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tokens: negligibly, which suggests that for those cases, the lengthening of the spiral arms resulting from stripping can also give an appearance of unwinding without actually affecting the pitch angles. Schulz Struck ( 2001 ) noted possible winding of the inner spiral arms due to compression and ‘annealing’ of the disc in addition to unwinding of the outer regions of their face-on stripped galaxies. With the given sample, we do not have sufficient evidence to investigate this; however, with a larger sample of galaxies the effect of RPS on the more central spiral arms could be tested. The unwinding tails were found to be comprised of only the youngest stellar populations, in many cases only stars 20 Myr, when analysed with the sinopsis spectrophotometric fitting code. These have likely formed in situ , confirming that the unwinding effect only occurs in the gas component of the galaxy. Moreover, the age gradients observed in some unwinding arms possible capture the process in action, revealing a trail of progressively younger stars left by the opening arms of stripped material. Simulations were carried out of RPS interactions in different inclinations with respect to the ICM wind to investigate how the unwinding effect can arise and to compare the resulting morphology with observed features in the MUSE sample. The resulting snapshots were analysed throughout the stripping process, and used to produce ‘observations’ from different viewing angles to compare with the observed sample of galaxies. The two main effects that can, individually and in combination, give rise to an unwinding pattern are as follows: In edge-on wind interaction cases, the differential ram pressure in the leading and trailing edges of the disc causes a build-up of material in the leading edge. The tail becomes asymmetric and the slowed rotation of the gas causes the pitch angle to increase. In face-on wind interactions, the gas from the outer spiral arms is stripped and withdrawn from the potential well of the galaxy disc, causing it to move to higher orbits and increase the pitch angle in all directions from the disc. In most cases, a combination of these two effects will occur as a galaxy is stripped at angles between face-on and edge-on with respect to the ICM wind. Cases in which the galaxy is moving mostly edge-on to the wind appear to be more asymmetric and have tails that are further collimated to one side of the disc, while cases closer to face-on such as JO201 and JO85 show gas extending in a much wider range of directions from the disc. Furthermore, the simulations, combined with the phase-space positions of our galaxies and the sinopsis stellar population analysis, as well as similar effects found in the literature (Steinhauser et al. 2016 ; Roediger et al. 2014 ), all point towards the idea that the unwinding effect occurs only for galaxies undergoing first infall on radial plunging orbits, and appears to be a short-lived phase during stripping, containing stars