Use Essers

Ilse Essers, 1941

Ilse Essers , born as Ilse Kober (born September 24, 1898 in Munich , † February 18, 1994 in Aachen ) was a German engineer who, through her findings and inventions, laid the foundations in the fields of aeronautical engineering , structural design and mechanical engineering .

Life

Childhood and youth

Ilse Essers (née Kober) was born in Munich as the second of five children to the married couple Anna Kober (née Boeltz) and Theodor Kober . Already in her school days she showed a clear talent for mathematics and science . Through her father, who worked as an engineer for Graf Zeppelin on the development of his first airship , she came into contact with aviation and aviation technology during her childhood.

When she was nine years old, the family moved to Friedrichshafen , where her father founded Flugzeugbau Friedrichshafen GmbH in 1912 . At the age of 15, on the advice of her mother and with the prospect of sometimes being able to fly, she became a drawing apprentice in her father's design office. "For us Kober children, flying was the epitome of everything beautiful, everything worth striving for."

After completing her apprenticeship, she initially continued to work as a technician in aircraft construction in Friedrichshafen and was soon responsible for speed and climb performance measurements on test flights .

Study and diploma thesis

The end of the war in 1918 brought the end of orders for aircraft in Friedrichshafen aircraft construction. The planes, which were half-finished by then, were converted for passenger air traffic and sold abroad. In order to start studying, Ilse Essers took her Abitur at a private school in Stuttgart in 1919.

Your original intention of studying mechanical engineering with a specialization in aircraft construction could not be pursued further due to the aircraft construction ban imposed by the victorious powers . Instead, she began studying physics and mathematics at the University of Munich. When she didn't like the lectures there, she switched to the TH in Munich and studied technical physics there.

Lack of money during the inflation forced Ilse Essers to look for sources of income in October 1922. For this purpose, she had put her thoughts on the “web loading of bending beams” into writing. She submitted her transcript to her professor, with whom she had passed her pre- examination examination in strength theory with "very good" and was hoping for a position as an assistant. She received a rejection with the comment on her thoughts: “Oh, that's nonsense. Read my books, everything is in them. "

Then she started working in a bookstore. A short time later she found a job as a draftsman at Deutsche Werken in the design office. A little later, at the same time as her father, she applied to the “ Caspar-Werke ” in Travemünde, which was looking for technicians for its aircraft factory, and got the job. Her father became technical director, to which she was subordinate again. However, the plant went bankrupt a short time later.

In 1924 she applied as an aircraft designer at Theodore von Kármán's Institute in Aachen and got a job as an assistant at the Aerodynamic Institute. She explained her theory to her director about the web stresses on bending beams, which her former professor regarded as nonsense. The latter agreed with her statements and asked her to write down her thoughts as an essay so that he could have it published in the Zeitschrift für Flugtechnik und Motorluftschiffahrt (ZFM) and recognize it as a thesis. Her goal was to “write an essay that every engineer can understand. [...] I always followed this principle later. "

Together with Theodor Bienen, she designed the FVA-6 motorized aircraft for the Aachen Aviation Science Association .

In 1926, after being awarded her engineering degree, she moved to Berlin to work at the German Aviation Research Institute (DVL) as an assistant in the aerodynamics department. She discovered the balancing of masses on movable wing flaps and wing rudders to prevent fanned wing vibrations and received a doctorate from the TH Berlin in 1929, as the first woman in the mechanical engineering faculty there .

Time as a housewife

In the same year she married Ernst Essers, whom she had met during her time in Aachen. Her husband held various posts in the Reichswehr, later in the Wehrmacht, which took the family to Berlin, Wünsdorf, Stahnsdorf and back to Berlin for a few years. During these years four children (one son and three daughters) were born.

After the Second World War, the family moved back to Aachen, where her husband at the RWTH Aachen , the Institute of Automotive Engineering served as Managing Director and professor. The 68-year-old Ernst Essers died unexpectedly on September 5, 1969.

After Ilse Essers had completed her work on coupled vibrations on trucks , she concentrated on writing her three biographies about Max Valier , Hermann Ganswindt and Prince Heinrich of Prussia .

