Dayglo in the 1950s
I think dayglo was around in the (late) 1950s. I saw a couple of Geminis (G-AKGC and KHH) and an Auster Autocrat (G-AJRN) at Tollerton with dayglo markings in October 1959. There was another Auster, an Aiglet Trainer G-APVG, at Rearsby, also in October 1959.
Several aircraft had dayglo in 1960, such as the Argosies G-APRL and M.
Laurence