Long distance flights by Wäinö Bremer, updated 12.05.2025 - Helicopters, pocket watches, flight simulation, tools.

             

Bremer’s return flight from Cape Town to Helsinki began on April 26, 1932, and concluded with the landing on May 21, 1932.

Based on the book "Sportplan över fyra världsdelar"  the performance envelope of Wäinö Bremer's Junkers Junior, registration OH-ABB, can be discussed across several key areas:

Speed: The Junkers Junior, powered by an 80-horsepower Armstrong Siddeley Genet engine, typically operated with an average speed of between 120 and 130 kilometres per hour. Under favourable wind conditions, this speed could increase significantly, reaching up to 175 kilometres per hour. However, the aircraft's relatively low power meant its speed was heavily impacted by weather. In strong headwinds, the speed could drop significantly, for example, down to 100, 90, or even 80 km/h when fighting a storm. Against a violent storm at low altitude, the speed could be as low as about 40 km/h. Such headwinds could turn a four-hour flight into eight hours or substantially reduce effective ground speed. Conversely, flying with a tropical storm (moving at 130 km/h), Bremer estimated his speed at 180 km/h, indicating the benefit of a tailwind.

Altitude: The aircraft was capable of reaching considerable altitudes. It flew at 1,000 meters over the Gulf of Finland and the Korean mountains. Bremer flew above clouds at 2,000 meters and over mountains at 2,000 meters. He reached 3,300 meters over the Alps and 3,700 meters over the Taurus mountains in Asia Minor. Over Persia and India, he often flew around 3,000 meters, particularly before sunrise to avoid engine overheating in the heat. However, climbing could be slow, sometimes only a few dozen meters per minute, especially in thin air at higher altitudes or when encountering downdrafts. An English pilot reportedly stated that 3,500 meters was needed to avoid strong downdrafts near mountain ranges north of Cape Town. Over China, Bremer sometimes flew very low, around twenty meters, to better observe the land, despite the risk. He also needed 2,500 meters to clear the mountains in New Mexico.

Range/Endurance: To achieve long range, the front passenger seat was replaced by a reserve fuel tank. A capacity of 215 litres was estimated to be sufficient for about twelve hours of flying, although 100 litres was also mentioned as lasting about five hours. These capacities enabled long flight stages, such as a 1,200-kilometer leg from Livingstone to Johannesburg or a 1,500-kilometer leg from El Paso to Kansas City, which took eleven hours. Bremer planned a non-stop flight of 1,400 kilometers from Keijo to Tokyo, indicating the aircraft's potential endurance with sufficient fuel. The actual range was heavily influenced by wind conditions, with headwinds significantly increasing fuel consumption and reducing effective range. Fuel considerations sometimes necessitated adopting a "less lofty plan," such as flying a shorter leg from Bushire to Djask instead of the intended 1,500-kilometer flight to Karachi. Landing with the "last drops of fuel" occurred on several occasions. Saving fuel by slightly reducing engine revolutions at altitude was also a consideration. A sufficient fuel load was critical for takeoff, sometimes limiting the initial amount taken depending on airfield conditions. An inflated seat cushion was carried as a potential life raft for a 300-kilometer flight over the Yellow Sea, highlighting the consideration of endurance over water.

Weather Capability: The Junkers Junior's reliability was tested in all kinds of weather. It frequently flew in strong headwinds, encountered sandstorms, heavy rain, fog, and thunderstorms. Turbulence and gusts were common, tossing the aircraft around. Flying often required navigating by compass above cloud layers when Mother Earth disappeared from view, or flying low beneath clouds when visibility was limited. Hazards included strong downdrafts near mountains and the engine overheating in high temperatures, especially during climbs in hot climates. Bremer described flying through a storm "between the fog bank and the sea" with wheels near the water, and flying in visibility so poor it was "like flying inside a bag" or a "black sack". The aircraft also faced typhoon conditions, described as increasing wind to a storm and then a typhoon, involving howling and roaring. Flying before dawn was necessary in hot climates to take advantage of cooler air and make the aircraft lighter before the sun's "destructive work".

Terrain Capability: The aircraft was equipped with wheels and had mounting possibilities for skis and pontoons, allowing operations from diverse surfaces. Bremer landed on ice, an ice floe, meadows, plains, and grassy airfields. He also landed on a quite stony surface. Landing on unprepared fields presented challenges, such as tall grass, stones hidden by grass, mud, or simply uneven, bumpy ground. Heavily cultivated areas with canals made emergency landings impossible. Landing on short or obstructed fields, like the Adrianople shooting range or the small airfield at Hong Kong, required precise piloting. The aircraft also landed on a flooded airfield in Hanoi. The Junkers' solid construction and sturdy landing gear proved resilient, holding up well even after a hard landing on a bumpy field. At some airfields, the aircraft had to be tethered to cement blocks due to lack of hangars and risk of storms, or pulled/pushed by hand due to ground conditions or limited space. Concrete runways were appreciated for takeoff with a heavy load, but the aircraft typically operated from grass.

In summary, the Junkers Junior OH-ABB was a sturdy and adaptable sport plane for its time, capable of covering vast distances and operating from a variety of surfaces in challenging weather conditions. However, its 80-horsepower engine limited its speed and climb rate, making it particularly susceptible to strong headwinds and requiring careful planning and piloting when flying at high altitudes or near treacherous terrain. Its operational limits were frequently tested by the demanding nature of Bremer's long-distance flights, particularly in regions with extreme heat, powerful storms, and undeveloped infrastructure.

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