On February 18, 1994 Ilse Essers died in Aachen at the age of 95 and was buried next to her husband in the Aachen forest cemetery.

Services

Doctoral thesis - "Investigation of wing vibrations in the wind tunnel"

An aerobatic pilot at show flight days informed the DVL ( German Research Institute for Aviation ) that wing vibrations occur at high airspeeds and that this leads to wing fractures.

In 1926, Ilse Essers became a technical assistant to the two mathematicians at the DVL, who had found a mathematical formula for the phenomenon of wing vibrations and were now in the process of measuring the natural vibration numbers of wings (wings) at a test station. The task of the two was to calculate the airspeed at which wing vibrations and thus wing breakage would occur. Ilse Essers had the task of carrying out experiments on small model wings in the wind tunnel. At that time, such attempts were recorded with cinema machines (a type of film camera that ejects a sequence of individual images). But since this was too time-consuming for her, she built a simple vibration recorder that reproduced her measurements as lines on paper. In her experiments she found that the mathematical formula did not take into account the influence of the aileron and had to be expanded accordingly, which the two mathematicians succeeded in doing. In new experiments she now used model wings with ailerons .

The fanned vibrations of the model wings began at a wind speed of 28.2 m / s. For a long time, she had been thinking about "influencing the vibration behavior by trimming the center of gravity of the aileron in front of the rudder axis." Generation of the wind current) there were no fanned wing vibrations. Other, slightly modified experiments also confirmed that a change in the center of gravity of the aileron affects the resonance area.

When she presented the results of her attempts to prevent wing vibrations to the highest director of the DVL, he immediately recognized the relevance for aircraft construction. Since he also gave lectures on aircraft construction at the TH Berlin, he asked her to write an elaboration of her thoughts so that he could submit it as a doctoral thesis.

She also submitted her invention of mass balancing on movable rudder surfaces against fanned wing vibrations to a scientific competition of the Scientific Society for Aviation (WGL) on the subject of "Working on improving the strength of aircraft" and received prize money of 1200  RM (her monthly The salary at that time was 450 RM).

"The design of the bathroom in social housing"

Around the beginning of the Second World War, the Nazi government began to develop plans for large-scale social housing after the final victory. Ilse Essers was asked to advise on the social housing plan , as she had already had some ideas in the area of thermal insulation . When the question of whether a bathtub or just a shower cubicle should be installed in the bathroom, Hitler is said to have preferred the shower cubicle. Ilse Essers, on the other hand, as well as her pediatrician and all employees of the project who were parents, were of the opinion that a bathtub was needed for children. It was therefore decided to install a bathtub in the bathroom, as "the guide in this case was not an expert".

When asked which bathtub to put in, she declined the usual four-legged bathtubs because the floor underneath was too difficult to clean. Deep, walled-in bathtubs were also not considered because they were too far away, which caused back pain. Your idea was to provide a raised, walled-in bathtub with a cavity for the feet. In 1942 Ilse Essers wrote the essay The design of the bathroom in social housing .

"About coupled vibrations on trucks"

One of the court cases in which her husband was an appraiser concerned a truck whose trailer, overloaded with heavy concrete pipes, broke loose while driving and hit the oncoming traffic. The question now had to be clarified whether the construction of the truck frame with the attachment of the trailer coupling was faulty or whether the overload was to blame for the trailer tearing loose. In the first experiments, Ernst Essers found that unknown forces acted on the drawbar while driving. His assumption was that it was vibrations, and since Ilse Essers was a vibration researcher at the DVL, he asked her to solve the problem.

After various tests, she found that not only longitudinal vibrations and the effects of the engine pulling force cause the drawbar forces, but above all pitching vibrations that are influenced by the distribution of the load on the trailer. Based on these findings, she wrote the work on coupled vibrations on trucks in 1956 , which was published in the Zeitschrift für Flugwissenschaften .

