M. Nakadate, S. Maekawa, K. Shibasaki, T. Kurose, T. Kitada, S. Segawa

A lighter version of envelope material has been developed based on a prior version developed at JAXA back in 2000. The prior version, which utilized Zylon® (PBO fiber from Toyobo) as its core fabric had a high tensile strength in weft direction of 1,310 N/cm and a low area density of 203 g/cm² . The material is excellent for a commercial use Stratospheric Platform (SPF) or high altitude airship as large as 250 m in length, however, is over-specification for a 150 m long technology demonstrator that might be developed prior to the commercial use vehicle. The make-up of the yarn and coating of the adhesive layer that could affect strength were taken into account in developing the material. The thinnest Zylon yarn available commercial off-theshelf was selected to make the core fabric as thin and light as possible and woven into a fabric fine and smooth enough to make thin and uniform coating of polyurethane layers possible. Thus developed material realized a tensile strength in weft direction of 993 N/cm, an area density of 157 g/cm² , and tested for several environmental conditions confirming its durability to environment. The thinner adhesive layer of the material made the reinforcement of the opening by bonding doublers more difficult than the prior version material. Reinforcing methods in terms of the materials, shapes of doublers and directions of the yarn were investigated. Evaluation tests confirmed that a double V shaped doubler (an inverted Von a V) was effective in recovering the strength. Tear propagation characteristics were also investigated by a biaxial tensile and a cut slit tear tests. It was confirmed that Thieles empirical formula in terms of tear propagation stress versus slit length is applicable to the developed material.

7th International Airship Convention 2008, Friedrichshafen

Conference Paper

englisch

21,0 x 29,7 cm, 9 Seiten

DGLR-Bericht, 2008, 2008-03, 7th International Airship Convention 2008 - Proceedings; S.1-9; 2008; Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V., Bonn

NA

in getr. Zählung;

materials, airship

Bestellbar

2008