During NASA's MISSE-14 mission in 2021, a series of four samples that are candidates for use as solar or drag sails were analyzed for degradation under LEO conditions. The materials were placed on an outer ISS payload site in ram direction and exposed to the space environment for 0.36 years with an ATOX fluence of 2.54⋅1020 AO/cm².

One of the four sample slots was occupied with an uncoated FEP thin film sample and three others with coated FEP thin films. The coating consisted of a combination of aluminum and silicon oxide with aluminum as the outer layer. One of the coated samples was provided with a fold line and another sample consisted of several layers of coated FEP with cut-outs. The samples were measured before the flight, the mass and thermo-optical parameters were determined and microscope images were taken. During the mission, images of the samples were regularly taken in flight. Comparative measurements were carried out after the flight.

The paper presents a comparison of these measurements before and after flight and with laboratory experiments.