Vágvölgyi Ádám: Junkers F-13. A Junkers repülőgépek története 1909-től 1932-ig (Budapest, 1990)

Summary (Összefoglaló angolul)

Summary The research work done by Hugo Junkers resulted the first wholly metal built aeroplane with self-supported wings and without outside drag-wires on the world. Junkers established contact with the Aachen Technical Highschool in 1908, when with Prof. H. Reissner they built a fully metal duckarrayed aeroplane. The "Wellblech Ente" was built with thin profiled wings and outside dragwires. In 1909 Junkers applied for patent about a new aeroplane with thick-profiled wings, which had no outside drag-wires and the engine, fueltank, payload and the crew were on the aerofoil. In 1914 the supreme command of Germany charged Junkers with a commission to build an aeroplane from metal. The called "Blechesel" J-l type aeroplane was tested by first-lieutenant Mallinkrodt with success. The J-l was the first aeroplane on the world which was fully metalbuilt, with selfsupported wings. Iron was used to the construction works. Junkers got an order from the army to build six J-2 type aeroplanes which type was the modified version of the J-l. These aeroplanes called "Flying tins" were constructed on a similar way to the J-l, with self-supported, iron sheet wings. Due to the heavy all-up weight — though the J-l aeroplane flew fast enough — but they climbed slowly. After that Junkers gave up the idea of the bearing wing cover system and changed basicly the concept of the whole wing construction. The bearing-force caused by the lifting power was lade to the dural made tubular system inside the wings. This was the basic concept of the J-3 type too but it was partly built only. Later among the Junkers types the J-4 had 5 mm steel-plate cover on the engines and around the seat of the pilot and the navigator. The desing of the J-5 monoplane was ready made but never built. The J-6 was also partly built only. The J-7 was the first self-supported low-winged aeroplane made from light metal. The result of the improvement made on J-7 was the J-9 single seater aeroplane. The futher development from the mentioned type was a two-seater J-8 type which was put into mass production as J-10 type. After the first World War the air transport in Germany started with military aeroplanes. For passenger transport Junkers modified a J-10 type aeroplane. The pasenger seat was covered. The modified aeroplane was put into service between Dessau and Weimar. The modified military aeroplanes did not satisfy the requirements of the civil air traffic. Therefore Junkers instructed his designing office to carry out plans of pas-