Zeitschrift für Flugtechnik und Motorluftschiffahrt (ZFM)
(Journal of Aviation Engineering and Motorized-Airship Aeronautics)
Click here for free access to Volume V (1914) (Warning: large file--ca. 85 MB)
ZFM was published from 1910 until at least 1933. (I suspect that it ceased publication as the result of the Gleichschaltung.) Initially, from 1910-1912, it was the official publication of the Verein Deutscher Flugtechniker [Association of German Aviation Engineers] (later Reichsflugverein). Thereafter, until 1933, ZFM was an official publication of the Wissenschaftliche Gesellschaft für Flugtechnik [Scientific Society for Flight Technology], which later, in 1914, transformed into the Wissenschaftliche Gesellschaft für Luftfahrt (WGL) [Scientific Society for Aeronautics]--today's Deutsche Gesellschaft für Luft- und Raumforschung (DGLR) [German Society for Aeronautics and Astronautics].
The Otto-Lilienthal-Museum in Anklam, located in the northeast corner of Germany, owns the whole set of ZFM--except for Volume V. In order to fill the gap for the Museum and individuals researching the early history of aviation, I have created an electronic version of the missing volume, using the copy owned by the University of Wisconsin-Madison Library.
(1) Pages containing text and drawings were scanned in "text mode." Pages containing photos were scanned in "gray-scale mode." While scanning in "text mode" resulted in sharper letters, scanning in "gray-scale" mode provided superior quality for the photos. In either case, pages were initially saved as TIFF files.
(2) The scanned images of the 29 photos on Tafel IV (a large fold-out sheet) in Heft 13 fall short in quality. Due to its large size and some damage (some tears along the creases), the fold-out sheet could not be manipulated sufficiently to reproduce the fairly good quality of the photos.
(3) The digitized volume is presented in text-readable PDF format. The text layer underneath the visual page images, which was created with the optical character recognition (OCR) software included in Adobe 9.0 Pro, serves three functions: It makes the text searchable; it enables readers to transfer text through copying and pasting; and it allows individuals who use screen-reading technology (such as blind people) to have access to the text.
Limitations: Text created through an OCR process is far from perfect; inevitably, some errors occur. In particular, text in Fraktur or unusual format (such as the journal title at the beginning of each issue) is likely to come out garbled. Mathematical formulas were not converted into a readable format (such as MathML). I also did not have the time to correct text errors manually. Nonetheless, I would estimate that roughly 95% of the searches will accurately find the matching words in the text. Screen-reader users should be able to get at least the jist of the text. Sighted users will see page images that are essentially identical to the original.
Note (4/7/2010; updated 10/28/2013): The 1910-1933 volumes of ZFM (Vol. 1-24) are now also commercially available in digitized format through Aviaebooks. They now appear to be text-readable (and thus searchable). Aviaebooks also offers numerous other works on German aviation between 1909 and 1944 (books and periodicals, including Flugsport--all in German) in PDF format. For most of these, the full text can be searched.
Note (12/6/2010): Good news: Volumes 1-13 (1910-1922) are now freely available online at the Hathi Trust Digital Library. These volumes are easy to navigate and searchable; the OCRed text is available. Unfortunately, the fold-out tables have not been scanned in. E.g., in Vol. 5 (1914), Table V (between pages 142 and 143) and Table IV (between pages 202 and 203) are missing. It appears that the high-speed scanning, done by Google as part of the Google Books Library Project, did not provide for the special treatment that the digitization of these oversized tables requires. Also, I found that the quality of the printed pages tends to be inferior to that of my own scans. While the full-text of Volumes 14/15 (1923/24) through 24 (1933) are currently not available on the Hathi Trust Digital Library site, it can be searched there.
Note (10/28/2013). Near the completion of this project in February 2009 (which--with all the new learning involved--took me some 25 hours), I found out that the 1910-1924 volumes of ZFM had become commercially available in digitized format through Avio E-Books. This appears to be no longer the case. Avio E-Books now specializes in historical documentation related to Italian aviation.
Visitors to this site may also enjoy the free archive to the back issues of Flight Magazine at Flightglobal/Archive.
Created, as a public service to the Otto-Lilienthal-Museum and the world at large, by:
Axel Schmetzke, Ph.D.
University of Wisconsin-Stevens Point
Stevens Point, WI 54481
Created February 19, 2009; last updated: Monday October 28, 2013