Möller decided to become self-employed and founded an aircraft experimental construction company in Hamburg 39, Maria- Louisen-Straße 65, under his name, with one structural engineer and three craftsmen as permanent employees, as well as eight freelancers.
Before establishing his own factory for canopies and other aircraft parts in Zawiercie (Warthenau/Ziegenhals), which had been part of Poland since 1921, Möller had already completed a period of intensive design work.
In 1929 - as a fourth-grader at the Gymnasium in Bad Oldesloh - he built a primitive seat glider, Kumulus, according to his own designs, with which he achieved some admired jumps from a small local hill, attracting considerable attention from the press and the public, before crashing the nine-meter-span structure during a crosswind landing. Also on the granary of his father's estate, a Zögling training glider with a lattice tail was subsequently built according to plans by the RRG (Rhön-Rossitten-Gesellschaft). Its wing had two parallel struts instead of bracing for easier assembly. It was completed in the spring of 1930. In the same year, the braced Zögling, called the Maizepper, was flown, this time with a steel tube forked tail. It had been built in the basement workshop of the Oldenburg Polytechnic. Möller had its performance through rounded wing elements and a boat-like fairing for the pilot, increased.
The highlight of his design work accompanying his studies was to be the 18-meter wingspan, cantilevered, high-performance gull-wing glider Felix. Möller transported the fuselage, manufactured in Oldenburg and loaded with additional components, and measuring almost seven meters in length, to Großensee in a nighttime operation on his motorcycle. On May 18, 1932, christened D-Stormarn by the district administrator in neighboring Trittau, the glider, with the designer at the controls, completed its first successful flight that same day. Due to insufficient flying qualifications, Möller had to hand over his aircraft to an experienced glider pilot, First Lieutenant Hasso Hemmer, at the 1933 Rhön Gliding Competition.
sen, who promptly achieved a flight lasting over four hours. As early as the beginning of 1934, Möller himself stayed aloft for almost two hours with the D-Stormarn during trials for slope soaring in the greater Hamburg area, when he glided along the two-kilometer-long geest ridge between Boberg and Billstedt – a brilliant flying achievement, even if it ended with a landing in a roadside tree. In Lübeck, a second Felix aircraft was built and flown in 1935. Two further developments remained only on paper. For the Rhön competition in 1934, which he entered with the D-Stormarn, and for cross-country gliding flights, such as his target flight from Fulsbüttel via Bad Oldesloh to Großensee, he needed a support crew of at least four people with their own tent accommodations and transport vehicles, which he called "my little circus."
To reduce these expenses, he repeatedly considered installing an auxiliary engine.
His first of these projects, the Stohimo, was probably the most elegant of his designs, and the last with a curved gull wing. For this, the wing structure had a swept leading edge, which, together with the straight trailing edge and the strongly rounded wingtips, would become a characteristic of subsequent Möller designs. In search of a power source for the motor glider, the Oldenburg Zündapp representative provided a 350cc engine that had powered a motorcycle belonging to the then-racing idol Bernd Rosemeyer, specifically for sand track competitions. The engine, capable of producing a maximum of 12 hp (8.8 kW), was intended to catapult the 13-meter wingspan, 260 kg single-seater from any 50 by 30 meter field using hand-stored energy and operate on 4 liters of regular gasoline per flight hour.
But construction never took place, although motor gliders retained a high status even until the new beginning in the fifties, when Möller preferentially designed his aircraft with two tail booms. Pure motor-powered aircraft, which he called Stomo (Stormarn- Motor), consumed all of Möller's free time, since then, during the 1936 Summer Olympics in Berlin had been called to a light aircraft meeting.
The Stomo 1 was a single-seater designed and built with the brand-new, air-cooled, 22 hp (16.2 kW) FL2x 400 two-cylinder two-stroke engine from the Pinneberg-based Ilo Works. It was intended as a high-performance training aircraft to economically prepare young A2 pilots for the performance and flight characteristics of a 60 to 90 hp (44 kW) aircraft.
For the aerodynamically ideally shaped fuselage with an oval cross-section, Möller chose a completely new arrangement for the 10.5-meter wingspan wing, designed with a swept leading edge, namely the inverted gull shape, in order to keep the two wheelsets attached at the lower
kink position short and thus easy to build.
Möller didn't reap any laurels with his sleek and fast Stomo 7 (D-YBIM), especially because, at its presentation at the Olympic Airshow on July 31, 1936, in Tempelhof, a contemporary trade journal attributed the design to lecturer Bock of the Hamburg State Technical Colleges and its affiliated FAG (Aeronautical Working Group) – an error that proved to be true in Post-war literature continued.
With the Stomo 2, the project for another 20-hp single-seater was created, whose 10-meter wingspan with a swept leading edge was more moderately curved at the root, since the sharp kink of the predecessor model had proven aerodynamically disadvantageous.
Möller considered the engine output of approximately 20 hp (14.7 kW) to be perfectly adequate to power a single-seater - after all, economic efficiency was the primary concern. For, he calculated, if such an engine consumed 5.4 liters of fuel mixture per hour, at a fuel price of 40 pfennigs per liter, the flight hour would cost less than 2.20 RM (Reichsmarks; the average hourly wage at the time was 0.75 RM). But, Möller continued, if the aircraft is aerodynamically engineered to a high standard, the production price only increases moderately, however, 150 km of distance can be covered at the same cost.