Honors

In memory of Ilse Essers and her achievements, the Dr. Ilse Essers Prize was launched in 2004 by the Zeppelin Foundation . Since then, the prize has been awarded annually to the best female graduate from the Baden-Württemberg Cooperative State University in Ravensburg . According to her is Ilse Essers Street Am Oberwiesenfeld in Munich's Milbertshofen named.

Central plants

Max Valier

The astronomer Max Valier , who first recognized the importance of the elementary rocket theory for space travel from Hermann Oberth , took over the technical development of this theory. His hope was that space travel would solve cosmic riddles. He began building ground vehicles and the first airplanes with powder rocket propulsion. This was followed by recoil motors for jet aircraft with liquid fuel and later the space rocket. After building the first combustion chamber for liquid fuel, Max Valier died on May 17, 1930 at the age of 35 in an explosion in the test facility.

Ilse Essers met Max Valier after dropping out of her physics degree when she was working in a Munich bookstore. In the 1950s, newspapers began to report on the experiments and achievements of the just beginning space travel. However, since Max Valier had already died at this time and Ilse Essers did not want to let his importance for space travel be forgotten, she decided to write a biography about him with the title: Max Valier, A pioneer in space travel, 1895–1930 , which was published by VDI-Verlag in 1968 .

Hermann Ganswindt

Hermann Ganswindt , who was the first to design the recoil drive for space travel, planned a. a. Aircraft whose task it should be to transport a cosmic vehicle to the extreme of the earth's atmosphere.

In memory of Hermann Ganswindt and his inventions, Ilse Essers wrote a biography about him with the title: Hermann Ganswindt, pioneer of space travel with his world vehicle since 1881 , which was also published in 1977 by VDI-Verlag. About her intention to write this book she wrote: “How highly honored Ziolkowski is in Russia, whereas his contemporary Ganswindt is completely forgotten in Germany. That has to be different. "

Prince Heinrich with his wife Irene

Prince Heinrich of Prussia, admiral and aviator

Since Ilse Essers had been looking in vain for a biography of Prince Heinrich of Prussia for years after the death of Prince Heinrich of Prussia , she decided to do so in memory of him and to write down his life.

Ilse Essers met the prince several times in her life, since Prince Heinrich of Prussia was a. a. made the task of promoting aviation and gliding in Germany.

Technology in my life

In her book "Technology on my way of life - As a woman and engineer in the early days of aviation technology", Ilse Essers tells of encounters in her life with technology and the history of technology linked to her life.

Fonts

• Peter F. Selinger (Ed.): Technology in my life path: As a woman and engineer in the early days of aviation technology. Weishaupt, Graz 1988, ISBN 3-900310-44-0 ; second, expanded and revised edition, Weishaupt, Graz 2004, ISBN 978-3-7059-0201-5 .
• Hermann Ganswindt: pioneer of space travel with his world vehicle since 1881. VDI, Düsseldorf 1977, ISBN 3-18-150026-7 .
• Max Valier, A Pioneer of Space Travel, 1895–1930 . VDI, Düsseldorf 1968 / Max Valier. A pioneer in space travel, Athesia, Bozen 1980, ISBN 88-7014-138-1 .
• (with Ernst Essers, J. Klein): Drawbar forces on trucks . Institute for Automotive Engineering at the Technical University of Aachen / West German Publishing House, Cologne / Opladen 1957.
• Investigation of wing vibrations in the wind tunnel. Dissertation on obtaining the title of doctoral engineer at the Technical University of Berlin submitted on November 8, 1928 by Dipl.-Ing. Ilse Essers, approved January 16, 1929.

Web links

• Literature by and about Ilse Essers in the catalog of the German National Library .

Individual evidence

1. ↑ ^{a b c d e f g h i j} Technology in my life: As a woman and engineer in the early days of aviation technology. 1988.
2. ^ History of the Institute for Motor Vehicles Aachen, accessed on February 7, 2016.
3. ↑ Family ads . In: FAZ , September 9, 1969, p. 25
4. ↑ Dr. Ilse Essers Prize . ( Memento of the original from February 7, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. City of Friedrichshafen 
5. ↑ Abendzeitung-muenchen.de