Colored "ultralights"? Experts from CTU UCEEB give it the green light

News, 24/07/2018

Ultralight, or ultralight aircraft, is characterized primarily by the fact that it is designed for only two people, and the vast majority of these machines are produced in white. However, more and more customers of these planes want their color design, but technically it is not so easy to do.

The white color is mainly due to safety, when the effort is not to put a temperature burden on the "ultralight" construction. Thermal overload of the structure can be particularly dangerous when waiting for take-off in clear, sunny, windless weather. During its own flight and taxiing, it is sufficiently cooled by the flowing air.

However, the color design of these aircraft requires the designers to have maximum knowledge of the temperatures reached on the structure depending on the color. Therefore, as part of the analysis "Measurement of temperature load and emissivity of composite sandwich structures exposed to solar radiation depending on surface color treatments", we exposed several color variants of the structures to solar radiation in a solar simulator. We thus monitored the rate of heating of surface structures and their maximum temperature.

Our work continued by exposing the fuselage of an ultraligt with one wing to artificial sunlight in a solar simulator and placing temperature sensors at critical points of the structure. Subsequently, we again monitored the rise in temperatures after exposure to sunlight in individual locations.

During our research, we mainly observed the hull of the white ultralight. After correlating the result we obtained from previous research on color panels, it is now possible to evaluate the maximum temperatures for other colors as well. Thanks to this, we can adapt the production technology of ultralights so that they can withstand higher temperatures in a non-white design.