Following these considerations, Möller – by then in a relationship with the daughter of a prominent restaurateur from Hamburg and, moreover, enjoying the patronage of Hamburg city councilor Gustav Ruth (founder and owner of the Temperol works in Wandsbek, which also produced aircraft paints) – set about realizing his Stomo 3, the construction work for which was completed in the spring of 1937. During its development, no fewer than 12 designs were drawn up, of which three could be implemented.
The reason for the start of construction of the first prototype was the 1st German Motor Glider Competition, announced by the Reich Air Sports Leader of the newly founded National Socialist Flying Corps (NSFK) (April 17, 1934), which was to be held in September 1937. The conditions for participating aircraft (the (had to be approved!) stipulated a maximum engine
power of 20 hp (14.7 kW), a maximum takeoff weight of 275 kg including fuel for a flight of 200 km in calm conditions, and a maximum foldable size of three meters in height and 2.50 meters in width.
Applicants had to register by August 5th.
The Stomo 3 V 1 Temperolus (the model was given this name) in honor of his patron), which – although also built by Möller with a few helpers – usually during leisure time – took shape in just a few months, generally corresponded to the Stomo 1, but had smoother lines and a less pronounced wing kink, at whose lowest points faired single-leg landing gear units were bent. The originally intended inline four-cylinder engine could not be installed due to excessive power output.
Instead, Möller had to resort to the Kröber M4 boxer engine, a development from the Köller two-stroke engine of the early 1930s, which was significantly lighter and required an abnormally long engine mount. A disc was placed on the front of the propeller hub, which allowed the engine to be started with a rope.After the trouble-free building inspection, the aircraft – folded up – was rolled from Fland through Bremen's streets to the airfield. There, on August 29, 1937, the maiden flight took place – on a Sunday.

The "Bremer Nachrichten" wrote about it: "At 12:30, the bird stood fully assembled in the bright sunshine on the airfield. It could take off, but the test pilot was still missing. Then a machine appeared in the sky, a small Klemm, with a competition number. Hurrah! Kuchi Kuchenmeister, our test pilot, came directly from a competition in Italy, got out of his machine and into the Bremen new design, the Stomo 3. Then he took off. The new aircraft looks good in the air." The colorless protective coating, the transparent surfaces, the two engine cylinders, and the rotating propeller unite to form an organic whole. A few minutes after the clean landing, a motor vehicle rolls up. Director Tank, the head of the Focke-Wulf works
(Note: and thus Möller's highest-ranking boss) gets out. He inspects the aircraft, gets in, taxi, takes off, flies a few circuits and lands. Afterwards, he expressed his appreciation for the good flight characteristics of the small aircraft and wished Möller all the best for the motor glider competition in Rangsdorf.
Besides the Möller Stomo 3 V 1 Temperolus with the now Under the granted registration D-YDOL, ten other aircraft had gathered for the comparative flying event, which took place from October 13th to 17th in Rangsdorf. However, according to the regulations, only two could be classified as powered gliders.
The others were either motor gliders or small aircraft, of which the brilliantly flown Möller design proved to be the fastest. During a subsequent demonstration flight, the Stomo 3 1/7 was completely destroyed. Pilot Kuchenmeister was fatally injured.
Six months later, a new Temperolus was completed, the Stomo 3 V3 D-YDAL, which was named Kuchi in honor of the deceased pilot.
It was identical to the V 7 and was also powered by the 18.5 hp (13.6 kW) Kröber M 4 engine, but had a one-piece wing with a slightly smaller wingspan and a rudder without a compensating horn. It was maiden-flown by the Hamburg flight instructor Carl Kuchenmeister, a younger brother of "Kuchi." On September 28, 1938, the Aero Club of Germany registered a record attempt from London's Croydon Airport to Königsberg in East Prussia (now Kaliningrad), which Kuchenmeister was to carry out with the aircraft at the end of October, depending on the weather. But that didn't happen: On October 1, 1938, Hans Gunter Möller, contrary to the interests of the RLM (Reich Air Ministry), which had proposed his cooperation with one of the established but underutilized companies (Siebel in Halle, Gotha Wagon Factory, or Fieseler in Kassel), founded his own company in Hamburg. On the same day, he hired 19-year-old Max Brandenburg (who had obtained his B 2 pilot's license on September 22, 1938) as a test pilot. Brandenburg first flew the D-YDAL on the 12th of the month and criticized, among other things, the one-piece wing, which proved too cumbersome for land transport, the unusually long takeoff distance due to the low engine power, and the overall unreliability of the engine. Nevertheless, the young pilot still managed to log almost 28 hours of flight testing on the Stomo 3 V 3, achieved in 34 flights, four of which ended in emergency landings due to engine failure.
On June 10, 1939, the aircraft was grounded because of the underpowered engine. It was to receive a more powerful Seld engine. A photograph shows it, engineless, next to the Stomo 3 V 7 Sturmer – the version that ultimately brought honor and success to the design (and almost to series production). But that is a story in itself, which will be told in a second part.